For Clinicians | Sinusitis: When Antibiotics Are Necessary

By Dr. Jamie Wilkey, PharmD, Director of Clinical Education
Medically reviewed and edited by Kristen Carpenter, PA-C

Adult sinusitis guidance changed in July 2025, when the AAO-HNSF published its first guideline update since 2015 [AAO-HNSF 2025]. Three changes affect us in the office or at the pharmacy counter: watchful waiting is now the starting point for every uncomplicated case (yep, even once you’ve called it bacterial), amoxicillin with or without clavulanate is first-line on a shorter course, and a patient who isn’t improving gets reassessed sooner. Today we’re covering all three, plus the clause in the watchful-waiting recommendation that assumes your patient can come back.

What changed in the 2025 sinusitis guideline?

For an adult with uncomplicated acute bacterial sinusitis, waiting used to be one of two options. Now it’s where we start [AAO-HNSF 2025]:

• Watchful waiting became the default. Since 2015 we had the option either to offer watchful waiting or prescribe an antibiotic [AAO-HNSF 2015]. The 2025 version axes the “or prescribe”.  Offer watchful waiting without antibiotics, with assurance of follow-up. The fixed day count for when to start one is gone too. How long to wait now depends on when and how the diagnosis was made.
• The course got shorter. Amoxicillin with or without clavulanate stays first-line, for 5 to 7 days in most adults instead of 5 to 10.
• Treatment failure got redefined. It’s now judged against the antibiotic the patient is already taking. If it’s still bacterial, the solution is a different antibiotic.

You’re thinking, ok, but my patient is miserable and wants something today. They feel like it is a waste to leave our appointment without an Rx in-hand.  The guideline did address these folks: pain relievers, intranasal steroids, and saline irrigation are options for viral and bacterial sinusitis alike [AAO-HNSF 2025]. Those are also the three things a pharmacist can point to on the shelf when the patient asks for help with sinusitis.

When does sinusitis need an antibiotic?

Before writing that antibiotic script, check for one of two patterns. Neither changed in 2025 [AAO-HNSF 2025]:

• Symptoms that persist without improvement for at least 10 days after the cold starts.
• Symptoms that get better, then worse again within 10 days. (Double worsening)

Most of these patients never needed an antibiotic. Bacterial infection occurs in only 0.5 to 2 percent of episodes of acute rhinosinusitis, and acute bacterial rhinosinusitis may also be a self-limited disease³. It most commonly occurs as a complication of viral infection².

Mucus color isn’t on the list. Neither is how miserable the patient looks. Individual symptoms such as purulent nasal discharge or facial pain can’t accurately distinguish bacterial from viral sinusitis. Kristen Carpenter, PA-C, who reviewed this article, put it this way: “Fever and nasal discharge really don’t mean bacterial. Those symptoms can be viral too, so we don’t really give antibiotics just based on those symptoms. Everyone thinks they have a bacterial infection because of these things.” We covered why in our July article on bacterial vs. viral infection, so we won’t re-teach it here.

Where we struggle is applying the criteria. A Mayo Clinic cohort of adult sinusitis visits from early 2024 found that four of every five visits that didn’t meet any guideline criterion still ended with an antibiotic [Hannan 2026]. And the study counted generously: IDSA’s severe-onset pattern qualified too. The strongest predictor of an unneeded script was a patient on day 7, 8, or 9.

And I get it. Patients get so annoyed when we don’t give them that antibiotic right from the beginning. For them, day 8 of being sick feels like forever when you can’t breathe through your nose. Some of us (me, included) were trained on an older rule of thumb that anything past a week was probably bacterial. The 2025 guideline still draws the line at a full 10 days.

Some patients are worth starting earlier, and that comes down to their own history and health status. Kristen has a low threshold for starting antibiotics on the earlier side if the patient:

• Is immunocompromised (diabetes, etc.)
• Smokes
• Has uncontrolled asthma (maybe)
• Has a weird dental or nasal history
• Has had a recent change in atmospheric pressure (e.g., deep sea diving)

“I’m sure there are others,” she says, “but again it would be based on some individual health status.”

Amoxicillin or Augmentin for a sinus infection? (And why not the Z-Pak)

Once a patient meets criteria and an antibiotic is the right call, then focus on amoxicillin or amoxicillin-clavulanate [AAO-HNSF 2025]. Either one is first-line. For a penicillin allergy, IDSA lists doxycycline as an alternative [IDSA 2012].

