Amaltas is a tree which is available with small or medium size. The botanical name of Amaltas is Cassia fistula. This tree is generally evergreen and it grows up to a height of 24 meters. It is believed that Sonali tree, as it is called in Bengali, is a native to southeastern parts of Asia. But today, this plant is widely distributed in the tropics where it is mainly cultivated for decorative purposes. Found generally in all parts of India, it is cultivated in mixed deciduous forests and certain hilly tracts having an altitude of 1200 meters in the outer Himalayan region. This tree is also commonly found in the central and southern parts of India and in the Gangetic valley. In English this Indian medicinal plant is known as golden shower; in Hindi, it is referred to as amaltas; in Sanskrit as aragvadha; in Tamil, it is known as arakkuvadam and so on.

Amaltas tree possesses grey coloured smooth barks spreading out in some small, woody scales up to a thickness of 1.5 centimeter. The leaves of this tree is paripinnate, usually 20 to 40 centimeter in length, petioles and rachis are glandless, leaflets are 3 to 8 pairs, markedly stalked, 5 to 15 centimeter in length and 3.5 to 9 centimeter in width, ovate or oblong, peak acute, base acute to wedgeshaped, dressed with silvery pubescence during the younger period. The flowers of Amaltas are bright yellow in colour, in axillary, pendulous, many-flowered lax racemes of 10 to 40 centimeters in length; five sepals, pubescent, green, ovate or oblong-obtuse; five free corolla, short-clawed, subequal and reddish-veined petals. The fruits of this tree are black or dark brown in colour, having a pendulous or cylindrical shape and it is usually 25 to 30 centimeter long. The diameter of the fruit or pod is 1.5 to 3 centimeter in diameter. The seeds of Amaltas are smooth, flat, small, light brown in colour. There are around 40 to 100 seeds in a pod or fruit, set in a sweetish black pulp. Flowers in this tree bloom from the months of April till October and the fruits of this tree are ripe from the months of December till April as per the local environment.

The dried pulp and pods of Amaltas are considered precious for their laxative properties. The bark and pods demonstrate antiviral activity. The extraction of the pods is prescribed for common fever and pneumonia. Swelled neck as a result of severe cold can be treated by applying heated pods. The pulp is regarded as a safe purgative, highly recommended for children and pregnant women to relieve liver upsets and biliousness. The same is also used externally for the treatment of rheumatism and gout, and it may also be safely used as an analgesic. It is also used for the treatment of black water fever, malaria, leprosy, diabetes and also for the remotion of abdominal obstructions. The slightly sweet seeds of Garmalo, the name of Amaltas in Gujarati, contain carminative, laxative, cooling and antipyretic properties. The seeds are used to give relief from constipation and for the treatment of jaundice, skin diseases, biliousness and swollen throat. Intestinal amoebi-asis is cleared by the use of the powdered whole seeds of Amaltas. The bark of this tree possesses tonic and antidysenteric properties, and as per records, the barks are eaten raw for the treatment of stomachache. In Ayurvedic medicine, it is used for the treatment of diseases of the skin like leucoderma and eczema. The extraction or powder of the bark of Chimkani, the name of the tree in Marathi, is prescribed for treating leprosy, jaundice, syphilis and heart disease. The powdered wood is reportedly used for dysentery, and its ash is used as a caustic to promote healing of open abscesses.

The leaves possess laxative and antiperiodic, and are used in the treatment of jaundice, piles, rheumatism, and externally for skin eruptions, ulcers, wounds, ringworm, eczema, prurigo and pruritis. However, a paste of the fresh leaves is used internally by central Orissa tribal women to cure amenorrhoea. A plaster of the leaves is used for the treatment of chilblains. The bark and leaves are finely mixed with oil and applied to pustules, to reduce swellings in facial paralysis and insect bites. The juice of the leaf is taken internally for the treatment of ring worm and paralysis. The root bark and roots of Amaltas contain astringent, febrifugal, tonic and purgative properties. The roots of this tree is also used in the treatment of biliousness, cardiac disorders, rheumatic conditions, haemorrhages, wounds, boils and ulcers, tubercular glands and a number of other skin diseases. The root, minced along with Cryptolepis buchanani (Asclepiadaceae), is used as an antinarcotic to revitalize the nervous system paralysed due to intoxication of alcohol among the tribals of southern parts of Bihar. In the north-eastern parts of the state of Karnataka, the roots of Amaltas mixed with goat milk are given in little doses regularly for the treatment of breast diseases. The aqueous extract of the bark of the root shows anti-inflammatory activity. The edible flowers of this tree possess astringent, febrifugal, purgative and antibilious properties. For stomach ailments, decoction of the Amaltas flower is generally prescribed.