Amphotericin B is an antifungal medicine. Bayview compounds it for topical use in three different places: as preservative-free eye drops, as a nasal spray, and as a vaginal suppository or cream. None of these forms is sold as a manufactured product in the United States, so a licensed compounding pharmacy prepares them at the strength your prescriber orders.
These three uses are not equally well supported by research, and it would be misleading to describe them as if they were. The eye use is the best established. The vaginal use appears in infectious disease guidance for stubborn yeast infections. The nasal use has been studied in large trials and those trials were negative. Each section below says which is which.
How does it work?
Amphotericin B belongs to a group of antifungals called polyenes. It attaches to ergosterol, a fatty molecule that fungal cell membranes contain but human cell membranes do not. Once attached, it punches pores in the membrane so the contents of the fungal cell leak out and the cell dies. Because human cells use cholesterol instead of ergosterol, the drug targets the fungus far more than it targets you.
Amphotericin B is not absorbed to any meaningful degree across mucous membranes or the surface of the eye. That is the whole point of using it topically: the medicine stays where you put it and works locally, instead of circulating through the body.
What is it used for?
In the eye. Topical amphotericin B is used for fungal infections of the cornea (fungal keratitis), and it is most often chosen when the fungus is a yeast such as Candida. For mold-type fungi with branching filaments — Fusarium and Aspergillus — natamycin is generally the preferred first choice.
In the nose. Some ear, nose, and throat specialists prescribe amphotericin B nasal spray or nasal rinse for long-standing sinus inflammation thought to involve fungus. As explained below, the controlled research does not support this as a routine treatment.
In the vagina. Amphotericin B is prescribed for yeast infections that have not responded to the usual azole medicines such as fluconazole, especially infections caused by Candida glabrata. The 2016 Infectious Diseases Society of America candidiasis guideline lists topical 3% amphotericin B cream, alone or combined with 17% flucytosine cream for 14 days, among the options for azole-refractory C. glabrata vaginitis (IDSA candidiasis guideline).
Only a licensed prescriber can decide whether any of these uses is right for you. All of them are off-label, and a valid prescription is required.
What does the evidence show?
Eye — the strongest of the three. Topical amphotericin B is a long-recognized option for yeast keratitis. For filamentous fungi, the Mycotic Ulcer Treatment Trial (MUTT I) randomized 323 people with fungal corneal ulcers to topical natamycin 5% or topical voriconazole 1% and found natamycin gave better three-month vision, fewer corneal perforations, and better clearing of the fungus, with the advantage largest in Fusarium cases; the authors concluded voriconazole should not be used alone for filamentous keratitis (MUTT I). MUTT did not test amphotericin B, so it does not tell us how amphotericin B compares — but it is the reason natamycin remains the standard first choice for mold keratitis, and it is part of why amphotericin B is generally reserved for yeast.
Nose — the controlled evidence is negative. Please read this carefully. A Cochrane systematic review of antifungal therapy for chronic rhinosinusitis pooled seven placebo-controlled studies of topical antifungals in 437 people. None of them showed a statistically significant benefit for disease-specific quality of life or symptom severity, the certainty of the evidence was rated low to very low, and topical antifungals may cause more local irritation than placebo. The reviewers concluded it is uncertain whether antifungals have any effect on patient outcomes (Cochrane review). Bayview does not claim that amphotericin B nasal spray works for chronic sinus disease. Some specialists still prescribe it for selected patients, and that judgment belongs to your prescriber, not to us.
Vagina — guideline-supported but not first-line. The IDSA candidiasis guideline includes 3% amphotericin B cream as an option for azole-refractory C. glabrata vaginitis, alongside intravaginal boric acid 600 mg daily for 14 days and nystatin suppositories, and rates the amphotericin B option on lower-quality evidence than the alternatives. The CDC STI Treatment Guidelines section on vulvovaginal candidiasis recommends a longer course of a non-fluconazole azole for non-albicans yeast and, if it recurs, boric acid 600 mg vaginally daily for three weeks; the CDC section does not mention amphotericin B at all (CDC STI Treatment Guidelines). So this is a real, guideline-listed option — but it sits behind boric acid and nystatin, not ahead of them.
How do the forms and strengths compare?
Bayview compounds amphotericin B in several forms. The table describes them for education only; your prescriber chooses the form and strength.
| Form | Typical strengths | Notes |
|---|---|---|
| Preservative-free ophthalmic solution | 2, 3, or 5 mg/mL | Compounded sterile under USP <797>; refrigerated; short beyond-use dating |
| Nasal spray | 0.1% to 0.25% | Sprayed into the nose; evidence for chronic sinus disease is negative |
| Vaginal suppository | 50 mg or 100 mg | Used for azole-resistant yeast, most often C. glabrata |
| Vaginal cream or gel | 3% | The concentration named in the IDSA guideline, alone or with flucytosine |
| Custom | As ordered | Other strengths and volumes as your prescriber directs |
Forms and strengths are listed for education only and are not a statement that any one of them is better for a particular person. Your prescriber selects the preparation, strength, and schedule.
How is it used?
Use it exactly as your prescriber directs and finish the course they set. The instructions differ by form.
Eye drops. Wash your hands, tilt your head back, and instill the number of drops prescribed into the affected eye. Do not let the dropper tip touch your eye, your eyelid, or any surface, because that can contaminate the bottle. For a serious corneal infection the schedule can be very frequent at first, sometimes hourly around the clock, and your eye doctor will taper it. If you use more than one eye medication, wait about five minutes between them.
