For Clinicians | Food Poisoning, Stomach Flu, or H. Pylori

Do You Actually Need Antibiotics?

By Dr. Jamie Wilkey, PharmD — Director of Clinical Strategy, Jase
Medically reviewed by Kristen Carpenter, PA-C — Clinical Advisory Board Member

Three patients, same complaint. One had a rough day after a backyard barbecue and is already turning the corner. One picked up whatever’s going around at daycare and brought it home to the whole family. One has lived with vague stomach discomfort for years. Ask any of the three if they have “a stomach infection” and they’d probably all say yes.

Only one of them actually does, in the literal sense. And not commonly tested for.

Food poisoning and the stomach flu get lumped in with real stomach infections constantly. Food poisoning and norovirus are usually done doing their damage by the time a patient’s in front of you, so there’s nothing left for an antibiotic to fix. There’s one specific presentation where reaching for antibiotics anyway doesn’t just fail to help, it can actively hurt the patient. And H. pylori sits underneath all of it: a real bacterial infection that can live in the stomach for years without a single symptom, then show up as heartburn nobody connects to the actual cause, and it’s the one of these three that almost always needs a real antibiotic course once someone thinks to look for it.

Getting this right changes what happens at the pharmacy counter and in urgent care. Here’s where the actual lines are for these top 3 ‘stomach bug’ presentations.

Do You Need Antibiotics for Food Poisoning or the Stomach Flu?

Almost never.
The reason is different for each.

Norovirus, the actual “stomach flu,” is viral. There’s no antibiotic target. Fluids and time are the entire treatment, and most people are through the worst of it in one to three days.

Food poisoning is where people expect a prescription and usually don’t need one. Most cases, Salmonella, Campylobacter, the toxin-producing bugs from undercooked meat or food left out too long, are self-limited in a healthy adult. IDSA’s own 2017 guidelines back this up directly: for uncomplicated Salmonella and Campylobacter in immunocompetent patients, the recommendation is supportive care, not antimicrobial therapy.¹ Antibiotics don’t reliably shorten the illness in these cases, and for Salmonella specifically, treating an otherwise uncomplicated infection can prolong how long someone keeps shedding the bacteria afterward.

There is only one big exception and that’s important for you to know. 

Bloody Diarrhea and Fever: Why Reaching for Antibiotics Can Backfire

This is the one every instinct in the room gets wrong, patient and clinician alike. Bloody diarrhea with fever looks like exactly the presentation that needs an antibiotic fast. It’s also the presentation where giving one, before you know what you’re treating, can make things worse.

The organism to worry about is Shiga toxin-producing E. coli, STEC, the kind behind most O157:H7 outbreaks. Killing the bacteria with an antibiotic can cause it to release more Shiga toxin as it dies, and that toxin is what drives hemolytic uremic syndrome, the kidney injury that’s the real danger here, especially in kids. CDC is direct about this: clinicians treating a patient whose presentation suggests STEC should know that giving an antimicrobial may raise the risk of HUS rather than lower it.² IDSA’s own guidelines back this with a strong recommendation: empiric antibiotics for bloody diarrhea, given before results are back, are not recommended in immunocompetent children or adults.³ For STEC confirmed to produce Shiga toxin 2, or when the toxin type isn’t yet known, IDSA goes further and says antimicrobial therapy should be avoided outright.⁴

The same logic applies to anti-diarrheal medications like loperamide. Slowing the gut down means the toxin sits in contact with the colon longer, and that’s also linked to higher HUS risk. The instinct to reach for Imodium while waiting on results is worth stopping while you’re at it.

This isn’t a blanket rule against ever treating bacterial diarrhea, and the mechanism explains why switching drugs isn’t a clever workaround: fluoroquinolones and trimethoprim-sulfamethoxazole are both potent triggers of the same bacterial stress response that ramps up Shiga toxin production. The largest look at real-world outcomes hasn’t found any antibiotic class that’s actually safer than the others. The safe default while you’re waiting on a stool culture and Shiga toxin testing stays the same: don’t treat empirically, and don’t reach for anti-motility agents, until you know what you’re dealing with.

1. Pylori: The Infection That Can Sit for Years Before Anyone Tests for It

This is the one that doesn’t announce itself. H. pylori can live in the stomach lining for years without a single symptom, then surface as heartburn, bloating, or vague upper-abdominal discomfort that gets blamed on stress, coffee, diet, or just getting older. By the time someone brings it up, they’ve often been living with it for a decade.

It won’t show up on a routine stool culture. Culture works by growing an organism, and H. pylori isn’t detected that way.⁵ Finding it takes a test built for it specifically: a urea breath test, which picks up the byproduct of the bacteria’s own urease enzyme, or a stool antigen test, which looks for H. pylori antigen directly. Either has to be ordered by name; neither is part of a standard workup.

The stakes here go past symptom relief. WHO’s cancer research arm classified H. pylori as a human carcinogen back in 1994, and the evidence has only held up since: it’s a major driver of non-cardia gastric adenocarcinoma, and nearly every patient with gastric MALT lymphoma tests positive for it.⁶ That’s the actual argument for testing someone whose “just stress” stomach discomfort has gone on for years, not just comfort, an infection tied to cancer risk that’s fully treatable once it’s found.

And when it’s confirmed, treatment isn’t a guess. Fourteen days now beats the older 7 to 10 day courses, eradication rates run meaningfully higher.⁷ Which drugs matter too: clarithromycin-based triple therapy only holds up where local resistance is low and the patient hasn’t had a macrolide recently, and bismuth-based quadruple therapy is the safer default when resistance status is unknown.⁸ This is a real regimen decision, not a reflexive prescription.

Quick Reference: Which One, Which Answer

Norovirus (viral “stomach flu”): No test needed in typical cases. No antibiotics, there’s no target. Fluids and time, usually resolved in 1 to 3 days.

Uncomplicated food poisoning (Salmonella, Campylobacter, toxin-mediated): Stool culture only if severe, prolonged, or high-risk. Antibiotics not recommended for uncomplicated cases in immunocompetent patients. Supportive care is the treatment.

Bloody diarrhea with fever (possible STEC): Stool culture plus Shiga toxin testing, ordered specifically, before treating. Avoid empiric antibiotics and avoid anti-motility agents like loperamide until results are back. Avoid antimicrobials outright if Shiga toxin 2 is confirmed or the toxin type is unknown.

