Khat, also known as qat, is a flowering plant native to eastern and southern Africa and the Arabian Peninsula. It is a slow-growing shrub or tree that can reach heights of up to 10 meters in equatorial areas. Khat contains the alkaloids cathinone and cathine, which are stimulants that cause greater sociability, excitement, loss of appetite, and mild euphoria. The fresh leaves and tops of the plant are chewed or, less frequently, dried and consumed as tea to achieve a state of euphoria and stimulation. Khat is part of some social traditions in parts of the Middle East, such as Saudi Arabia and Yemen, and in Eastern Africa, such as Somalia.

Khat is a controlled substance in some countries, including Canada, where it is listed as a Schedule IV drug under the Controlled Drugs and Substances Act. Possession of khat for personal use is not an arraignable offence in Canada, but the maximum punishment for trafficking or possession with the intent of trafficking is ten years in prison. Khat is also listed as a Schedule 2 dangerous drug in Queensland, in the same category as cannabis. In the United States, khat is a Schedule I drug under the Controlled Substances Act.

Khat can cause many side effects, including mood changes, hyperactivity, aggressiveness, anxiety, depression, high blood pressure, manic behavior, paranoia, and psychosis. Severe side effects from khat include migraine, bleeding in the brain, heart attack, changes to blood vessels, lung problems, liver damage, and changes in sex drive and sexual performance. Chronic khat abuse can result in violence and suicidal depression. Khat can make a user psychologically dependent, with cravings and a desire to keep using in spite of potential harm.