Page 227 - Pharmacognosy 2 PG303
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Pharmacognosy-2 (PG303) Level 2 Clinical Pharmacy-Pharm D
the recent pharmaco-poeial requirement for a minimum oil content. A sharp
distinction must be made between use of the drug (for the preparation of a tea or as
a tincture) and use of the isolated valepotriates, e.g., in prepared medicines which
are employed more as psychostimulants than as sedatives. The pharmacodynamic
effects of a number of the individual constituents have been examined. Thus,
valerenic acid is spasmolytic and muscle relaxant. Valerenic acid and related
sesquiterpenes inhibit the degradation of the important CNS transmitters -amino-
butyric acid. Valerian root tea and tincture are used as a sedative in nervous tension,
restlessness, difficulty in getting to sleep (only to promote sleep, not as a soporific),
and in stress and anxiety states.
On the other hand, the valepotriates or extracts standardized for their
valepotriate contents (usually 50 mg per dose) are used as tranquilizers. Such
preparations, which always contain a mixture of valepotriates, are usually prepared
not from Valeriana officinalis but from other Valeriana species, e.g., V edulis Nutt.
ssp. Procera Meyer (Mexican valerian) or V. wullchii DC. (Indian valerian). They
usually contain fairly large amounts of didrovaltrate and isovaltrate. Such
preparations are employed in the treatment of psychomotor and psychosomatic
problems, loss of concentration and stress and anxiety states.
Adulteration
Experience shows that adulteration of valerian root is not all that rare. With
the whole root, such admixture is generally readily established, but with the cut drug
this is almost always difficult and requires use of the microscope. Often, adulteration
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