Valerian Interactions

Valerian root contains valerenic acid and other compounds that modulate GABA-A receptor activity. Combined with lorazepam, a benzodiazepine that also enhances GABA signaling, the effect is additive CNS depression with increased risk of severe drowsiness, confusion, and impaired coordination.

Zolpidem is a Z-drug hypnotic that selectively binds the GABA-A receptor's alpha-1 subunit. Valerian's valerenic acid also modulates GABA-A receptors, producing additive sedation and a documented delay in next-morning psychomotor recovery when the two are combined.

Diphenhydramine (a sedating antihistamine) and valerian root both produce CNS depression through GABAergic and histaminergic pathways. Used together, sedation, psychomotor impairment, and respiratory depression risks are additive.

Valerian root acts on GABA-A receptors and may inhibit GABA breakdown, producing sedative effects that are additive with alcohol's CNS depressant effects. The combination produces increased drowsiness, impaired psychomotor performance, and risk of falls, particularly in older adults.

Lemon balm (Melissa officinalis) and valerian (Valeriana officinalis) both modulate the GABAergic system but through different mechanisms — valerian's valerenic acid acts directly on GABA-A receptors while lemon balm's rosmarinic acid inhibits GABA transaminase to preserve GABA in the synapse — and the combination has been studied for restlessness, dyssomnia, and sleep quality.