1. pylori: Urea breath test or stool antigen test, ordered by name, not caught by routine stool culture. When confirmed, a real 14-day antibiotic course, bismuth quadruple therapy if resistance status is unknown, clarithromycin triple therapy only where local resistance is low.

What to Tell Your Patient

Most stomach bugs, the kind that hit hard and fast after a bad meal or a bug going around, don’t need antibiotics at all. Fluids, rest, and a few days usually settle it.

One exception: if diarrhea turns bloody and comes with fever, that’s a reason to call rather than push for an antibiotic. In some cases, antibiotics can make it worse instead of better, and that’s not an intuitive thing for a patient to already know.

The other stomach conversation to bring up: years of stomach discomfort chalked up to stress, coffee, or getting older is worth a specific test, not a shrug or an Rx for omeprazole. If it turns out to be H. pylori, it’s treatable.

The Bottom Line

Three complaints, one label, three different right answers. Most stomach bugs, viral or bacterial, resolve on their own and never need an antibiotic. The one case where reaching for one anyway can genuinely hurt a patient is bloody diarrhea with fever: test for Shiga toxin before treating, and skip the anti-motility agents too until you know what you’re dealing with. And the condition patients have been living with for years without a name, chronic dyspepsia blamed on stress or diet, deserves a specific test rather than another round of empiric PPI. If it’s H. pylori, a real 14-day course clears it.

Getting the label right is the whole job here. Getting it wrong either denies someone a cure they’ve needed for a decade, or pushes a treatment that makes a dangerous case worse.

Sources

1. IDSA, 2017 Clinical Practice Guidelines for the Diagnosis and Management of Infectious Diarrhea: for uncomplicated Salmonella and Campylobacter infection in immunocompetent patients, the recommendation is supportive care rather than antimicrobial therapy, and treating uncomplicated Salmonella can prolong the carriage state: https://pmc.ncbi.nlm.nih.gov/articles/PMC5848254/
2. CDC, Information for Clinicians: E. coli Infection: administering antimicrobial agents to a patient whose presentation suggests STEC may increase the risk of hemolytic uremic syndrome; anti-motility agents in STEC infection may increase the risk of toxic megacolon, HUS, and neurologic complications: https://www.cdc.gov/ecoli/hcp/guidance/index.html
3. IDSA, 2017 Clinical Practice Guidelines for the Diagnosis and Management of Infectious Diarrhea, Recommendation 30: empiric antimicrobial therapy for bloody diarrhea while awaiting diagnostic results is not recommended in immunocompetent children and adults (strong recommendation, low-quality evidence): https://pmc.ncbi.nlm.nih.gov/articles/PMC5848254/
4. IDSA, 2017 Clinical Practice Guidelines for the Diagnosis and Management of Infectious Diarrhea, Recommendation 35: antimicrobial therapy for infections attributed to STEC O157 and other STEC producing Shiga toxin 2, or when the toxin type is unknown, should be avoided (strong recommendation, moderate-quality evidence): https://pmc.ncbi.nlm.nih.gov/articles/PMC5848254/
5. Merck Manual, Helicobacter pylori Infection: bacterial culture has limited use for H. pylori because of the organism’s fastidious nature; urea breath testing and stool antigen testing are preferred for initial diagnosis: https://www.merckmanuals.com/professional/gastrointestinal-disorders/gastritis-and-peptic-ulcer-disease/helicobacter-pylori-infection
6. National Cancer Institute, H. Pylori and Cancer fact sheet: the World Health Organization’s International Agency for Research on Cancer classified H. pylori as a human carcinogen in 1994; it increases the risk of non-cardia gastric adenocarcinoma, and nearly all patients with gastric MALT lymphoma show signs of infection: https://www.cancer.gov/about-cancer/causes-prevention/risk/infectious-agents/h-pylori-fact-sheet
7. Cochrane, Ideal length of treatment for Helicobacter pylori eradication (Review CD008337): across 45 studies, extending PPI-based triple therapy from 7 to 14 days raised the eradication rate from 72.9% to 81.9% (NNT 11): https://www.cochrane.org/CD008337/UPPERGI_ideal-length-of-treatment-for-helicobacter-pylori-h.-pylori-eradication
8. American Academy of Family Physicians, H. pylori Infection: ACG Updates Treatment Recommendations: clarithromycin should be avoided where local resistance exceeds 15%; bismuth quadruple therapy should be strongly considered first-line where clarithromycin resistance is high or with any prior macrolide exposure; no regimen achieves a 100% cure rate: https://www.aafp.org/pubs/afp/issues/2018/0115/p135.html

For Clinicians | Cyclospora 101

Transmission, Diagnosis, and Treatment Behind the Current Case Surge

By Dr. Jamie Wilkey, PharmD — Director of Clinical Strategy, Jase
Medically reviewed by Kristen Carpenter, PA-C — Clinical Advisory Board Member

Your patients have probably already asked about this one. A parasite outbreak, spreading state by state, case counts climbing every week they check the news. Now almost every case of diarrhea is getting extra scrutiny and worry.

Here’s what most of the coverage isn’t quite getting right. CDC has been direct about it: there is no evidence of a single Cyclospora outbreak linking all the cases making headlines.¹ What’s actually happening is several separate clusters, each under its own traceback investigation, landing in the same news cycle because they’re all surfacing in the same few weeks of summer. A single traceable outbreak comes with a recall and an end date you can hand a worried patient. Several under-investigation clusters come with neither, plus a parasite that’s easy to miss on the test most of us recommend first.

So this isn’t another case-count update article. It’s the backstory: what Cyclospora cayetanensis actually is, why it shows up every summer, why the two things patients think are protecting them aren’t, why a clean stool workup doesn’t clear it, how to treat it, and what to tell the patient who’s allergic to the first-line drug. That’s how we want to help this week, whether you’re seeing the patient in the office or filling the prescription at the pharmacy counter.

What Cyclospora Actually Is, and Why It’s a Summer Problem

Cyclospora cayetanensis is a single-celled parasite, not a bacterium and not a virus, and that distinction is exactly why the stool tests built for bacterial pathogens keep missing it. It gets into the body the way most foodborne illnesses do: contaminated food or water, usually fresh produce that picked up the parasite in the field before it ever reached a grocery shelf.

