Neem (Azadirachta indica): prehistory to contemporary medicinal uses to humankind.

The divine tree neem (Azadirachta indica) is mainly cultivated in the Indian subcontinent. Neem has been used extensively by humankind to treat various ailments before the availability of written records which recorded the beginning of history. The world health organization estimates that 80% of the population living in the developing countries relies exclusively on traditional medicine for their primary health care. More than half of the world's population still relies entirely on plants for medicines, and plants supply the active ingredients of most traditional medical products. The review shows the neem has been used by humankind to treat various ailments from prehistory to contemporary.