What we shouldn’t reach for is the Z-Pak. At the office or the pharmacy counter, it’s the antibiotic patients ask for by name, because it’s short, it’s easy, and “it worked last time”. (Or the last sinus infection was viral and got better on its own, Z-Pak or no Z-Pak.) IDSA recommends against macrolides for empiric sinusitis therapy because resistance rates are too high. They’re not alone. TMP-SMX is on the same list for the same reason [IDSA 2012]. Fluoroquinolones carry their own limit: since 2016, FDA has said to reserve them for acute sinusitis when no other option exists [FDA 2016].

A patient who isn’t better, or is worse, after 3 to 5 days on an appropriate antibiotic gets reassessed: confirm it’s still bacterial sinusitis, look for another cause, and check for complications [AAO-HNSF 2025]. If it’s still ABRS, switch the antibiotic. That’s the ideal follow up visit.

When the clinic isn’t reachable

Watchful waiting comes with a condition: assurance of follow-up [AAO-HNSF 2025]. The recheck is the safety net. It catches the patient who crosses into a bacterial pattern and the rare one heading toward a complication.

Most of us read past that clause, because most of our patients can come back. Some can’t, and some can’t get in the first time either. The patient on an international trip, the family at a remote cabin, the town where a storm closes the clinic.

Here’s what makes sinusitis different from strep: the diagnosis rests on the history and the calendar. There’s no rapid test to run, and an uncomplicated case doesn’t need imaging [AAO-HNSF 2025]. So no clinic doesn’t have to mean no clinician. A phone or telehealth visit can apply the same two patterns, at the first visit or the second.

Whichever visit is missing, the counseling has to do its job ahead of time, at the office or the pharmacy counter. In plain words:

• The two patterns: no improvement by day 10, or better and then worse. Either one means it’s time to reach a clinician, by phone or telehealth if that’s what they have.
• The signs that mean go now, wherever they are: swelling around the eye, changes in vision, a severe headache, confusion, a stiff neck, or a high fever that won’t come down [IDSA 2012].

A patient who already has a prescribed antibiotic at home doesn’t get a different standard. It’s for emergency use only, after first seeking help from a qualified healthcare provider, and the two patterns still decide whether it’s needed.

None of this is a reason to start sooner. Distance from a clinic isn’t on Kristen’s list, and the 10-day line holds wherever the patient is.

Holding our own guidance to the update

We’re a family team of medical doctors, PAs, and pharmacists, and we hold our own guidance to the same update. The Jase amoxicillin-clavulanate card reads 5 to 7 days for sinusitis, and it did before the 2025 guideline made that the standard.

The bigger work is the part this guideline hands to a visit the patient may not be able to make. Right now care runs all or none: the patient gets in, or they’re on their own with an internet search bar and a leftover Z-Pak. Appropriate medical preparation is the step between. It’s clinical work done ahead of time. For sinusitis, that work is mostly teaching patients to count the days, and most of them will be better before they reach 10[IDSA 2012]. It’s in no way a replacement for primary care. We’re here for the times when primary care isn’t there, and we’ll keep publishing how we draw these lines so you can check our work.

The bottom line

The 2025 update kept the diagnosis and changed the default: wait first, with follow-up, and keep the course short when an antibiotic is needed. For most patients, the hardest stretch is days 7 through 9, when they’re tired of being sick and we’re tempted to start antibiotics too early.

Sources

1. Payne SC, McKenna M, Buckley J, et al. Clinical Practice Guideline: Adult Sinusitis Update. Otolaryngol Head Neck Surg. 2025;173(Suppl 1):S1-S56. https://doi.org/10.1002/ohn.1344
2. Rosenfeld RM, Piccirillo JF, Chandrasekhar SS, et al. Clinical practice guideline (update): adult sinusitis. Otolaryngol Head Neck Surg. 2015;152(2 Suppl):S1-S39. https://doi.org/10.1177/0194599815572097
3. Arensman Hannan K, Ilges D, Le KT, Cole K, Stevens RW, Jensen K. Ambulatory antibiotic prescribing for acute sinusitis: a multicenter, retrospective cohort study evaluating appropriateness. Antimicrob Steward Healthc Epidemiol. 2026;6(1):e193. https://doi.org/10.1017/ash.2026.10743
4. Chow AW, Benninger MS, Brook I, et al. IDSA clinical practice guideline for acute bacterial rhinosinusitis in children and adults. Clin Infect Dis. 2012;54(8):e72-e112. https://doi.org/10.1093/cid/cis370
5. U.S. Food and Drug Administration. CIPRO (ciprofloxacin hydrochloride) prescribing information, section 1.12, Acute Sinusitis. Revised July 2016. https://www.accessdata.fda.gov/drugsatfda_docs/label/2016/019537s086lbl.pdf

