Doxepin and Valproic acid interaction
Doxepin and Valproic acid: both prescribing labels describe an interaction that usually calls for monitoring, a dose change, or spacing the doses.
Usually manageable with monitoring or a dose change. Tell your pharmacist you take both.
What the FDA labels say
From the Doxepin (Silenor) label · effective 2026-04-21
Although behaviors such as "sleep-driving" may occur with hypnotics alone at therapeutic doses, the use of alcohol and other CNS depressants with hypnotics appears to increase the risk of such behaviors, as does the use of hypnotics at doses exceeding the maximum recommended dose.
When taken with SILENOR, the sedative effects of alcoholic beverages, sedating antihistamines, and other CNS depressants may be potentiated [s ee Warnings and Precautions (5.2) and Drug Interactions (7.3 , 7.4) ].
From the Valproic acid label · effective 2024-05-02
In contrast, drugs that are inhibitors of cytochrome P450 isozymes, e.g., antidepressants, may be expected to have little effect on valproate clearance because cytochrome P450 microsomal mediated oxidation is a relatively minor secondary metabolic pathway compared to glucuronidation and beta-oxidation.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.