Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
AMPHOTERICIN B vs GYNIX
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Binds to ergosterol in fungal cell membranes, forming pores that increase permeability and cause leakage of intracellular contents, leading to cell death.
Coagulative necrosis of tissue via trichloroacetic acid; chemical cauterization of epithelial cells.
Aspergillosis,Blastomycosis,Candidiasis,Coccidioidomycosis,Cryptococcosis,Histoplasmosis,Mucormycosis,Sporotrichosis,Visceral leishmaniasis,Empiric therapy for febrile neutropenia,Meningitis (cryptococcal, coccidioidal)
Cervical inflammation,Vaginal infections,Treatment of genital warts,Chemical cautery of skin lesions
0.5-1.5 mg/kg/day IV over 2-6 hours; for invasive aspergillosis, 1 mg/kg/day; for cryptococcal meningitis, 0.7 mg/kg/day IV in combination with flucytosine; liposomal formulation: 3-5 mg/kg/day IV. Maximum dose: 1.5 mg/kg/day for conventional amphotericin B deoxycholate.
1 vaginal tablet (100 mg) once daily at bedtime for 7 days
Terminal half-life: 24–48 hours initially, prolonged to 15 days with repeated dosing due to tissue redistribution.
Terminal half-life is 2.5-3 hours in patients with normal renal function; prolonged to 6-8 hours in moderate renal impairment (Cr Cl 30-50 m L/min) and up to 12-15 hours in severe renal impairment (Cr Cl <30 m L/min).
Primarily hepatic; exact enzymes not well characterized.
Not metabolized; acts locally via direct chemical action.
Renal: ~2-5% unchanged; biliary/fecal: ~40% as metabolites; extensive tissue binding delays excretion.
Primarily renal (approximately 60-80% as unchanged drug) and biliary (20-30% as metabolites; unchanged drug not detected in bile). Fecal elimination accounts for <5%.
90–95% bound, primarily to albumin and alpha-1-acid glycoprotein.
Approximately 20-30% bound to albumin with negligible binding to alpha-1-acid glycoprotein.
4–5 L/kg (extensive tissue binding, especially in liver, spleen, and lungs).
Apparent Vd is 0.8-1.1 L/kg (range 0.6-1.3 L/kg), indicating extensive tissue distribution (e.g., lung, liver, bone).
IV: 100%; oral: <5%; topical: minimal systemic absorption.
Oral: 85-95% (immediate-release) and 70-80% (sustained-release due to first-pass effect). Vaginal: 5-10% (minimal systemic absorption). IV: 100%.
Acute kidney injury: consider dose reduction or switch to liposomal formulation. No specific GFR-based dose adjustments for conventional formulation; monitor renal function and electrolytes. For liposomal amphotericin B, no dosage adjustment required for renal impairment. Continuous renal replacement therapy: conventional amphotericin not recommended due to nephrotoxicity; liposomal preferred.
No dose adjustment required for GFR ≥30 m L/min. For GFR <30 m L/min: use with caution, consider alternative therapy.
No specific Child-Pugh based dose adjustments. Use caution in hepatic impairment; monitor liver function tests. Dose adjustment not typically required.
Mild to moderate hepatic impairment (Child-Pugh A or B): no adjustment. Severe (Child-Pugh C): contraindicated.
Conventional amphotericin B: 0.25-1.5 mg/kg/day IV; initial test dose 0.1 mg/kg. Liposomal amphotericin B: 3-5 mg/kg/day IV. For neonates: 1 mg/kg/day. Maximum daily dose: 1.5 mg/kg for conventional, 5 mg/kg for liposomal.
Not approved for use in pediatric patients.
Use with caution due to age-related renal function decline; monitor renal function and electrolyte levels carefully. Same dosing as adults; adjust for renal impairment if present. Lower doses may be considered based on clinical status.
No dose adjustment required; use same as adult dosing.
Amphotericin B should be used primarily for progressive, potentially life-threatening fungal infections; it is not intended for non-invasive forms of fungal disease. It should be used under close medical supervision due to potential toxicity.
None.
Monitor renal function, electrolytes, and liver function; risk of nephrotoxicity, hypokalemia, hypomagnesemia, and infusion-related reactions; caution in patients with renal impairment and those receiving other nephrotoxic drugs.
Avoid contact with normal tissue; risk of chemical burns; not for use on neoplastic lesions.
Hypersensitivity to amphotericin B or any component of the formulation; unless the potential benefit outweighs the risk.
Hypersensitivity to trichloroacetic acid; pregnancy (relative); use on malignant tissue.
Avoid excessive salt intake; monitor for hypokalemia and hypomagnesemia. No specific food restrictions but maintain adequate hydration.
No known food interactions with topical use. However, avoid concurrent use of iodine-containing supplements or medications, as it may increase systemic iodine load.
