Econazole: a review of its antifungal activity and therapeutic efficacy

Econazole1 is a recently introduced imidazole antifungal agent which is very closely related structurally to another imidazole derivative, miconazole. For local application the nitrate salt of econazole is used, while in preliminary investigations of systemic use in a few patients econazole base has been administered orally or intravenously. In uncontrolled studies in large numbers of patients, econazole nitrate has been administered topically in the treatment of dermatomycoses due to a wide variety of fungi, and vaginally in the treatment of vaginal candidosis; but it has not been compared with any other antifungal drug in controlled therapeutic trials in mycoses of the skin and has only been compared with nystatin in a few patients with vaginal candidosis. Until adequate comparative studies are done the relative place of econazole in the treatment of dermatomycoses and vaginal condidosis, compared with traditional antifungal agents and with other imidazole derivatives such as miconazole or clotrimazole, cannot be clearly stated. Nevertheless, econazole nitrate is an effective antifungal drug. In dermatological studies about 90% of a large number of patients were cured, often after a relatively short treatment period (2 to 6 weeks, as occurs with other imidazole antifungal agents). The cure rate was only slightly lower (about 85%) in patients with severe mycoses of many years' duration than in those whose infections were of more recent onset. In vaginal candidosis a 3-day treatment regimen using a 150mg suppository once daily was only slightly less effective (85% mycological cure rate) than a 15-day regimen using a 50mg dose (suppository or cream) once daily (90% cure rate). A 3 to 5 day 'higher' dose regimen was slightly more effective than a standard 15-day regimen of nystatin vaginal inserts in a small group of patients with vaginal candidosis. The convenience of the higher-dose shorter term regimen would likely be an important advantage to most patients. Whether other agents useful in vaginal candidosis would be as effective as econazole were they to be used in this way, has not been determined. Topical or intravaginal econazole nitrate has usually been well tolerated, side effects being limited to local irritation in about 1 to 4% of patients in most studies.