Neem seed oil is a natural oil extracted from the seeds of the neem tree (Azadirachta indica), native to the Indian subcontinent. Insect Repellent: Neem seed oil is effective against mosquitoes, fleas, ticks, and other insects due to its strong smell and properties that deter insects. It has been traditionally used to treat skin infections, acne, and wounds due to its antibacterial and antifungal properties.