[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Pharmacology](https://durgical.com/en/pharmacology/) › [Azole antifungals](https://durgical.com/en/pharmacology/classes/azole-antifungals/) › Clotrimazole [Pharmacology](https://durgical.com/en/pharmacology/) · [Azole antifungals](https://durgical.com/en/pharmacology/classes/azole-antifungals/) # Clotrimazole Imidazole antifungal used on the skin, in the vagina and as a mouth lozenge for Candida and ringworm. Very little reaches the blood. Updated 2026-11-01 - Class: [Azole antifungals](https://durgical.com/en/pharmacology/classes/azole-antifungals/) - Enzyme: Lanosterol 14α-demethylase (CYP51, the fungal ERG11 enzyme) - ATC code: G01AF02 - WHO Model List of Essential Medicines ✂**Lanosterol 14α-demethylase (CYP51, the fungal ERG11 enzyme)**Clotrimazole ⓘ The figure shows clotrimazole bound to CYP51 from the amoeba Acanthamoeba castellanii; the fungal enzyme has the same sterol-demethylase site. **Target in 3D:** Lanosterol 14α-demethylase (CYP51, the fungal ERG11 enzyme). PDB structure 6UW2 (RCSB PDB, public domain). [View the structure at RCSB PDB](https://www.rcsb.org/structure/6UW2) · Drag to rotate · pinch to zoom ## Mechanism of action Clotrimazole inhibits the sterol 14α-demethylase of yeasts and dermatophytes and alters the permeability of the fungal membrane. It is fungistatic at usual concentrations and may be fungicidal against Candida at higher ones. - Clotrimazole blocks the fungal sterol demethylase - The membrane loses ergosterol and becomes leaky - Yeast and dermatophyte growth stops where it is applied ## Pharmacokinetics **Absorption** Minimal: lozenges give very low blood levels; a small fraction of a vaginal dose is absorbed. **Distribution** After a lozenge dissolves, active levels persist in saliva for a few hours, released slowly from the oral mucosa. ## Indications - Vulvovaginal candidiasis (vaginal cream or tablets). [Vulvovaginal candidiasis →](https://durgical.com/en/conditions/vulvovaginal-candidiasis/) - Oropharyngeal candidiasis and its prevention in immunocompromised patients (lozenges). [Candidiasis: oral, oesophageal and invasive →](https://durgical.com/en/conditions/candidiasis-oral-oesophageal-and-invasive/) - Tinea corporis, tinea cruris and tinea pedis (cream or solution). [Dermatophytosis (tinea) and onychomycosis →](https://durgical.com/en/conditions/dermatophytosis-and-onychomycosis/) - Cutaneous candidiasis. [Cutaneous and mucocutaneous candidiasis →](https://durgical.com/en/conditions/cutaneous-and-mucocutaneous-candidiasis/) ## Adverse effects ### Common - Lozenges: nausea, vomiting, unpleasant mouth sensation, itching - Lozenges: mildly raised AST - Vaginal: burning, itching or irritation - Skin: redness, stinging, peeling ### Serious (rare, important) - Allergic skin reactions with blistering or hives (rare) ## Contraindications - Hypersensitivity to any component - Lozenges are not for systemic mycoses ## Key interactions **Latex condoms and diaphragms** Vaginal clotrimazole can weaken them, so they may fail to prevent pregnancy or sexually transmitted infections. ## What is monitored - Clinical response of the lesions - Liver tests periodically with long lozenge use ## Administration and safety - Lozenges must dissolve slowly in the mouth, without chewing, crushing or swallowing them; the patient must be able to follow this. - Confirm oral candidiasis with a KOH smear or culture before treatment. - Vaginal forms: warn that latex condoms and diaphragms may fail during treatment. ## Nursing care - Inspect the mouth, skin or vulva before and during treatment. - Teach to complete the course even if symptoms fade. - Vaginal yeast infection does not cause fever, pelvic pain or foul discharge: those need medical review. ## Pregnancy and breastfeeding Embryotoxic in animals only at oral exposures far above human use and not teratogenic; lozenges are used in pregnancy only if the benefit justifies the risk. ## Memory aid «CLOTrimazole CLOTHES the mucosa»: it stays on skin, vagina and mouth, not in the blood. ## Test yourself Think of the answer, then tap the question to see it. ## How must clotrimazole lozenges be taken to work? Dissolved slowly in the mouth so that the drug coats the mucosa and stays in the saliva. ## What contraceptive warning goes with vaginal clotrimazole? It can weaken latex condoms and diaphragms, which may then fail. ## Is clotrimazole an imidazole or a triazole? An imidazole, like miconazole and ketoconazole. [Add to my cards (3)](https://durgical.app/estudiar/?add=/en/pharmacology/clotrimazole/) ## Related drugs - [Miconazole](https://durgical.com/en/pharmacology/miconazole/) - [Nystatin](https://durgical.com/en/pharmacology/nystatin/) - [Fluconazole](https://durgical.com/en/pharmacology/fluconazole/) ## Related conditions - [Vulvovaginal candidiasis](https://durgical.com/en/conditions/vulvovaginal-candidiasis/) - [Candidiasis: oral, oesophageal and invasive](https://durgical.com/en/conditions/candidiasis-oral-oesophageal-and-invasive/) - [Dermatophytosis (tinea) and onychomycosis](https://durgical.com/en/conditions/dermatophytosis-and-onychomycosis/) - [Cutaneous and mucocutaneous candidiasis](https://durgical.com/en/conditions/cutaneous-and-mucocutaneous-candidiasis/) [← Back to the class: Azole antifungals](https://durgical.com/en/pharmacology/classes/azole-antifungals/) Educational content on how drugs work; not a prescribing guide and no substitute for a health professional's advice. No doses are given. Sources: [DailyMed - CLOTRIMAZOLE lozenge](https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=980736aa-751a-4642-ab85-a309435fd02f) (DailyMed (U.S. National Library of Medicine), 2025); [Clotrimazole Vaginal: MedlinePlus Drug Information](https://medlineplus.gov/druginfo/meds/a682753.html) (MedlinePlus (U.S. National Library of Medicine), 2023); [Clotrimazole Topical: MedlinePlus Drug Information](https://medlineplus.gov/druginfo/meds/a618059.html) (MedlinePlus (U.S. National Library of Medicine), 2018); Goodman & Gilman's The Pharmacological Basis of Therapeutics, 14th ed., ch. 61 (McGraw Hill, 2023). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/pharmacology/clotrimazole/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/pharmacology/clotrimazole/