Miconazole

Absorption

Miconazole given to healthy volunteers as a single 50 mg oral tablet produced a mean Cmax of 15.1 ± 16.2 mcg/mL, a mean AUC0-24 of 55.2 ± 35.1 mcg*h/mL, and a median Tmax of 7 hours (range 2.0-24.1). In these patients measurable plasma concentrations ranged from 0.5 to 0.83 mcg/mL.
Topical miconazole is absorbed poorly into the systemic circulation. In pediatric patients aged 1-21 months given multiple topical applications of miconazole ointment for seven days, the plasma miconazole concentration was less than 0.5 ng/mL in 88% of the patients, with the remaining patients having a concentration of 0.57 and 0.58 ng/mL, respectively. Similarly, patients. administered with a vaginal 1200 mg ovule had a mean Cmax of 10.71 ng/mL, mean Tmax of 18.4 hours, and mean AUC0-96 of 477.3 ng*h/mL.

Toxicity

Miconazole overdose has not been reported. Patients experiencing an overdose are at an increased risk of severe adverse effects such as headache, skin irritation, diarrhea, nausea, vomiting, abdominal pain, and dysgeusia. Symptomatic and supportive measures are recommended.
Miconazole has an oral LD50 of 500 mg/kg in rats.

Description

Miconazole, a derivative of imidazole, inhibits the biological production of ergosterol, a molecule needed by fungi to build their cell walls. Because of this, miconazole is widely used to treat yeast infections of the skin, throat, vagina, and the entire body. It is also used in some photographic development processes.

The Uses of Miconazole

Antifungal;Sterol 14-demethylase inhibitor.
Miconazole (Monistat-Derm, Micatin, etc.) is a synthetic imidazole antifungal compound that acts by altering cell membrane permeability. It is effective against most dermatophyte species, P. orbiculare, and C. albicans.

Background

Miconazole is a broad-spectrum azole antifungal with some activity against Gram-positive bacteria as well. It is widely used to treat mucosal yeast infections, including both oral and vaginal infections; although intravenous miconazole is no longer available, a wide variety of suppositories, creams, gels, and tablet-based products are available. Miconazole is thought to act primarily through the inhibition of fungal CYP450 14α-lanosterol demethylase activity.
Miconazole was first synthesized in 1969 and first granted FDA approval on January 8, 1974, for sale by INSIGHT Pharmaceuticals as a topical cream. It is currently available as a variety of prescription and over the counter products. Despite having been in clinical use for an extended period, resistance to miconazole among susceptible organisms is relatively low.

Indications

Miconazole is indicated for the local treatment of oropharyngeal candidiasis in adult patients and for the adjunctive treatment of diaper dermatitis complicated by candidiasis in immunocompetent patients aged four weeks and older. Miconazole is available as both a suppository and cream for the treatment of vaginal yeast infections and the relief of associated vulvar itching and irritation. Lastly, miconazole cream is effective in treating athlete's foot (tinea pedis), jock itch (tinea cruris), ringworm infections (tinea corporis), pityriasis (formerly tinea) versicolor, and cutaneous candidiasis.

What are the applications of Application

Miconazole is an antifungal inhibitor of CYP19 (aromatase)

Pharmacokinetics

Miconazole is an azole antifungal that functions primarily through inhibition of a specific demethylase within the CYP450 complex. As miconazole is typically applied topically and is minimally absorbed into the systemic circulation following application, the majority of patient reactions are limited to hypersensitivity and cases of anaphylaxis. Patients using intravaginal miconazole products are advised not to rely on contraceptives to prevent pregnancy and sexually transmitted infections, as well as not to use tampons concurrently.

Metabolism

Miconazole is metabolized in the liver and does not give rise to any active metabolites.