For Clinicians | New World Screwworm in Humans: The Wound Check, the Larvae, and the Risk

By Dr. Jamie Wilkey, PharmD, Director of Clinical Education
Medically reviewed and edited by Kristen Carpenter, PA-C

New World screwworm is the latest health headline. This one came from an elk in Texas. On October 21, USDA confirmed the parasite in an elk on a Pecos County game ranch, the first US wildlife case of this outbreak¹. We don’t ride the hype wagon that turns every news story into a healthcare emergency, and CDC still rates the risk to the US public as very low². But when our clinical team reviewed the cases, we were kind of struck by who this has actually reached. The people who’ve gotten it look a lot like the patients we serve at Jase.

Fair warning: this article isn’t for the squeamish. We’re talking about maggots in wounds. You’re clinicians, so we know you can handle it.

Today we’re covering who’s actually at risk for screwworms in the US, what an infested wound looks like, what to do with the larvae, and what antibiotics can and can’t do. 

Can people in the US get New World screwworm?

Yes, but only in one very specific and super gross way. A female fly lays her eggs on an open wound or a mucous membrane, and the larvae hatch and burrow in to feed on living flesh³. Most maggots you’ve seen in a wound stay up on the surface. These go deep deep deep, which is the problem.

The fly is the only route. Screwworm doesn’t pass from person to person, and nobody catches it from an infested animal⁴. So the clinical question is narrow: does this patient have an open wound somewhere the flies are? Right now that means parts of Texas and New Mexico, plus travel to Mexico or Central America. And CDC means any open wound, even a scratch, an insect bite, or a recent surgical site³.

That elk that is all over the headlines these days is why we’re writing now. Wildlife is harder to track and control than cattle, and CDC listed wildlife detection as one of the developments that would change its risk assessment⁴. Whether cold weather holds the fly back this winter is still an open question.

Screwworm finds older patients with chronic wounds

Clinicians, you won’t be surprised that most of these infestations are on the legs and feet. If something is eating a patient’s foot and they don’t know it, our brains go straight to the likely reasons. They probably can’t feel it because of diabetic neuropathy, or they have a hard time reaching or seeing that part of their body. A heel or the back of a calf is easy to miss when bending over is hard, and a diabetic foot ulcer or a venous stasis ulcer can stay open for months. That gives the fly both things it needs: an open wound and time.

The people actually at risk look exactly like that. In Mexico’s 202 confirmed human cases between April 2025 and March 2026, the average patient was 61, most had at least one chronic condition (diabetes was the most common), and more than half of the infestations were on the legs or feet⁵. CDC describes the same group: older adults and people with limited mobility, whose infestations can go unnoticed until treatment is late⁴. The deaths in the Mexico series happened in even older patients, and the authors attributed only one of the six directly to the larvae⁵.

These patients aren’t necessarily frail, either. Plenty of them still work cattle, hunt every fall, or spend the winter in South Texas, and they just don’t notice a wound on a foot they can’t feel. In the office, that means taking the sock off and looking at the feet of your patients with diabetes who live in or travel to these areas. At the pharmacy counter, it means asking a few questions when someone buys dressings for a foot or leg wound that won’t heal and has started to smell.

What does an infested wound look like, and what do you do with the larvae?

You’ll probably smell it before you see it. Texas health officials describe a very painful, foul-smelling wound with visible larvae, sometimes with an egg mass in or around the wound or a body opening, and often more tissue damage underneath than the surface suggests⁶. When a wound like that shows up in a patient who lives in, works in, or recently traveled through an area with the fly, screwworm belongs on your list.

The protocol from there is short:

• Remove every larva. They burrow deep, so the ones you can see are not all of them, and getting the rest out may take surgical debridement⁶.
• Collect larvae from different depths of the wound and drop them into a leak-proof container with enough 70% ethanol to cover them⁶.
• Never throw live larvae in the trash or on the ground. Kill them in the alcohol, then dispose of the sealed container as medical waste, because a live larva in the dumpster is how the fly gets a new foothold⁶.
• Recheck the wound in 24 to 48 hours to make sure nothing in there is still alive⁶.
• Call your local or state health department right away. Texas treats a suspected case as immediately reportable, and the health department will help get the larvae identified⁶. Reporting rules vary by state, so check yours.