Nasal spray. Blow your nose gently first, then spray the prescribed number of sprays into each nostril as directed. Wipe the tip and recap it after use, and do not share the bottle.
Vaginal suppository or cream. Insert the prescribed dose vaginally as directed, usually at bedtime so it stays in place, for the number of days your prescriber specifies. A panty liner helps with leakage.
Do not stop early just because you feel better, and do not change the schedule on your own. A Bayview pharmacist is available if you have questions about your prescription.
Side effects & safety
Because topical amphotericin B is barely absorbed, side effects are usually limited to the area treated.
Eye drops commonly cause burning, stinging, redness, and blurred vision right after the drop goes in. Tell your eye doctor about worsening pain, increasing redness, or vision that gets worse rather than better. Compounded eye drops demand strict sterility: keep them refrigerated as labeled, never touch the dropper tip to anything, do not use a bottle that looks cloudy or discolored, and discard the bottle at the beyond-use date printed on your label even if medicine remains.
Nasal spray commonly causes nasal irritation, burning, dryness, sneezing, and nosebleeds. The Cochrane review found local irritation was more common with topical antifungals than with placebo.
Vaginal preparations commonly cause local irritation, burning, or itching, and some leakage.
Stop and seek care for signs of a serious allergic reaction such as rash, swelling of the face or throat, or trouble breathing.
Who should not use it?
Do not use it if you have had an allergic reaction to amphotericin B. Ophthalmic amphotericin B should not be used with contact lenses in place, and your eye doctor will usually tell you to leave lenses out entirely while a corneal infection is being treated. Vaginal preparations are generally avoided if you might be pregnant unless your prescriber specifically directs otherwise, and oil- or fat-based vaginal products can weaken latex condoms and diaphragms. Tell your prescriber about your full health history, allergies, pregnancy or breastfeeding status, and all other medicines, so they can decide whether this preparation is appropriate.
How should it be stored?
Store it exactly as your label directs. Amphotericin B preparations are normally refrigerated and must be protected from light, because the drug breaks down when exposed to light — keep the container in its carton or opaque bag and out of direct sunlight. Do not freeze. Keep it out of the reach of children, and do not share it. Compounded preparations carry a beyond-use date assigned according to USP <797> for sterile preparations or USP <795> for non-sterile preparations; that date is printed on your label. Do not use the preparation after that date, even if some is left, and dispose of unused medication as directed.
Why is this compounded?
Amphotericin B is manufactured in the United States only as a powder for intravenous infusion. There is no commercial eye drop, nasal spray, or vaginal suppository. Natamycin 5% (Natacyn) is the only FDA-approved topical antifungal for the eye, and it is indicated for fungal blepharitis, conjunctivitis, and keratitis (Natacyn label). When a prescriber wants amphotericin B for a yeast keratitis, a resistant vaginal yeast infection, or an intranasal trial, compounding is the only way to get it. As a 503A compounding pharmacy, Bayview prepares each order in small batches using quality ingredients — ophthalmic preparations sterile under USP <797>, non-sterile preparations under USP <795>. Compounded preparations are not FDA-approved.
Clinical details for prescribers
Regulatory status. Amphotericin B is not a controlled substance. No FDA-approved topical ophthalmic, intranasal, or intravaginal amphotericin B product exists in the US; natamycin 5% is the only FDA-approved topical ophthalmic antifungal. All topical uses are off-label and require compounding. Compounded preparations are not FDA-approved.
Formulations. PF ophthalmic solution 2, 3, and 5 mg/mL (5 mL and 10 mL); nasal spray 0.1–0.25% (15, 24, and 30 mL); vaginal suppositories 50 mg and 100 mg; 3% vaginal cream/gel (anhydrous base, 1 mL syringes). Ophthalmic preparations compounded under USP <797>; BUDs assigned per USP <797>/<795> and printed on the label. Refrigerate and protect from light.
Evidence & clinical points:
- Keratitis: topical amphotericin B is conventionally favored for yeast (Candida) keratitis; natamycin remains first-line for filamentous fungi. MUTT I (n=323) showed natamycin superior to voriconazole for filamentous ulcers, most markedly in Fusarium; MUTT II found no benefit from adding oral voriconazole. Neither trial included an amphotericin B arm.
- Chronic rhinosinusitis: Cochrane 2018 — seven RCTs, 437 participants, topical antifungal vs placebo; no statistically significant difference in disease-specific QoL or symptom severity; low to very low certainty; more local irritation. Routine use is not supported.
- Azole-refractory VVC: IDSA 2016 lists boric acid 600 mg PV daily ×14 d and nystatin 100,000 U PV daily ×14 d, with topical 17% flucytosine ± 3% amphotericin B cream ×14 d as a lower-evidence alternative for C. glabrata. CDC 2021 STI guidelines recommend a non-fluconazole azole ×7–14 d, then boric acid 600 mg PV daily ×3 weeks; they do not address amphotericin B.
- Negligible mucosal and corneal absorption — nephrotoxicity and infusion reactions associated with IV amphotericin B are not expected with topical routes.
Ordering: send a prescription to Bayview Pharmacy, 3844 Post Rd, Warwick, RI 02886 (NCPDP 4106882, fax 401-284-4506). Background: MUTT I; Cochrane, antifungals for chronic rhinosinusitis.
These are prescription compounded medications and are not FDA-approved. This information is educational and is not medical advice. Bayview Pharmacy does not provide consultations or determine whether a preparation is appropriate — your prescriber does that and sets the dose.