That’s also why this tends to show up in the warmer months instead of everywhere at once. Documented outbreaks have clustered in spring and summer, tracking harvest windows for produce implicated before: cilantro, basil, raspberries, snow peas, bagged salad mixes.² The parasite needs warm, wet growing conditions to survive on a leaf or in irrigation water, which is most of why the season tracks the produce. CDC itself is upfront that the seasonal pattern isn’t fully understood and can vary year to year.

Symptoms start an average of a week after exposure, with a range from two days to two weeks or longer,³ which is plenty of time for most patients to have forgotten which salad or smoothie they’d even blame by the time they’re in front of you.

The traceback complaints you’ve probably heard about aren’t a competence problem. Contamination happens upstream, on the farm or in the wash water, long before the product reaches a shelf. By the time a cluster gets reported, the implicated produce is usually gone, and the oocyst itself is hard to detect on food even when investigators know exactly where to look. That’s most of why this season, like most Cyclospora seasons, is landing without a single, obvious recall notice to point patients to.

Now remember,  this isn’t Giardia. Even though the two get confused constantly and both cause watery diarrhea traced back to contaminated food or water. Giardia shows up on a routine stool antigen test or standard multiplex panel without any special request. Cyclospora doesn’t.

Does Washing Produce Protect Against Cyclospora?

No, and this is the myth worth correcting every single time it comes up. Washing produce under the tap, even scrubbing it, does not reliably remove Cyclospora oocysts.⁴ Standard chlorine-based sanitizers, the same ones that work fine against most bacteria on fresh produce, don’t reliably inactivate this oocyst either. The only thing that reliably kills it is heat: cooking, boiling, baking.

That’s worth really communicating to a worried patient, because the instinct is to blame their own kitchen habits. They didn’t wash carelessly. The oocyst gets onto produce in the field or in irrigation water, well before anyone in their house ever touched it, and no amount of rinsing at home was going to undo that. This is a supply chain and traceback problem, not a hygiene-compliance problem, and patients need to hear that distinction instead of walking away thinking they did something wrong.

What About Person-to-person Spread?

The second myth is about who else in the house is at risk. Direct person-to-person spread is unlikely, and the reason is mechanical: the oocysts shed in a bowel movement aren’t infectious yet. They need roughly one to two weeks outside the body to sporulate before they can infect anyone else.⁵ A parent with cyclosporiasis is not a transmission risk to their kids the way a parent with norovirus is. The exposure that mattered already happened, probably at a meal everyone ate together, which is why cases often cluster by household without any household member infecting another.

The Symptom Pattern That Gets Mistaken for Recovery

Watery diarrhea is the leading symptom, often profuse and explosive enough that patients bring it up before you even ask. Most also report cramping, nausea, low-grade fever, and a fatigue that feels disproportionate to the diarrhea itself. Anorexia and real weight loss show up often enough to ask about directly. Blood or mucus in the stool is less common, and when it shows up, it’s worth considering whether something else, on top of the Cyclospora, is also going on.

The detail that matters most clinically is the shape of the illness, not just the symptom list. Left untreated, cyclosporiasis can run for weeks to months,⁶ and it rarely runs in a straight line. Some patients get a single, self-limited stretch that resolves on its own. Many more get a waxing-and-waning course: a few days of feeling noticeably better, then a relapse that brings the diarrhea and fatigue right back. That pattern is exactly what makes this so easy to write off. A patient who feels better on day ten looks recovered. A patient who’s still cramping on day twenty-five gets told it’s probably just taking longer than usual, or that it’s turned into post-infectious IBS. Neither read is wrong often enough to catch, because the actual explanation, an active infection nobody tested for, isn’t on either differential.

Watch this more closely in infants, older adults, and immunocompromised patients, where the same illness runs harder: more dehydration, more real malnutrition risk, and a rare but real mortality risk in the most vulnerable of that group.⁶

Does a Stool Culture or Routine O&P Detect Cyclospora?

Short answer: not reliably. Don’t assume a standard panel catches it.

A routine ova and parasite exam uses wet-mount and trichrome stains that Cyclospora oocysts don’t take up well.⁷ The organism can be there and still go unseen, or show up faint enough to write off as debris. Finding it reliably takes a stain built for this organism specifically, a modified acid-fast stain or a safranin stain, and neither is standard on a routine O&P order. It has to be requested by name.

Multiplex PCR panels solve part of the problem, but only if Cyclospora is actually on the panel. Coverage varies by manufacturer, and plenty of the GI panels in wide clinical use don’t include it as a target at all.⁷ Before trusting a negative PCR, confirm Cyclospora was actually one of the organisms that panel was built to detect.

Then there’s shedding. Patients don’t shed oocysts in every bowel movement, so a single specimen, even with the right stain or the right panel, can come back falsely negative.⁸ Microscopy-based testing typically needs specimens collected on separate days to be reliable; a targeted PCR is more forgiving and can often catch it from one well-timed sample. A patient with three weeks of symptoms and one negative stool study hasn’t been ruled out. They’ve had one attempt at the wrong test, or one attempt at the right test on an unlucky day.

Quick Reference: Ordering for Cyclospora

• Test to order: modified acid-fast stain or safranin stain on microscopy, or a GI multiplex PCR panel confirmed to include Cyclospora as a named target.
• Why routine testing misses it: standard O&P wet-mount and trichrome stains don’t reliably visualize the organism, and not every PCR panel tests for it.
• If microscopy is negative: don’t stop at one sample. CDC recommends three or more specimens spaced 2 to 3 days apart before ruling it out.
• If PCR is negative: confirm Cyclospora was actually on that panel. If it was, one well-timed sample is usually sufficient.

Cyclosporiasis Treatment: TMP-SMX Dosing, and What to Do for the Sulfa-Allergic Patient

Trimethoprim-sulfamethoxazole is first-line, and for most adults it works well. The standard course is one double-strength tablet (TMP 160mg/SMX 800mg) by mouth, twice a day, for seven to ten days.⁹ Most patients start feeling meaningfully better within the first few days. Patients with HIV may need a longer course to fully clear it.