For patients with open wounds, your front desk or MA can add one intake question: have you been in Texas, New Mexico, Mexico, or Central America recently? At the pharmacy counter, send the patient to be seen that same day and tell them not to pick the maggots out at home. CDC says patients shouldn’t try, since getting every larva out can take a clinician and sometimes surgery².

What can antibiotics do for screwworm?

Antibiotics do less here than patients will hope. Larvae aren’t bacteria, so an antibiotic does nothing to the infestation itself. What it can treat is a secondary bacterial infection in a wound that’s been chewed open, and Texas health officials remind clinicians that it may need antibiotic therapy⁶. That call follows the same logic as any other infected wound, starting with whether you’re looking at a purulent pocket or a spreading cellulitis.

Nothing treats the larvae themselves. CDC says no licensed human vaccine or medication currently prevents or treats screwworm in people⁴. The treatment with evidence behind it is the protocol above: get every larva out and keep caring for the wound.

Your patients may have read otherwise, because there are plenty of guesses online that whatever works on cattle will work on people. Don’t follow treatment advice that comes only from social media or forums. Stick with what the medical literature has shown to be safe and effective in humans. For screwworm, that’s still a clinician with nerves of steel and a pair of tweezers.

The bottom line: the wound nobody’s checking

Right now, care for a wound like this is all or nothing. Either a clinician sees it, or the patient is alone with a sore on a foot they can’t feel. The step in between is counseling. Tell your patients in fly areas to wash open wounds with soap and running water, keep every wound covered, even a tiny scratch or a bug bite², check their feet and legs every day, and get seen the same day if they ever see or feel maggots. 

For patients who spend long days outside, like hunters, ranchers, and anyone working cattle, add the fly side of it. CDC recommends loose-fitting long sleeves and pants, a hat, and socks, clothing and gear treated with a 0.5% permethrin product (the kind made for fabric, not skin), an EPA-registered insect repellent, and sleeping indoors or somewhere screened². Fall hunting season is a good time to bring it up.

That’s appropriate medical preparation, with no prescription anywhere in it. It complements the primary care you’re already giving, and it covers the stretch between visits when nobody else is looking at that foot.

The health risk to the US public is very low, and the patients who are actually at risk are a narrow group you already know. The protocol is short, and no drug treats the larvae. We’ll keep publishing how we think through headlines like this one, so you have a clear clinical picture to point to when your patients bring them in or pepper you with questions from what they’re reading.

Sources

1. USDA Animal and Plant Health Inspection Service. USDA Confirms First Detection of New World Screwworm in U.S. Wildlife. October 21, 2026. https://www.aphis.usda.gov/news/agency-announcements/usda-confirms-first-detection-new-world-screwworm-us-wildlife
2. Centers for Disease Control and Prevention. New World Screwworm Outbreak. Updated October 22, 2026. https://www.cdc.gov/new-world-screwworm/situation-summary/index.html
3. Centers for Disease Control and Prevention. Clinical Overview of New World Screwworm. Updated February 24, 2026. https://www.cdc.gov/new-world-screwworm/hcp/clinical-overview/index.html
4. Centers for Disease Control and Prevention. Risk to People in the United States from the New World Screwworm Outbreak (2026). Assessment as of October 7, 2026. https://www.cdc.gov/cfa-qualitative-assessments/php/data-research/risk-to-people-in-the-united-states-from-the-new-world-screwworm-outbreak-2026.html
5. Delgado-Cuellar O, Mosso-González C, Castañeda-Gómez J, et al. Human Myiasis Resulting from Reemergence of Cochliomyia hominivorax Screwworm, Mexico, 2025-2026. Emerg Infect Dis. 2026;32(10):1581-1589. https://wwwnc.cdc.gov/eid/article/32/10/26-1235_article
6. Texas Department of State Health Services. New World Screwworm Information for Healthcare Providers. Accessed October 26, 2026. https://www.dshs.texas.gov/notifiable-conditions/zoonosis-control/zoonosis-control-diseases-and-conditions/new-world-screwworm/new-world-screwworm-information-healthcare-providers