Inc. Kirkland Signature Sleep Aid's active ingredient, doxylamine succinate, is a well-known antihistamine that's also found in Unisom Sleeptabs. Although this sleep aid is considered safe for ...

Potentiates CNS depression with alcohol, other CNS depressants. Concomitant other diphenhydramine- or doxylamine-containing products (including topicals): not recommended. Additive effects with ...