The sulfa-allergic patient is the real open problem in this article, and it deserves a straight answer instead of a reassuring one. CDC’s own language here is blunter than most clinicians expect: no highly effective alternative to TMP-SMX has been identified.¹⁰ Ciprofloxacin gets reached for first, but the evidence behind it is thin. One small study in HIV-positive patients in Haiti showed modest activity, and against that sits a lot of anecdotal clinical experience suggesting it just doesn’t work well in immunocompetent patients. Nitazoxanide gets prescribed too, and it’s also less effective than TMP-SMX where it’s actually been studied.

So what do you actually do? For a patient who’s truly sulfa-allergic, CDC lists three real paths, not two backup drugs to cycle through: observation with symptomatic treatment while the infection runs its course, a trial of one of the less-proven antibiotics with the patient told upfront that it may not work, or referral for TMP-SMX desensitization. Desensitization doesn’t come up enough in conversations about this parasite, and it’s worth having in your back pocket for the patient who needs a real cure and can’t take the drug that reliably delivers one.

What to Tell Your Patient

First, washing all produce helps in general, just not with this one specific parasite. It’s not their fault, and it’s not a reason to scrub harder next time.

Second, they’re not about to infect the rest of the household. The exposure already happened, probably at a shared meal, and there’s nothing contagious about sitting next to them at dinner tonight.

If a stomach bug has dragged on more than a week or two, especially with cramping, fatigue, or weight loss that won’t quit, that’s not “give it more time” anymore. That’s “ask whether anyone’s tested specifically for a parasite.”

The Bottom Line

Cyclospora cayetanensis is having a real season, and the headlines are outrunning what’s actually confirmed about it. That part will sort itself out as the traceback investigations close.

What won’t sort itself out on its own is the diagnostic habit. A routine O&P or an untargeted GI panel can come back clean and still miss this. If a patient has weeks of watery diarrhea, cramping, and fatigue that won’t resolve, name the test: modified acid-fast stain, or a PCR panel confirmed to include Cyclospora. Treat with TMP-SMX first. And if the patient’s allergic to it, know going in that the backup options are weak, so observation, a documented trial of a less-proven drug, or desensitization done through an allergist, and only for patients without a life-threatening allergy, are the real conversation…. not a quick swap to ciprofloxacin and moving on.

That’s the difference between a case that resolves in a week and one that drags on for a month before anyone catches it.

Sources

1. CDC statement that there is no evidence of a single Cyclospora outbreak linking current cases, several clusters remain under separate traceback investigation, as reported by CBS News Texas, July 2026: https://www.cbsnews.com/texas/news/cyclosporiasis-texas-diarrhea-2026-cdc/
2. CDC, Clinical Overview of Cyclosporiasis: seasonality varies by setting and is not fully understood: https://www.cdc.gov/cyclosporiasis/hcp/clinical-overview/index.html. CDC, U.S. Foodborne Outbreaks of Cyclosporiasis, 2000–2017: past outbreaks have been linked to fresh produce including cilantro, basil, raspberries, snow peas, and bagged salad mixes: https://stacks.cdc.gov/view/cdc/118740 
3. CDC, Clinical Overview of Cyclosporiasis: incubation period averages one week, ranging from 2 days to 2 weeks or more: https://www.cdc.gov/cyclosporiasis/hcp/clinical-overview/index.html
4. FDA, Cyclosporiasis and Fresh Produce: standard washing and chlorine-based sanitizing do not reliably remove or kill Cyclospora oocysts; only cooking reliably inactivates them: https://www.fda.gov/food/foodborne-pathogens/cyclosporiasis-and-fresh-produce
5. CDC, About Cyclosporiasis: oocysts require roughly 1 to 2 weeks outside the body to become infectious, so direct person-to-person transmission is unlikely: https://www.cdc.gov/cyclosporiasis/about/index.html
6. Mathison and Pritt, “Cyclosporiasis—Updates on Clinical Presentation, Pathology, Clinical Diagnosis, and Treatment,” Microorganisms (2021): untreated illness may last weeks to months with a relapsing-remitting course, and runs more severe in infants, older adults, and immunocompromised patients: https://pmc.ncbi.nlm.nih.gov/articles/PMC8471761/ 
7. CDC, DPDx Cyclosporiasis: routine wet-mount, trichrome, and Giemsa stains are not adequate for reliable detection; modified acid-fast or safranin stains are required, and not all commercial multiplex PCR panels include Cyclospora as a target: https://www.cdc.gov/dpdx/cyclosporiasis/index.html
8. CDC, DPDx Cyclosporiasis: oocysts are shed intermittently and in low numbers, so a single negative specimen does not rule out infection; three or more specimens at 2- to 3-day intervals may be required: https://www.cdc.gov/dpdx/cyclosporiasis/index.html
9. CDC, Clinical Care of Cyclosporiasis: TMP-SMX dosing of one double-strength tablet twice daily for 7 to 10 days in adults, with longer courses considered for patients with HIV: https://www.cdc.gov/cyclosporiasis/hcp/clinical-care/index.html
10. CDC, Clinical Care of Cyclosporiasis: no highly effective alternative to TMP-SMX has been identified; options for sulfa-allergic patients include observation with symptomatic care, an alternative antibiotic supported by limited data, or TMP-SMX desensitization for selected, allergist-evaluated patients without a life-threatening allergy: https://www.cdc.gov/cyclosporiasis/hcp/clinical-care/index.html. The ciprofloxacin data point traces to a 2000 randomized trial in 42 HIV-infected patients in Port-au-Prince, Haiti: TMP-SMX outperformed ciprofloxacin, 95% versus 70% negative stool tests by day 7 (Annals of Internal Medicine, 2000): https://pubmed.ncbi.nlm.nih.gov/10836915/. Nitazoxanide as a sulfa-allergy alternative, with the caveat that treatment failure may occur, is per Mathison and Pritt (Source 6).

For Clinicians | The Tooth Infection at Your Counter:

What to Do When the Dentist Is Days Away

By Dr. Jamie Wilkey, PharmD — Director of Clinical Strategy, Jase
Medically reviewed by Kristen Carpenter, PA-C — Clinical Advisory Board Member

Almost none of us trained to manage a tooth. I know I sure didn’t as a pharmacist. Yet the tooth finds us anyway. It’s the patient at the pharmacy counter asking which antibiotic works for a throbbing molar (as if they had access to the antibiotic even if I told them). It’s the primary care visit that turns out to be a three-day toothache. It’s the roughly two million dental visits to US emergency departments every year, most of which end the same way: an antibiotic, something for the pain, and a referral to a dentist the patient still has to go find.

