Catha edulis, known as Khat, is a flowering evergreen shrub or small tree. Indigenous to the Horn of Africa and the Arabian Peninsula, its fresh leaves and young shoots have been chewed for centuries. Traditionally, it is used in social gatherings and religious ceremonies.
Botanical Profile and Traditional Use
Catha edulis grows as a shrub, typically 1 to 5 meters tall, but can reach 20 meters as a tree. Its leaves are evergreen, glossy, and ovate, usually appearing in pairs along the stems. The plant thrives in arid to semi-arid climates, often cultivated on terraced mountainsides and in high-altitude regions.
Chewing fresh Khat leaves has been a customary social activity for centuries in countries like Yemen, Ethiopia, Somalia, and Kenya. This practice is often compared to the social consumption of coffee or tobacco in other cultures. Users gather to chew the leaves slowly, allowing the active compounds to be absorbed through the mucous membranes of the mouth. Chewing Khat occurs during social events, business meetings, and religious observances, acting as a social lubricant and stimulant for conversation.
Psychoactive Effects and Active Compounds
Chewing Catha edulis leaves induces immediate physiological and psychological effects. Users report heightened alertness, increased energy, and mild euphoria, often with suppressed appetite and reduced fatigue. These effects typically begin within 15 to 30 minutes of chewing and can last for several hours, depending on the quantity consumed and the potency of the leaves.
The primary psychoactive compounds responsible for these effects are cathinone and cathine. Cathinone is structurally similar to amphetamine and is the more potent stimulant, primarily found in fresh Khat leaves. As the leaves age, cathinone degrades into cathine, a less potent stimulant. These compounds exert their effects by influencing neurotransmitter systems in the brain. Cathinone increases the release and inhibits the reuptake of dopamine and norepinephrine in the brain. This surge in neurotransmitters results in stimulant and mood-elevating sensations.
Health Implications
Catha edulis consumption is associated with adverse health effects, both short and long term. Immediately after use, individuals may experience elevated blood pressure and increased heart rate, risking those with pre-existing cardiovascular conditions. Gastrointestinal disturbances are also common, including constipation, indigestion, and loss of appetite. Prolonged chewing can lead to dental problems, including gum disease, tooth decay, and greenish-brown teeth staining.
Chronic Khat use can result in serious health complications. Liver damage, though less common, has been reported in heavy users. Psychological effects include insomnia, anxiety, and irritability. In susceptible individuals, prolonged high-dose use can precipitate psychotic episodes or exacerbate existing mental health disorders. There is also potential for dependence and addiction, with withdrawal symptoms like lethargy, mild depression, and tremors when use is discontinued.
Global Legal Status and Regulation
The legal status of Catha edulis varies globally, reflecting diverse cultural attitudes and perceived health risks. In traditional growing regions like Yemen and parts of East Africa, Khat cultivation and consumption are largely legal and embedded in social customs. This contrasts with its status in many Western nations.
In the United States, cathinone, Khat’s primary active compound, is classified as a Schedule I controlled substance under the Controlled Substances Act, making possession and distribution illegal. Similarly, the United Kingdom reclassified Khat as a Class C drug under the Misuse of Drugs Act 1971 in 2014, making its supply and possession unlawful. Numerous other countries, including most of Europe, Canada, and Australia, have also implemented bans or strict controls on Khat, often citing public health concerns and the potential for abuse.