This article discusses why antifungal medications are used, types of medications that may be prescribed, and some of the ways they might interact with psychiatric medications.

Overview of Antifungal Medication

Some antifungal drugs are designed to be taken orally. For example, to treat yeast infections in the mouth and throat, such as thrush. The risk of drug interaction is higher with oral antifungal drugs than the topical applications sold over the counter. There are dozens of over-the-counter medications for fungus, the best known including Lotrimin, Monistat, Lamisil, Tinactin, and Desenex. Lesser-known brands abound, and major drugstore chains often have their generic versions. The availability of antifungal medications makes it seem like they must be perfectly safe to use. In fact, if you look up “Lotrimin warnings,” you find that it says “no food and drug interactions have been reported.” Yet if you look deeper, you’ll find that there ​are known drug interactions and lots of them.

Active Ingredients in Antifungal Medication

The most common active ingredients in antifungal medications are:

ClotrimazoleMiconazoleTerbinafineTolnaftate

Some fungus treatments have other active ingredients such as ketoconazole and butenafine.

Common Antifungal Pills

Antifungal medications are prescribed under a variety of brand names. Some of the most commonly prescribed pills are:

Canesten (clotrimazole)Diflucan (fluconazole)Daktarin (ketoconazole)Lamisil (terbinafine)Oravig (miconazole)Nystan (nystatin)

In addition to oral antifungal medications, antifungals can also be administered topically or intravenously. How they are used often depends on the type of infection and its severity.

Interactions With Psychiatric Medications

All the “azoles” can interact with certain psychiatric medications when used regularly. For example:

Azoles used with Seroquel (quetiapine) can increase the plasma level to the point where the person using both may experience excessive drowsiness, fast or irregular heartbeat, dizziness, fainting, or extrapyramidal side effects. Azoles used with calcium channel blockers may cause such symptoms as swelling of the lower extremities, sudden, unexplained weight gain, difficulty breathing, chest pain or tightness, and dizziness or fainting. Ketoconazole used daily for 14 days increased the plasma concentration of Abilify (aripiprazole) about 70%. The product labels for Xanax (alprazolam) and Halcion (triazolam) both recommend against the use of any azole antifungal agent. Valium’s label specifically mentions ketoconazole. These drugs may cause a significant increase in blood plasma levels of trazodone.

This is just a sampling of the possible interactions of azole fungus treatments for conditions like athlete’s foot with psychiatric drugs. In addition, the active ingredient terbinafine can increase plasma levels of several antidepressants, particularly the tricyclics. Nortriptyline intoxication has been noted after steady use of terbinafine antifungals.

A Word From Verywell

Ask the pharmacist about possible interactions and/or check with your doctor. They may recommend that you use a treatment containing butenafine and tolnaftate, and/or it may be necessary to adjust the dosage of one or more medications you are currently taking during the time you need to use the antifungal treatment. If you are prescribed an oral antifungal drug, make sure your doctor knows about all your existing medications.