So this is the dental guidance most of us never got in our professional schooling. Not how to do the dentistry, but what to actually say and prescribe in the gap: which toothaches are emergencies and which aren’t, what antibiotics genuinely do for an infected tooth, and what the right move is when the patient in front of you can’t get to a dentist for days. It turns out the clinical answer runs almost opposite to what the search results promise, and it starts with a piece of anatomy. Let’s jump into that, shall we?

Why can’t antibiotics just fix the tooth?

By the time a tooth is infected enough to hurt like that, the pulp inside it is usually dead. Dead tissue has no blood supply. And no blood supply means no delivery route: the antibiotic circulating through the patient’s bloodstream physically cannot reach the bacteria walled up inside that tooth. You can run a full course and the source sits there untouched.

So the thing that actually cures a tooth infection isn’t a drug at all. It’s source control: draining the abscess, opening the tooth, a root canal, or pulling it. Mechanical, not pharmacologic. The dentist isn’t the backup plan when antibiotics fail; the dentist is the treatment. Antibiotics do one useful job in the meantime: they hold back a spreading infection and buy time. They are the bridge, not the destination.

This is exactly why the American Dental Association, in its 2019 guideline, tells dentists not to prescribe antibiotics for most toothaches. Not to conserve them, though that matters too, but because for a garden-variety symptomatic tooth they mostly don’t work as the patient imagines. The search results promising an antibiotic that will “save your life” from a tooth infection have the mechanism backwards. The antibiotic buys the time. The dental chair saves the tooth.

So when ARE antibiotics indicated?

The 2019 ADA guideline draws the line at the patient’s body, not the tooth. For a healthy adult with a symptomatic tooth and no systemic signs, the recommendation is no antibiotic. Refer for dental treatment, and manage the pain in the meantime. And the pain tool that actually works here is not an opioid: 400 to 600 mg of ibuprofen combined with 1000 mg of acetaminophen outperforms both, and outperforms most opioid combinations, for acute dental pain. Worth having at ready a patient in dental agony begs to know from you what to take.

Antibiotics enter when the infection stops being local. Two triggers: systemic involvement (fever, malaise, the look of someone whose infection has left the tooth), or the access situation where definitive dental care simply isn’t reachable in a useful timeframe. Hang on that second one; it’s the whole back half of this article.

The signs that mean escalate now, not tomorrow are: fever, swelling that’s spreading toward the eye or down into the neck, and any trouble swallowing or breathing. That last cluster is how a tooth becomes Ludwig’s angina, a deep neck-space infection that can close off an airway. It’s rare, and it still kills roughly 8% of the people who develop it. Most toothaches are nowhere near this. But the patient can’t tell the difference on their own, and that triage line is the single most useful thing we hand them.

Dentistry has a stewardship problem, and you’re standing in it

Dentists write roughly one in ten of all outpatient antibiotic prescriptions in this country, about 25 million courses a year. And after the 2019 guideline told them to prescribe less, the volume barely moved. Antibiotics still show up in 12 to 28% of visits for the exact acute infections that mostly shouldn’t get them, from irreversible pulpitis to apical abscess, and when they are prescribed the course runs eight days or longer nearly half the time. On the prophylaxis side, the “premedicate before the cleaning” scripts, more than 80% don’t match current guidance at all.

The single best stewardship tool for a tooth is the procedure: drain it, open it, pull it, and the antibiotic becomes unnecessary. Non-dentists can’t do the procedure. No way! Which means when the tooth shows up at the pharmacy counter or the urgent care, the stewardship move isn’t a better antibiotic choice. It’s the triage from the last section: is this local or systemic, and is the patient actually on a path to a dentist, or are we about to write a course that becomes the treatment plan by default?

That default is the trap. An antibiotic handed over without a dental appointment behind it doesn’t buy time toward a fix; it just postpones the same infection, minus a few days of the drug’s usefulness against everything else the patient carries. The bacteria in the tooth recolonize the moment the course ends, because, again, the source was never touched. So the stewardship question at our counter is less “which drug” and more “what is this drug bridging to.” If the answer is nothing, the prescription isn’t stewardship. It’s a delay with side effects.

So what about when there’s no dentist to bridge to?

This is the second trigger from earlier, and it’s the one the guideline names but never develops. The ADA’s own language reserves antibiotics for systemic signs or for when definitive dental treatment is not available. That second clause is doing non-obvious work. It’s the guideline admitting that access, not just biology, decides whether a drug is appropriate.

And access fails in ordinary ways. A molar goes bad on day two of a cruise. A crown cracks on a Friday night heading into a holiday weekend. A patient is three hours from the nearest dentist taking new patients, or on an international trip where the local pharmacy stock is counterfeit or degraded. In every one of these, the bridge has somewhere to go, it’s just days out instead of hours. This is exactly where a course of antibiotics does the job we described: holding a spreading infection in check until the chair is reachable.

Notice this is the same logic as any standby antibiotic. Resistance is driven by how antibiotics are used, not by whether a patient keeps a course on a shelf. A well-chosen drug, matched to a condition the patient can actually recognize, held for the moment access disappears, is not the thing that breeds resistance. Misuse is. Advance provision has been standard wherever access is the binding constraint long before we came along: ships carry antibiotics for crew with no physician aboard, and expedition medicine sends them where evacuation is days away.

The boundary matters as much as the case. This is for the recognizable dental infection when a dentist is genuinely out of reach. It is not for the vague ache the patient could get seen for on Monday, and it is never a reason to skip the dentist once one is reachable. The drug buys the trip to the chair. It does not replace it.

The grey space, and the kit we built for it

Right now the tooth gets all-or-nothing care. Either the patient reaches a dentist while it still matters, or they’re left with a search bar and whatever’s in the cabinet. There’s no sanctioned middle: no clinician-built step that readies someone for the one dental problem they can actually recognize, before access fails. That gap is where we work, and we call the category by name on purpose: appropriate medical preparation. The right drug, a real indication, clear instructions, prescribed ahead of the moment access disappears.

The Jase dental kit is that idea made concrete. A licensed provider prescribes it before the trip or the storm: the antibiotic clinicians reach for in dental infections, a prescription anti-inflammatory for the pain, and a topical numbing gel for adults, with condition cards that spell out dosing and what each medication is for. It’s the office and the pharmacy, packed for the patient before the molar goes bad three time zones from home.