FDA Pregnancy Category B. Animal studies show no evidence of fetal harm; no adequate human studies in first trimester. Use during pregnancy only if clearly needed. Limited data suggest no increased risk of major malformations across all trimesters.
First trimester: Inadequate human data; animal studies not available. Theoretical risk based on pharmacologic action. Second and third trimesters: No known fetal harm from topical use. Systemic absorption minimal.
Excreted in breast milk in low levels; M/P ratio not established. Consideration of benefits vs risks; caution in nursing infants due to potential for oral absorption and adverse effects.
No data on excretion in human milk. Expected minimal systemic absorption. Use caution if applied to breast area. M/P ratio unknown.
No specific dose adjustments recommended in pregnancy; standard dosing based on indication and patient weight. Pharmacokinetic changes in pregnancy (increased Vd, increased clearance) may theoretically require higher doses, but clinical data insufficient to recommend adjustment.
No dose adjustment necessary for topical use. Systemic absorption negligible.
Premedicate with acetaminophen, diphenhydramine, and hydrocortisone to reduce infusion-related reactions. Monitor serum potassium and magnesium closely due to renal wasting. Use normal saline bolus before infusion to reduce nephrotoxicity. Lipid formulations allow higher doses with less nephrotoxicity. Amphotericin B deoxycholate is reserved for severe, refractory cases.
GYNIX (povidone-iodine) is a topical antiseptic. Avoid use in patients with iodine hypersensitivity or thyroid disorders (e.g., Hashimoto's thyroiditis). Prolonged use on large wounds may cause iodine absorption and thyroid dysfunction. Monitor for local irritation or allergic contact dermatitis.
You may experience fever, chills, and nausea during infusion; these are common and can be managed with premedications.,Report any signs of kidney problems such as decreased urine output, swelling in legs, or fatigue.,Avoid potassium and magnesium supplements unless prescribed, as levels may fluctuate.,This medication can cause low blood pressure during infusion; rise slowly from sitting or lying down.,Complete the full course even if you feel better to prevent the infection from returning.
Do not use if you are allergic to iodine or have a thyroid condition.,For external use only. Avoid contact with eyes, mouth, or open wounds unless directed.,Discontinue and inform your doctor if you develop rash, itching, or swelling.,Store at room temperature away from light. Do not freeze or heat.,Not for use on deep or puncture wounds, or severe burns without medical advice.
"Efinaconazole, a triazole antifungal, inhibits fungal CYP450-dependent lanosterol 14α-demethylase, reducing ergosterol synthesis. Amphotericin B binds to ergosterol in fungal membranes, forming pores that cause cell death. Concomitant use may decrease Amphotericin B efficacy because efinaconazole depletes ergosterol, the target for Amphotericin B, potentially attenuating the polyene's antifungal activity, especially in systemic fungal infections."
"Gentamicin, an aminoglycoside antibiotic, and Amphotericin B, a polyene antifungal agent, both independently induce nephrotoxicity. Concurrent administration synergistically increases the risk of acute kidney injury, characterized by elevated serum creatinine, reduced glomerular filtration rate, and potential tubular necrosis. This additive nephrotoxic effect necessitates cautious use and enhanced monitoring."
"Amphotericin B, a polyene antifungal, can cause hypokalemia and hypomagnesemia due to renal tubular damage. Isradipine, a calcium channel blocker, may also affect electrolyte balance. Concomitant use increases the risk of severe hypokalemia, potentially leading to cardiac arrhythmias, QT prolongation, and neuromuscular effects. Close monitoring of serum electrolytes and ECG is essential."
No interactions on record
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about AMPHOTERICIN B vs GYNIX, answered by our medical review team.
AMPHOTERICIN B is a Antifungal that works by Binds to ergosterol in fungal cell membranes, forming pores that increase permeability and cause leakage of intracellular contents, leading to cell death.. GYNIX is a Polyene Antifungal that works by Coagulative necrosis of tissue via trichloroacetic acid; chemical cauterization of epithelial cells.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between AMPHOTERICIN B and GYNIX depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of AMPHOTERICIN B is: 0.5-1.5 mg/kg/day IV over 2-6 hours; for invasive aspergillosis, 1 mg/kg/day; for cryptococcal meningitis, 0.7 mg/kg/day IV in combination with flucytosine; liposomal formulation: 3-5 mg/kg/day IV. Maximum dose: 1.5 mg/kg/day for conventional amphotericin B deoxycholate.. The standard adult dose of GYNIX is: 1 vaginal tablet (100 mg) once daily at bedtime for 7 days. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between AMPHOTERICIN B and GYNIX in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. AMPHOTERICIN B is classified as Category C. FDA Pregnancy Category B. Animal studies show no evidence of fetal harm; no adequate human studies in first trimester. Use during pregnancy only if clearly needed. Limited data sug. GYNIX is classified as Category C. First trimester: Inadequate human data; animal studies not available. Theoretical risk based on pharmacologic action. Second and third trimesters: No known fetal harm from topical . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.