The neem tree, or the Indian margosa tree, is a very common Indian tree which grows in the evergreen dense forests. It is biologically named as Azadirachta indica, which literally means 'free tree of India'. This name has been given to the neem tree by the Persian inhabitants, who were among the first foreign people to know about the hundreds of curative uses of the tree. Apart from India, the neem is also found in Pakistan, Sri Lanka, Myanmar, Japan and in the tropical regions of Australia and Africa.

The most valuable composition of the neem tree is the neem oil, which is extracted from various parts of the tree. It is a bitter oil, and is composed of various bitter alkaloids like nimbin, nimbinin and nimbidin. From the flowers of the neem, a glucoside known as nimbosterin and also a pungent oil known as nimbosterol are obtained. Even the fruits of the neem contain a bitter constituent known as baka yanin. In this manner, all parts of the neem tree - roots, fruits, leaves, flowers and bark - yield the neem oil, which is a very important constituent in Ayurvedic medicine.

The following curative properties are ascribed to the neem tree:-

(i)The neem tree is an air purifier. It can rid the air of harmful microorganisms that cause infections.

(ii)It is a fumigant and a disinfectant.

(iii)The bitter tonic obtained from its root, bark and leaves is used to reduce the excess toxins from the body, which is reduced as ama in Ayurveda. Hence neem oil is used in the treatment of flatulence and indigestion.

(iv)Neem is so bitter that even herbivores do not feed on it. Thus it is used as a pesticide. If grown in the farm with other crops, the neem discharges bitter oils into the ground. This enters the crops and makes them internally fortified. This is a permanent protection for the crops.

(v)Neem also acts as an insecticide.

(vi)Neem helps in the removal of catarrhal matter from the bronchial tubes and thus heals respiratory problems.

(vii)Neem is used in the treatment of several skin problems.

Let us now see how the neem is used in the treatment of several diseases.

(i)Ear Problems

If there is earache, then steam fomentation with neem decoction provides relief. Otherwise, neem leaves can be boiled in a liter of water and the steam obtained is used to foment the ear canal. In case of boils or eruptions in the ear, the juice of neem leaves is mixed with pure honey and taken orally. At the same time, a few drops of the neem juice can be warmed and dropped into the ear repeatedly in a day. Neem oil warmed and put regularly in the ear also helps in reducing hearing problems. Sometimes, insects enter ears, especially in children, and cause infections. When this happens, neem can be used in the following manner: Warm the juice of the neem leaves with some common salt in it. Put a few drops of the juice in the ear to kill the insect and then remove carefully with a pair of tweezers.

(ii)Eye Problems

Neem is used for treatment of eye problems such as night blindness and conjunctivitis. In case of night blindness, apply the juice of the neem to the eyes externally each night. Direct application has better results. This is done by grinding the neem leaves to a fine powder and then making a paste of this with water. Strain this juice through a clean cloth and apply the juice which filters out onto the eyes with an eye rod. In conjunctivitis, apply the neem juice obtained from its leaves directly onto the eyes. It will reduce the pain. This juice must also be applied on the other eye to prevent it from getting infected also.

(iii)Childbirth Problems

When a woman is in labor, the juice of neem leaves is given to the woman. This reduces labor pains. Neem also prevents constipation problems and fevers in pregnant women which may interfere with a normal delivery. Using a warm decoction of the neem as a vaginal douche helps in quick healing of pregnancy-related wounds and eliminates infections.

(iv)Hair Problems

Neem helps in a significant manner in problems related to hair. Neem oil is applied on the scalp, massaging at the hair roots once a day. Instead of neem oil, a decoction of the leaves can also be used. This helps in checking hair loss, fostering their growth and eliminating all parasites from the hair such as lice.

(v)Leprosy

For leprosy, the neem is used in two ways. First, for internal administration, 60 grams of the neem tree sap is given on a daily basis. At the same time, the affected areas are massaged with the same sap regularly. This is continued for forty days. Alternatively, 12 grams of the neem leaves powder with a small pinch of pepper can be taken in water.

(vi)Malaria

An infusion of the leaves of the neem tree is prepared. It is taken in doses of 15 to 60 grams each day. This is a bitter tonic with a stimulating action on the liver.

(vii)Oral Problems

Neem is used in several dental and oral problems. Its twigs are rubbed on the teeth daily. This keeps the teeth whiter and prevents gum problems. Also it helps in tightening the teeth, relieves toothache, treats halitosis and mouth infections.

(viii)Piles

In case of piles, 3 grams of the inner bark of the neem is mixed with double the quantity of jaggery. This mixture is taken every morning before eating anything else. If the piles are complicated into bleeding piles, then eating three or four neem fruits directly with water proves to be very beneficial.

(ix)Smallpox

Perhaps the most use of neem is done in the treatment of smallpox. Its leaves are applied externally on the eruptions. An ointment for external application of smallpox is prepared in the following manner. 50 grams of the leaves are crushed very finely in 50 grams of pure ghee till is becomes as much consistent as an ointment. Otherwise, the bark of the neem is rubbed in water until it forms a paste. Both these are applied on the smallpox eruptions.

Neem does not have any major side-effects on the human body, but it may cause nausea discomfort in some people. If it is taken in a very excessive dose, then there can be moderate to severe problems such as reduced liver metabolism and nervous system problems, including those related with the brain and the spinal cord. If neem oil is brought in contact with the vagina or even taken orally after sexual intercourse, then it could cause an abortion.