A note on the pain side, because it matters at the counter: the kit’s anti-inflammatory is celecoxib, a prescription NSAID, but the combination that actually tops the evidence for dental pain, ibuprofen plus acetaminophen, is over the counter and already sitting in most medicine cabinets. Point patients there first for the pain itself, no prescription needed. Celecoxib is the option for those who can’t take standard NSAIDs or want once-daily dosing.

We hold this to the same bar we’d hold any standby course. Right drug, chosen deliberately. A documented indication, not “antibiotics, just in case.” Dosing and duration set by the prescriber, never self-terminated when the pain eases. And clear direction back to a clinician. That’s the part we keep sharpening, and it’s the part that separates preparation from a leftover stash. The kit is the bridge. The dentist is still the cure.

The bottom line

Antibiotics don’t cure a tooth infection; a dentist does, because the source is walled off from the bloodstream. Most toothaches aren’t emergencies, and the triage line (fever, spreading swelling, trouble swallowing or breathing) is the most useful thing we hand a patient. At the counter, the real stewardship question isn’t which antibiotic, it’s what the antibiotic is bridging to. And when the answer is a dentist who’s genuinely days away, a well-chosen course prescribed ahead of time is preparation, not excess. For the patients you’d rather not manage in this grey space yourself, send them to us at Jase.com.

Sources

1. Lockhart PB, Tampi MP, Abt E, et al. Evidence-based clinical practice guideline on antibiotic use for the urgent management of pulpal- and periapical-related dental pain and intra-oral swelling. J Am Dent Assoc. 2019;150(11):906-921.e12. (Recommends against antibiotics for immunocompetent adults; reserves them for systemic involvement or when timely definitive dental treatment is unavailable; NSAID dosing of 400-600 mg ibuprofen plus 1000 mg acetaminophen.) https://pmc.ncbi.nlm.nih.gov/articles/PMC8270006/
2. American Dental Association. Antibiotics for Dental Pain and Swelling (public guideline summary). https://www.ada.org/resources/research/science/evidence-based-dental-research/antibiotics-for-dental-pain-and-swelling
3. Cackley AP, et al. Emergency Department Visits for Tooth Disorders: United States, 2020-2022. CDC NCHS Data Brief No. 531, June 2025. (An annual average of 1,944,000 ED visits for tooth disorders.) https://www.cdc.gov/nchs/products/databriefs/db531.htm
4. Huynh CVT, Gouin KA, Hicks LA, et al. Outpatient antibiotic prescribing by general dentists in the United States from 2018 through 2022. J Am Dent Assoc. 2025. (Dentists wrote 9.8%-12.1% of outpatient antibiotics; 25.17 million prescriptions in 2022; volume stable after the 2019 guideline.) https://pmc.ncbi.nlm.nih.gov/articles/PMC12058375/
5. Carlsen DB, et al. Concordance of Antibiotic Prescribing with the American Dental Association Acute Oral Infection Guidelines within Veterans Affairs Dentistry. Infect Control Hosp Epidemiol. 2021. (Antibiotics given in 12% of irreversible pulpitis, 17% of apical periodontitis, and 28% of acute apical abscess visits; prolonged courses of 8+ days in 42-49%.) https://pmc.ncbi.nlm.nih.gov/articles/PMC8410877/
6. Suda KJ, Calip GS, Zhou J, et al. Assessment of the Appropriateness of Antibiotic Prescriptions for Infection Prophylaxis Before Dental Procedures, 2011 to 2015. JAMA Netw Open. 2019. (80.9% of dental antibiotic prophylaxis prescriptions were unnecessary.) https://pmc.ncbi.nlm.nih.gov/articles/PMC6547109/
7. Cleveland Clinic. Ludwig’s Angina. (Deep neck-space infection, most often from lower molars; roughly 8% of those who develop it die.) https://my.clevelandclinic.org/health/diseases/23457-ludwigs-angina

For Clinicians | Bacterial vs Viral Infection

When Antibiotics Actually Help, and When to Wait

By Dr. Jamie Wilkey, PharmD — Director of Clinical Strategy, Jase
Medically reviewed by Kristen Carpenter, PA-C — Clinical Advisory Board Member

How do you know if an infection is bacterial or viral?

Every one of us has had this visit. A patient who feels awful, certain it’s bacterial, already asking for the antibiotic by name. And an exam that, if we’re being straight about it, could go either way.

Here’s the really hard part: signs alone often can’t separate bacteria from viral. Not reliably. And the labs don’t bail us out the way we’d like, either. CRP, procalcitonin, a white count, even all three together nudge the probability without handing over a clean, clear, simple verdict. Patients lean hard on yellow mucus, a single fever, the ‘it’s been five days’ clock. None of those reliably tell you a thing. They feel diagnostic but darn it, they aren’t. And they drive a whole lot of prescriptions that never had a real shot at helping.

So this isn’t going to be a bacterial-versus-viral checklist. You’ve already got one. What’s actually hard, and what actually changes outcomes, is the layer underneath: holding that uncertainty well in front of a patient who came in wanting a clean answer and a prescription.

So today we’re walking the three moves that live in this gray space. What genuinely raises suspicion. When waiting is the right call, and why the evidence backs it instead of treating it as a cop-out. And the narrow, specific place a standby antibiotic actually belongs. None of it skips the clinical judgment. All of it just makes that judgment easier to hold.

The real skill is holding the uncertainty

We were trained to find the answer. Name the bug, match the drug, move on. That reflex gets drilled in from our first courses of our advanced degrees. So when the answer won’t come, when the exam and the labs both just shrug at us, it feels like a failure of skill rather than a feature of the disease. It isn’t. Most everyday infections live in that gray, and the actual skill is staying steady inside it instead of forcing a resolution that the evidence won’t support.

And that brings us to the typical forced resolution. It’s the antibiotic prescription. We all know the pull: the patient expects it, the visit is already running long, and a script is the fastest way to send everyone home feeling like something happened that was worth their copay. Nobody sets out to over-prescribe. It’s just that “let’s treat it to be safe” is the path of least resistance, and patients have learned to expect it, which makes the next clinician’s “no” land like somebody’s holding out on them.

