HISTORICAL AND PHARMACOLOGICAL REVIEW ON A UNANI DRUG OF MINERAL ORIGIN: NUQRA (SILVER)

Nuqra (Silver) is one of the precious metals used medicinally for a long time. It is soft, ductile and white coloured metal having resistance to corrosion. Mexico is the world leader in silver production. In India it is obtained in Rajasthan and Karnataka. Owing to sterilization property, the Persian kings used silver vessels to store and transport the drinking water.Nuqrapossesses a cold and dry temperament. Nuqra is medicinally used in three forms: Warq (Leaves), Kushta (calx) and in liquid form (Nuqra sayyal/Ma ul Fizza). Its preparations are used for the treatment of cardiac ailments like Khafqan (palpitation), weakness of vital organs, premature ejaculation, increased nocturnal emission, attenuated semen and decreased libido, insanity, Melancholia and obsession. Purification of silver is recommended before its medicinal use. Long term exposure to silver may cause toxic effects; turning the colour of skin and other body tissues to gray or blue-gray (argyria). In a recent clinical trial Warq Nuqra (silver leaves) exhibited to have hypolipidemic, hypoglycemic, hepatoprotective and cardioprotective effects. Other studies have confirmed antiviral, antifungal, antibacterial, analgesic, antiinflammatory and hypnotic activity of silver. Nano silver particles (AgNPs) are a recent trend as bioenhancer (to enhance the activity) for other drugs. Present review will be helpful for researchers for further research on Nuqraand its preparations. 

Key words: Nuqra, Silver, Unani Medicine, Kushta Nuqra, Warq Nuqra, Fizza