Charaka has prescribed single Gana of 10 drugs. These are better known as Lekhaniya Gana. The drugs which have a depleting effect on the body are known as Lekhaniya dravya. Chirbilva (Holoptelia intergrifolia) and Hemvati (Iris germanica) are typical examples. These can be compared with anti-obesity drugs. Medohara dravya can better be compared with hypolpidemic agents.
Vata, the biological humors, is responsible for clarity among the channels of circulation, Shoshana of three biological humors and enkindling of the biological fire, Agni. Drugs having katu vipaka (post-digestion effect) are generally said to be lekhaniya because of predominance of Akasha (ether), Vayu (air) and Agni (fire). After the action of Dhatvagni and Bhutagni is over, lekhaniya dravya reduces Kapha, the water humour and coresponding dhatu.
Yava is considered to be having lekhana property, so they are highly useful in obesity. Ayuvedic dietetics recommends use of yava as a dietary solution to obesity. Yava is best lekhana dravya. Owing to these properties, yava helps to stabilize the biological fire, Agni in kostha, cleans the channels of circulation obstructed by Meda dhatu. On account of this, person suffering from voracious appetite in medo roga feels normal hunger. Charaka has indicated guru and aptarpana chikitisa for obesity treatment.
Black piper (Piper nigrum) and Vaca (Acorus calamus) are other examples which remove blockage from channels of circulation ad from Ayurvedic pharmacology point of view, dravya this action are known as Pramathi dravya.
Lekhana Basti has been designed for Apatarpana (emaciation) of the body. In a clinical trial, 19 out of a total of 22 patients completed the course of Lekhana Basti.
Group A was treated with Lekhana Basti and group B was administered the standard control drug, i.e., Triphala Guggulu, for 21 days. In patients treated with Lekhana Basti, serum cholesterol, serum low density lipoprotein and serum apolipoprotein B were decreased by 4.99%, 9.13% and 0.36%, respectively.
A single blinded, controlled study was undertaken to investigate the efficacy of Ooshakadi Lekhana in reducing serum lipids. Ooshaka or Kshara Mrittika (alkaline sand) was used in the study. 45 patients were randomized into three groups, each containing 15 patients. The satin, atrovastatin was used as a control. Average mean reduction of lipids were found statistically significant (p<0.05) in the experimental groups over the control group in all types of lipids except HDL which has presented increase pattern.