Holding the uncertainty well is the alternative, and it’s a real clinical act, not a soft one. It means saying out loud the thing we’d rather not: I can’t tell you for certain today whether this is bacterial, and here’s why that’s actually okay. It means giving the patient a plan for both branches instead of a pill for one. If this is viral, here’s the course it should run and the exact point where you come back. If it turns, here’s what we do then. That isn’t doing nothing. That’s doing the harder thing.

Everything that follows sits on that footing. The three moves aren’t a way around the uncertainty. They’re how you hold onto it without dropping it on the patient or papering over it with a drug.

What actually raises suspicion for a bacterial infection?

Let us start with the caveat that matters: almost everything here is probabilistic. These aren’t rule-in tests, they’re the findings that move the needle just enough to act, and they look different in every category. Here’s where the suspicion is actually earned in the infections we see most.

UTI: the symptom is the diagnosis. A positive dipstick is not a UTI. Bacteriuria without attributable symptoms (dysuria, urgency, frequency, suprapubic pain) is asymptomatic bacteriuria, and IDSA recommends against treating it in almost everyone outside pregnancy and patients headed for a urologic procedure.¹ This is the cleanest version of the whole article’s premise: a positive test is not an infection. The patient with real symptoms and a positive dip is a different person than the patient with a positive dip and nothing else, and only one of them has a UTI.

Skin and soft tissue: here you actually do get to trust your eyes, mostly. Cellulitis announces itself with spreading warmth, redness, and tenderness. The hard call usually isn’t “is it bacterial,” it’s “how sick is this person,” and that’s where the red flags matter more than the label:

• Pain out of proportion to what you’re seeing (think necrotizing, and move fast)
• Rapid progression you can track by the hour
• Systemic toxicity: fever, hypotension, a sustained tachycardia, two or more SIRS criteria

Those move a patient from “treat and recheck” to “this needs a higher level of care right now.” The flip side is just as useful: uncomplicated cellulitis should turn the corner within 24 to 48 hours of starting therapy.² If it doesn’t, the next question isn’t “stronger antibiotic,” it’s “wrong diagnosis, or something deeper.”

Strep throat: this is what Centor is for. Tonsillar exudate, tender anterior cervical nodes, absence of cough, a history of fever. Fewer than three of those and most patients need neither a swab nor a script.³ The reflex to test and treat every sore throat is exactly the low-value move the score exists to stop.

Respiratory (the big one): this is where suspicion should be hardest to earn, not easiest. Most acute sinusitis, and essentially all acute bronchitis, is viral.⁴ Antibiotics in sinusitis are for genuinely bacterial features or persistence past an observation window, not for the calendar and not for the color of what’s in the tissue. Bronchitis doesn’t get an antibiotic unless you’re actually worried about pneumonia. Cold, flu, COVID: never. This is the category that generates the most “I’m sure it’s bacterial” visits and the fewest infections that actually are.

The thread through all four: suspicion is local and specific, not a global sense that someone seems sick enough to deserve a drug. When the findings genuinely line up, you treat. When they don’t, you’ve got a second move that’s every bit as evidence-based as the first.

When is it safe to wait?

Now before you start to stress seeing this section title take a deep breath. This is the move that feels wrong until you look at the data, and then it feels obvious. Watchful waiting isn’t the absence of a plan. Done right, it is the plan, and it has a real evidence base under it.

The cleanest version is the back-up, or delayed, prescription: the patient leaves with a script in hand (or one you’ll send if needed), plus clear instructions to fill it only if they aren’t improving by a set point or they cross a specific line you’ve drawn. The Cochrane review on delayed prescribing for respiratory infections found it cut antibiotic use sharply versus prescribing immediately, with no increase in complications and patient satisfaction that holds up.⁵ The individual-patient-data meta-analysis landed in the same place: for most symptom outcomes, delayed performs about as well as immediate, and far better on the number that matters for stewardship, which is how many people actually swallow an antibiotic they never needed.⁶

What makes it work is the part we can’t skip: the return plan. Delayed prescribing is safe because the patient knows exactly what they’re watching for and exactly when to come back. Take that away and it’s just a slower prescription. And there’s a real caveat to sit with: at least one analysis tied delayed prescribing in upper-respiratory infection to a higher risk of hospital admission, a reminder that this is a tool for the borderline, self-limited case, not a blanket policy you run on everyone who walks in.⁷ The sicker the patient and the higher the stakes, the less this belongs.

Used in its lane, though, the back-up prescription is one of the most useful tools we have for the gray space. It tells the patient the truth: I don’t think you need this today, I could be wrong, and here’s how we’ll both know. It treats them as a partner in the uncertainty instead of resolving it on their behalf with a drug they probably don’t need.

And notice what it actually is, underneath. It’s a clinician deciding, ahead of time, that an antibiotic is warranted only if a specific condition is met, then putting the medication within reach for that exact moment. Hold that thought. It’s the whole idea behind the third move.

So what IS it for, down there? A short, specific list:

• Giardiasis
• Amebiasis (intestinal, and liver abscess), followed by an intraluminal agent
• C. diff, with the asterisk from a minute ago: not first-line anymore
• Intra-abdominal infection, where it’s always paired with a gram-negative agent, never flying solo

Notice what’s missing. Undifferentiated “food poisoning.” Routine traveler’s diarrhea, too. CDC’s Yellow Book puts azithromycin first-line and fluoroquinolones second for traveler’s diarrhea and metronidazole isn’t on that ladder at all. It’s reserved for Giardia, and even there it’s one option alongside tinidazole and nitazoxanide.⁸ It’s a specialist, not a generalist. Reach for it when you’ve got an anaerobe or a protozoan in your sights…not when a patient tells you their stomach is “off.”

And that narrowness, the very thing that makes it the wrong empiric pick for a vague gut complaint, is exactly why metronidazole can’t be the only gut drug in any kit worth building. Which is right where we’re headed next.

Where does a standby antibiotic actually fit?

So far, the gray space has had a clinician standing in it. Someone to examine, to decide, to be called back in 48 hours. Almost everything above assumes that person is reachable. Pull that assumption out, and the picture changes.

