Piper longum Linn (Piperaceae) used in  Ayurvedic medicines helps cure leprosy. 

Habit and Habitat A climber occurring in the hotter parts of India, from Central Himalayas to Assam, Khasi and Mikir hills, lower hills of Bengal, and evergreen forests of western ghats from Konkan to Travancore:  and also from Car Nicobar Islands.<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

Uses:  The fruits as well as the roots are attributed with numerous medicinal uses, and may be used for diseases of respiratory tract, viz. cough, bronchitis, asthma, etc.; as counter-irritant and analgesic when applied locally for muscular pains and inflammation; as snuff in coma and drowsiness and internally as carminative; as sedative in insomnia and epilepsy; as general tonic and haematinic; as cholagogue in obstruction of bile duct and gall bladder; as an emmenagogue and abortifacient; and for miscellaneous purposes as anthelmintic, and in dysentery and leprosy.

    Indian Long pepper forms one of the ingredients of Ayurvedic    drug `Trikatu' whose constituents and piperin (a major alkaloid of    peppers) are reported to possess bioavailability enhancing activity    which increases the efficacy of the co-administered Ayurvedic    formulations or medicaments. It also forms the ingredient of    Ayurvedic drugs `Mrtyunjayarasavati' used for chronic sinusitis and    `Anand Bhairava Ras', used for the treatment of amoebiasis

 Besides fruits, the roots and thicker parts of stem are cut and dried and used as an important drug (Piplamul) in the Ayurvedic and Unani systems.

Similar crude drugs (1)P. peepuloides, (2)  P. retrofractum.

Alkaloid A showed significant in vitro antitubercular activity against Mycobacterium tuberculosis H-37 Rv strain; it     inhibited the growth of the bacillus in 20µg./ml. concentrations.      Alcoholic extracts of the dry fruits and aqueous extracts of the         leaves showed activity against Micrococcus pyogenes var. aureus and Escherichia coli. Ether extract of the fruits showed larvicidal properties. 
   

 The fruits are used as spice and also in pickles and preserves. They have a pungent pepper-like taste and produce salivation and numbness of the mouth.    

    In Chota Nagpur the root is used to ferment rice beer. In <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />Andaman Islands, the leaves are chewed like betel leaves.

    There are three grades of Piplamul, Grade I with thick roots and underground stems fetching higher price than Grade II or III, which comprise either thin roots, stems or broken fragments. Commercial drug consists almost entirely of transversely cut pieces (length, 5-25 mm.; diam., 2-7 mm.) which are cylindrical, straight or slightly curved, and some with distinct, swollen internodes showing a number of leaf and rootlet scars. The surface of the pieces is dirty, light brown in colour. The drug has a peculiar odour and a pungent bitter taste producing numbness on the tongue. It contains piperine (0.15-0.18%), piplartine (0.13-0.20%), and traces of a yellow crystalline pungent .    alkaloid (m.p. 116-17°). Other constituents found in the drug include triacontane, dihydrostigmasterol, an unidentified steroid (m.p. 122-