Boerhavia diffusa, commonly called hog weed, is known as 'erimmirii' (which literally means water-food). Punarnava is found throughout India and Brazil. It is a very important plant for urinary system. It can be white or red and used as a treatment of liver disorders such as jaundice and hepatitis. Throughout the tropics, it is used as a natural remedy for Guinea worms. The plant is used in folkloric medicine to treat convulsions and as a mild laxative and febrifuge (Adesina, 1979). The roots and leaves are considered to have an expectorant action, to be emetic and diuretic in large doses and are used in the treatment of asthma. The thick roots, softened by boiling are applied as a poultice to draw abscesses and to encourage the extraction of guinea worm (Keary and Hepper, 1985).  

Different names of Punarnava are Dirghapatrika, Sitavarsabhu, Visakhah, Sasivatika, Sivatika, Ksudravarsabhuh, Kathillakah, Svetamukha, Prthvika, Dirghapatrakah, Varsabhu, Punarbhau, Svetanwla, Sothaghu, Kathillah, Prthvi, Dirghapatra. Its latin name is Boerhavia diffusa. English name are Spreading Hogweed & Horse Purslane
The fruits known as anthocarps, are 1cm long, round or circular, a club like structure, which gets easily detached from the stalk and gets carried away by animals. The fruit swells in water and becomes slimy. Roots become twisted on drying. It is flowering and fruiting during winter.
Chemical Constituents: Punarnava contains b-Sitosterol, a-2-sitosterol, palmitic acid, ester of b-sitosterol, tetracosanoic, hexacosonoic, stearic, arachidic acid, urosilic acid, Hentriacontane, b- Ecdysone, triacontanol. Punarnavoside (antifibrinolytic glycoside, 0.03-0.05% ) ; Boeravinones, Lignans (liridodendrin, boeravine & hypoxanthine deriv .) ; Flavones, Sterols; Root contains Alanine, Arachidic acid, Aspartic acid, Behenic acid, Boerhavic acid, Boerhavone, Pot.nitrate ( 6.5 % ), Oxalic acid, Punarnavine 1 and 2 etc.
Use of Punarnava
Diuretic property: It is commonly used as diuretic in Ayurvedic texts (mutravirechniya). On administration to nephritic syndrome patient it shows marked improvement in levels of Hemo globin % which may be due to release of erythropoietin from kidney. It has also significant role in reduction in creatinine levels and marginal decrease in blood urea. A rise in serum protein is also reported. Punarnava has maximum activity in samples collected during rainy season. Roots & leaves are more diuretic. Amino acid composition of roots and plant, aspartic and glutamic acids may aid in dissolving calculi of Ca.Oxalate. Diuretic action of the plant may be due to beta ecdosyne. Its Diuretic action is significantly higher in water insoluble alcoholic extract of roots and leaves compared to stem and whole plant.(J.Ind.Med.Assoc., 1955, 25, 19 )
Hepatoprotective property: Its Chloroform and methanol extract exhibit liver enzyme lowering effect. The chloroform extract gives two isolates from which steroidal isolates has significant SGOT lowering property whereas flavones isolates decreases the SGPT enzymes.
Antifibrinolytic property: Punarnavoside & plant extracts are potent antifibrinolytic agents & useful in IUD menorrhagia. It is proved to be an antifibrinolytic agent. This effect was evaluated by the studying the endometrial histology of IUD filtered menstruating monkeys. The effect was seen on menstrual cycle length, duration of menstrual flow, menstrual iron loss & ability of uterine tissue plasminogen activator. Boerhavia diffusa decreases the stromal endometrial edema, inflammation & tortousity of glands & increased deposition of fibrin & platelets in the vessel lumen. Boerhavia diffusa decreases the duration of menstrual flow, menstrual iron loss & activity of uterine tissue plasminogen.
Hypoglycemic activity: The aquous leaf extract of Boerhavia diffusa produces non dose related decrease in blood glucose level in alloxan induced diabetic rats. The non dose response of hypoglycemia has its onset of action in less than 2 hours, peaked at 6 hours & lasts for over 8 hours after oral administration. The mechanism of action was not clearly mentioned but it is assumed that the extract might be stimulating the residual pancreatic cells function or produce the hypoglycemia through an extra pancreatic action, probably increasing peripheral utilization of glucose.
Anti-hypertensive Liridodendrin & Hypoxanthine are active antihypertensive agents & the former is Ca .channel antagonist
Traditional Ayurvedic Uses of Punarnava: This plant is a powerful Rasayana dravya (longevity enhancer). It is very much beneficial for the kidneys, especially the nephron cells which are damaged by long-term hyperglycemia (diabetes) and it pacifies two of the main laws of physiology (Vata and Kapha). Punarnava enhances the quality of bodily tissues, including nutrient plasma (Rasa Dhatu), blood (Rakta Dhatu), muscle (Mamsa Dhatu), fat (Meda Dhatu), bone marrow and nerves (Majja Dhatu), and reproductive fluids (Shukra Dhatu). According to Ayurveda, Punarnava is diuretic by increasing renal blood flow. It is bitter, cooling, astringent to bowels, useful in leucorrhoea, inflammations, asthma etc. The leaves are useful in dyspepsia, tumors, and abdominal pains. According to Unani system of medicine, the leaves are appetizer, alexiteric, useful in joint pains. Seeds are tonic expectorant, carminative, useful in lumbago, scabies. The seeds are considered as promising blood purifier.
Whole herb and roots are commonly used. Each part has a different therapeutic value and must be prepared in its own way for maximum benefits. Powder is used 5-10 gm/day, Juice is used 10-20 ml
Precaution Punarnava must be used cautiously with other diuretics
1. MD (Kaychikitsa), IMS, BHU
2. MD (Rachna Sarir), IMS, BHU
3. Professor,Deptt. of Kaychikitsa, IMS, BHU