Valerian

Valerian (Valeriana officinalis) is a perennial herb native to Europe and Asia whose root has been used as a sedative since at least ancient Greek and Roman times — Hippocrates described its properties and Galen prescribed it for insomnia. The root contains a complex mixture of bioactive compounds including valerenic acid, isovaleric acid, and iridoids (valepotriates), which together modulate GABAergic neurotransmission by inhibiting GABA reuptake and degradation. Unlike benzodiazepines, valerian does not bind directly to GABA receptors but increases GABA availability in the synaptic cleft. Clinical evidence for valerian as a sleep aid is mixed but generally positive: systematic reviews suggest it modestly improves subjective sleep quality and may reduce the time to fall asleep, though polysomnographic studies show less consistent results. In Germany, valerian is an approved phytopharmaceutical (Phytostandard) and is commonly used as a gentle alternative to pharmaceutical sleep aids, particularly for nervous restlessness and mild sleep disturbances. It is not habit-forming and does not cause morning drowsiness at recommended doses.