Neem - western medicine

Because of the historical interest in the many uses for neem, including its use in traditional medicine and pesticides, it has attracted the attention of scientists throughout the world. Despite this research it is still unclear as to which compounds in the plant are responsible for these properties.

Active compounds

Photo of a box of neem toothpaste.
Neem toothpaste.

One group of compounds in neem are called limonoids. They have a range of biological activities. For example, a limonoid called nimbin has anti-microbial activity and reduces fevers. The extracts from neem often have a pungent smell similar to garlic. This is because they contain sulphurous compounds. The sulphur smell of some extracts can be overpowering and has often limited the commercial development of products containing neem. Extraction techniques have been developed that remove these pungent compounds without loss of activity. In the future, the sale of neem-based products for use in cosmetics and hair tonics will become more acceptable for sale to western markets.


There are some reports of allergic reactions to neem products. This could be because another species called Melia azedarach or chinaberry, is also called neem and could have been used in medicinal prescriptions instead of Azadirachta indica. Melia azedarach contains compounds that are thought to be more toxic than those in Azadirachtin indica. This use of the common name 'neem' to describe two different species of plants can be confusing.

This information is provided for general interest only. It is not intended as guidance for medicinal use. Further information on using herbal medicines is available.