More than half of all modern drugs—ranging from aspirin to the newest, most beneficial drug for treating breast cancer—are based on ingredients from plants. Medical practitioners on the Indian subcontinent have produced a wealth of plant-based medical knowledge that is unparalleled in the world. While modern medicine has largely ignored the Ayurvedic medical tradition, recent reviews of the proven efficacy of ancient natural treatments are finally gaining respect throughout the world.
Among the thousands of plants used in Ayurveda, neem, in particular, is generating intense scrutiny as its traditional uses are verified and expanded. Neem is proving to be more than just the “village pharmacy” of our ancient India; it is becoming the “ultimate herb” of today and tomorrow. It has become important in the global context because it offers answers to much number of concerns faced by mankind. One can understand the tremendous international interest in neem by the number of patents filed on the various properties, active principles and their extraction and stabilizing processes, especially in US and Japan. Over 30 patents have already been granted. Now, the issue at the centre of the worldwide debate is that who are going to control the neem’s genetic resources — whether the traditional cultures or trans-national corporations! While this controversy seems to continue for some time, a lot of scientific work is being carried on the neem tree correspondingly.
Bark: Neem bark is cool, bitter, astringent, acrid, and refrigerant. It is useful in tiredness, cough, fever, loss of appetite, and worm infestation. It heals the wounds and is used in vomiting, skin diseases, and excessive thirst. Nimbidin found in the neem bark is now known to be anti-pyretic and non-irritant, and it has found to be effective in treatment of skin diseases such as eczema, furunculosis, arsenical dermatitis, burn ulcers, herpes labialis, scabies and seborrheic dermatitis. It is also effective in the treatment of skin diseases of unknown origin, such as warts and dandruff. Extracts of bark have potent diuretic and anti-inflammatory properties. Nimbidin and sodium nimbidinate contained in neem bark are reported to possess spermicidal activity. Neem bark has shown antibacterial activity against various organisms.
Leaves: According to Ayurveda, neem leaves help in the treatment of vaata disorders (neuromuscular pains). Neem leaves are also reported to remove toxins, purify blood, and prevent damage caused by free radicals in body by neutralizing them. Neem leaves are reported to be beneficial in eye disorders and insect bite poisons. Neem leaves contain nimbin, nimbinine, deacetylnimbinase, nimbandial, nimbolide and quercentin. Studies indicate that tender leaves are effective in parasitic infections. A 10% aqueous extract of tender leaves has been found to possess anti-viral properties. Studies on plasma clotting time using Russell’s viper venom have proved that the leaf extract contains a clotting inhibitor. This justifies its use in the treatment of poisonous bites. A total extract of neem leaves has shown potential as a potent hepatoprotective agent. Water extracts of neem leaves have shown significant anti-ulcer activity. Essential oil from fresh leaves has a mild fungicidal action. Neem leaf extracts have shown reduction in the frequency and severity of stress-induced gastric mucosal lesions. Intraperitoneal administration of neem leaf, bark, and seed extracts revealed immunostimulatory properties of neem, which are responsible for their anti-HIV effect.
Fruits: Neem fruits are bitter, purgative, anti-hemorrhoid and anti-helmintic in nature.
Flowers: Neem flowers are used in vitiated conditions of pitta (balancing of the body heat) and kapha (phlegm formation). They are astringent, anthelmintic and non-toxic.
Seeds: Neem seeds are also described as anthelmintic, antileprotic, anti-poisonous and bitter in taste. Azadirachtins from neem seed kernel are among more than a 100 compounds found in neem. So far, twelve azadirachtins have been identified, all the twelve have high level of biological activity. It has been reported that a single low dose of azadirachtin immunized the kissing bug, a transmitter of Chagas disease. Azadirachtins have shown inhibition of larval, pupal and adult moults and of reproduction and fitness of both plant-feeding and aquatic larvae like mosquitoes. Gedunin contained in whole fruit has been shown to possess anti-malarial activity.
Oil: Neem oil derived from crushing the seeds is antidermatonic, a powerful anthelmintic and is bitter to taste. It has a wide spectrum of action and is highly medicinal in nature.
Mixture: Five parts of neem tree i.e. bark, root, fruits, flowers and leaves are used together in diseases of blood. It is also used in vitiated conditions of excess heat, itching, wound, burning sensation in body and skin diseases.
MEDICINAL USES
• Psoriasis: Neem seed oil and leaf extracts are excellent for psoriasis. It relieves the itching and pain while reducing the scale and redness of the patchy lesions.
