Which drug increases zolpidem tartrate levels when taken together?

Zolpidem tartrate, a common medication for the treatment of insomnia, is primarily metabolized by the liver enzyme CYP3A4. When taken in combination with azole antifungals, such as ketoconazole or itraconazole, the levels of zolpidem can increase significantly. Azole antifungals are known to inhibit CYP3A4, leading to decreased metabolism of drugs that are substrates of this enzyme.

This interaction is clinically significant because increased levels of zolpidem can enhance its sedative effects, potentially leading to increased risk of side effects such as excessive sedation, confusion, and impaired coordination. Therefore, when a patient is taking an azole antifungal alongside zolpidem, careful monitoring is necessary to avoid these adverse effects.

In contrast, rifampin is a potent inducer of CYP450 enzymes and would generally decrease zolpidem levels, while melatonin agonists and nitrous oxide do not have a significant interaction with zolpidem that would increase its levels. Understanding these interactions is crucial for safe prescribing practices and patient management.