Think about the patient who is genuinely going to need an antibiotic and genuinely can’t get to anyone when the moment arrives. The recurrent-UTI patient with a documented workup and a clinician-set plan, who feels the exact symptoms she’s felt a dozen times, on a weekend, six hours from the nearest clinic. The traveler with a tick bite deep in the backcountry. Traveler’s diarrhea somewhere “go see someone” isn’t a real option for days. For those people, access is the binding constraint, not the diagnosis. And that is the only place a standby antibiotic earns its keep.

Notice it’s the same structure as the back-up prescription from a minute ago: a clinician deciding, in advance, that a drug is warranted only if a specific, recognizable condition is met, then putting it within reach for that moment. The back-up script solves for time. A standby kit solves for access. Same logic, same discipline, same requirement that a clinician drew the line first.

Which is exactly why that line has to be drawn narrowly, and why we’re loud about where it isn’t. A standby antibiotic is defensible only when two things are both true: self-recognition is reliable, and access is the real barrier. That points at a short list of access-tier drugs and clearly bounded indications: amoxicillin-clavulanate, doxycycline, metronidazole, for the worked-up recurrent UTI, the tick exposure, the giardiasis far from care. It points away from the respiratory complaints we spent this whole article cautioning about. Nobody should be carrying azithromycin to self-treat a cough or reaching for ciprofloxacin because their sinuses hurt. That’s the category where overdiagnosis already runs the show, and a kit there makes it worse, not better.

And we have to be candid about the risk, because pretending it away is how stewardship gets undermined. Just having antibiotics on hand is associated with using them more, and using them less appropriately, even among travelers who know better.⁸ That finding doesn’t kill the standby model. It sets the bar for it: the only version that survives that data is one where a clinician scoped the drug, the indication, and the “do not use this for X” before the patient ever walked out with it.

That discipline has a name. We call it appropriate medical preparation: the right drug, for the right indication, with a clear plan, and a clinician making the call. We’re a family team of physicians, PAs, and pharmacists, and it’s the standard we hold the JaseCase to. The kit removes the access barrier for the moment one is genuinely needed. It does not move the decision, and it is not a replacement for primary care, it’s for the times primary care isn’t reachable. If you’ve got patients who travel hard, live remote, or have a recurrent condition you’ve already worked up, you can point them to us at jase.com. And we’ll keep publishing where we draw these lines, and where we refuse to, so the framework is out in the open for the people who’d have to defend it.

The bottom line

Here’s where it all nets out. Most of the time, the patient in front of you who is certain they need an antibiotic doesn’t. The win isn’t a faster diagnosis or a stronger drug. It’s the right action at the right moment, and that action is usually one of three things (none of which is a rushed prescription): reassurance and a clear picture of what normal looks like, or symptom care plus a return plan, or “this one’s serious, let’s get you seen now.” Only in a narrow, pre-worked-out set of cases does it become “you already have what you need, and a clinician already decided when to use it.”

That’s what “having what you need” really means in the gray space. Not a pill for every bug. The judgment to tell the difference, the patience to wait when waiting is right, and the preparation so access is never the thing standing between a patient and the care they genuinely need. Get those three right and you’re practicing at the top of your training, even, and especially, on the days the answer won’t come clean.

That’s the discipline behind how we build, and how we’d ask anyone to build, a standby kit worth trusting.

Sources

1. Nicolle LE, et al. IDSA 2019 Clinical Practice Guideline for the Management of Asymptomatic Bacteriuria. Clin Infect Dis. 2019;68(10):e83-e110. Screening and treatment recommended only in pregnancy and before invasive urologic procedures; treating ASB otherwise drives inappropriate use. https://www.idsociety.org/practice-guideline/asymptomatic-bacteriuria/
2. Brown BD, Hood Watson KL. Cellulitis. StatPearls. Uncomplicated cellulitis improves within 24 to 48 hours of therapy; pain out of proportion to exam, rapid progression over hours, and systemic toxicity raise concern for necrotizing infection and warrant emergent evaluation. https://www.ncbi.nlm.nih.gov/books/NBK549770/
3. Choby BA. Diagnosis and Treatment of Streptococcal Pharyngitis. Am Fam Physician. 2009;79(5):383-390. Modified Centor: score 0-1 needs neither testing nor antibiotics; 2-3 warrants RADT or culture with treatment only if positive. https://www.aafp.org/pubs/afp/issues/2009/0301/p383.html
4. Harris AM, Hicks LA, Qaseem A. Appropriate Antibiotic Use for Acute Respiratory Tract Infection in Adults: Advice for High-Value Care From the ACP and the CDC. Ann Intern Med. 2016;164(6):425-434. No antibiotics for uncomplicated bronchitis unless pneumonia is suspected; antibiotics in rhinosinusitis only for severe or persistent (beyond ~10 days) symptoms; none for cold or influenza. https://www.acpjournals.org/doi/10.7326/M15-1840
5. Spurling GKP, Del Mar CB, Dooley L, et al. Delayed antibiotic prescriptions for respiratory infections. Cochrane Database of Systematic Reviews. 2017;9:CD004417. 11 trials, 3,555 participants; delayed prescribing reduces antibiotic use versus immediate, with no significant difference in complications and comparable patient satisfaction. https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.CD004417.pub5/full
6. Delayed antibiotic prescribing for respiratory tract infections: individual patient data meta-analysis. BMJ. 2021. 9 RCTs plus 4 observational studies, 55,682 patients; no difference in symptom severity delayed versus immediate, safe and effective for most including higher-risk subgroups, with slightly higher symptom severity only in children under 5. https://pmc.ncbi.nlm.nih.gov/articles/PMC8080136/
7. The Safety of Delayed Versus Immediate Antibiotic Prescribing for Upper Respiratory Tract Infections. Clin Infect Dis. 2021;73(2):e394-e401. 1.82 million patients; delayed prescribing associated with higher infection-related hospital admission (adjusted HR 1.52), with delayed prescriptions not well targeted to lower-risk patients, which underscores the need for case selection and clear return precautions. https://academic.oup.com/cid/article/73/2/e394/5864470
8. Kantele A, et al. Stand-by antibiotics encourage unwarranted use of antibiotics for travelers’ diarrhea: A prospective study. Travel Medicine and Infectious Disease. 2018;23:7-13. 316 travelers; carrying standby antibiotics raised antibiotic use to 34% versus 11% in non-carriers, with the excess driven by mild-to-moderate illness. https://pubmed.ncbi.nlm.nih.gov/29894796/