• Diabetes: Oral doses of neem leaf extracts reduced insulin requirements by 30 to 50 per cent in nonketonic, insulin-fast and insulin-sensitive diabetics.
• AIDS: Various studies on AIDS report encouraging results in laboratory tests, both preventative and possible cure using neem extracts.
• Cancer: Polysaccharides and limonoids found in neem bark, leaves and seed oil reduce tumors and malignant growths.
• Heart disease: Neem delays the coagulation of blood, calms erratic heartbeats and helps reduce elevated heart rates and blood pressure.
• Herpes: Recent tests in Germany show that neem extracts act against the herpes virus and can quickly heal cold sores.
• Periodontal disease: German and American researchers have proven that neem extracts prevent tooth decay and can prevent and heal periodontal disease.
• Dermatology: Neem is highly effective in treating skin disorders like acne, eczema, itching, dandruff, and warts.
• Allergies: Neem inhibits allergic reactions when applied externally or consumed as a decoction.
• Ulcers: Neem extracts provide significant protection from discomfort and speed up the healing of gastric and duodenal lesions.
• Encephalitis: An outbreak of Japanese encephalitis in India apparently ended when children were dosed twice a day with crushed neem leaves.
• Birth control (men): In India and the United States, trials show neem oil extracts reduced fertility in male monkeys without inhibiting libido or sperm production, making it potentially the first male birth control pill.
• Birth control (women): Used as a vaginal lubricant, neem oil is up to 100 per cent effective in preventing pregnancy.
• Hepatitis: Tests in the U.S. show neem adversely affects the virus that causes hepatitis B.
• Fungi: Neem is toxic to several fungi, which attack humans, including those that cause athlete’s foot and ringworm, and Candida, an organism that causes yeast infections.
• Malaria: An active ingredient in neem leaves, called Irodin A, is toxic to resistant strains of malaria.
• External parasites: Neem quickly kills external parasites and a neem decoction is highly preferable to the standard highly toxic treatments for head lice and scabies.
• Insect repellent: Studies have shown that neem compounds are more effective insect repellents than the widely used synthetic chemicals, which are suspected carcinogens over long periods of use.
• Insecticide: Neem extracts have been approved by the scientific community for use on food crops as insecticides. It is non-toxic to birds, animals, beneficial insects, or man and protects crops.
PLEASE NOTE
Taking neem leaf or bark powder every other day or drinking a mild neem tea will enhance antibody production and the body’s cell-mediated immune response, helping to prevent infections. However, never take neem for more than three weeks without at least one week break.
While neem should be taken internally for diseases of the organs, the immune system, the circulatory system, and other problems inside the body, neem can be used externally and supplemented, if necessary, with oral administration, for diseases affecting the skin. However, neem should not be taken internally for more than two weeks. In severe cases, oral administration may be resumed after one week in a continuing cycle, preferably under the direction of an Ayurvedic physician.
Extensive research has been conducted on neem oil extracts and it has been found to be safe in limited dosage for short periods. Some people taking neem oil internally have experienced nausea and general discomfort, which happens to be the case with many oils containing sulphur compounds. Excessive consumption of raw neem oil has resulted in reduced liver functioning and problems concerning the central nervous system. However, the adverse effects of neem oil consumption in small quantities have been disputed by some researchers. One researcher even showed that small amounts of pure neem oil actually protect the liver from damage.
Neem oil, taken orally or vaginally after intercourse, has been found to possess anti-implantation effects and may also lead to abortion. As the oil is extremely bitter, it is doubtful if anyone would choose to ingest it. However, pregnant women or those trying to conceive should never ingest neem oil and should avoid using it intra-vaginally.
There is no definitive answer regarding the toxicity of ingested neem oil, but caution should be exercised whenever it is taken internally. Darker oil has been found to be more toxic than lighter oil in recent studies. The darker oil is usually made from older seeds that have been contaminated with fungi, and usually produce aflatoxin.
However, the leaves are more or less safe when consumed in small quantities. But neem has many powerful compounds and should not be categorized with milder herbs.
Many Indians, especially from the rural pockets, have grown up with neem in their food, as medicine and for hygiene. Some people eat large amounts of neem leaves and frequently drink neem oil without any apparent ill effect. However, for those who are not familiar with neem, it should be used judiciously until a determination can be made about an individual level of tolerance or intolerance. Whenever any herb or food product produces undesirable effects, it should be avoided or the dosage reduced. This holds true for neem, as with any other substance.