Part used: fresh or recently dried root and rhizome
Herbal action: sedative, nervine relaxant, antispasmodic, hypotensive, anodyne, carminative
Indications: insomnia, restless, irritability, anxiety, headache, intestinal colic, rheumatism, dysmenorrhea
Medicinal uses: Valerian is one of the better relaxant for nerves and muscle, but in large doses, or in some sensitive people (or cats), it can have the opposite effect. It can cause nervousness, restlessness, wakefulness and twitching followed by drowsiness, sleepiness, lessened sensibility and relaxation. I have seen many people overdo Valerian and both become dependent on it and get headaches from its use.
Cook states that Valerian acts upon the nervous system, “…first the peripheries,” where is acts as antispasmodic in cases of irritability and restlessness, followed by an effect upon the central nervous system, “…inducing quietude and sleep”. Valerian is specific to states of nervous depression. In the treatment of spasm Valerian acts as a mildly relaxing agent, to pacify chronic states of muscular irritability and prevent convulsion, rather than treat seizures once they have occurred. Its action upon the nervous system is best obtained when circulation of the center is inactive and feeble, especially when there is paleness of the face and the skin is cool. It is directly indicated in hysteriacal conditions of whatever character with feebleness; which nervous excitement, and morbid vigilance, in kysterical epilepsy and nervous disturbances incident to menopause. Its general soothing effect in all these cases is desirable. Valerian is also indicated in migraine headaches, where the pain is relieved by warmth on the back of the neck, indicating a cerebral anemia rather than a sthenic, irritable condition. Thus Valerian may also be helpful for the headaches and back pain associated with premenstrual syndrome.