Michelle Muscat MD MRCS(Ed) MSc, PG Dip, FRCPath, PhD

Khat or Catha edulis, also known as ‘miraa’ or ‘qat’, (1) is a plant which provides mild stimulant effects. It is consumed by chewing twigs and leaves. Cathinone and cathine are the main addictive components (2). It is native to Africa as well as the Arabian Peninsula from where exports need to be transported quickly to ensure the psychoactive effect is retained by the time of consumption. In countries where the plant is indigenous, khat is used socially and traditionally amongst communities. It is sometimes used by students when studying for exams (3). Varied beliefs and perceptions (4) surround use of this drug. Some see it as a substance use disorder (5) given abstinence may be difficult after chronic use (6),  dependence has been reported and (7) withdrawal symptoms have been documented (8). Others see it as an innocuous cultural tradition rather than drug abuse (9), although there exists no universal agreement to that effect (10).

Some documented side-effects include insomnia, adverse cardiovascular effects (11), impotence (12), liver disease (13-16), anxiety (17), reduced appetite, increased risky sexual behavior in consumers (18), hypnagogic hallucinations (19),  and decreased pulmonary function  after longer term consumption  (20). There have been associations with oral conditions such as periodontal disease, xerostomia and possibly oral cancer (21, 22). A case report described khat combined with tranylcypromine resulting in subarachnoid hemorrhage (23) There is potential for drug interactions (24).

Khat induced apoptosis in a bovine kidney cell line (25). Experiments showed cytotoxicity of khat on a human breast cancer cell line (26). It has been tried in rats to reduce obesity (27).

At one point there were concerns that some of the profits of khat sales may have been used by terrorist groups (28) although khat farmers have denied this.

These are just some of the current issues associated with khat, future research on khat may help elucidate further the exact risks and potential uses (29, 30).

References

 

 

  1. Patel NB. Khat (Catha edulis Forsk) – And now there are three. Brain research bulletin. 2019;145:92-6.
  2. Sallam MA, Sheikh KA, Baxendale R, Azam MN, Hossain AM, El-Setouhy M. The Physiological and Ergogenic Effects of Khat (Catha edulis Forsk) Extract. Substance use & misuse. 2018;53(1):94-100.
  3. Ayano G, Yohannis K, Abraha M. Epidemiology of khat (Catha edulis) consumption among university students: a meta-analysis. BMC public health. 2019;19(1):150.
  4. Nakajima M, Hoffman R, Alsameai A, Khalil NS, al’Absi M. Development of the Khat Knowledge, Attitudes and Perception Scale. Drug and alcohol review. 2018;37(6):802-9.
  5. Duresso SW, Matthews AJ, Ferguson SG, Bruno R. Using the Severity of Dependence Scale to screen for DSM-5 khat use disorder. Human psychopharmacology. 2018;33(2):e2653.
  6. Duresso SW, Bruno R, Matthews AJ, Ferguson SG. Stopping khat use: Predictors of success in an unaided quit attempt. Drug and alcohol review. 2018;37 Suppl 1:S235-S9.
  7. Gupta S, Dutta ES, Raju M, Kumar A. Leaf it or not: A case of khat dependence from India. Indian journal of psychiatry. 2017;59(1):126-7.
  8. Duresso SW, Bruno R, Matthews AJ, Ferguson SG. Khat withdrawal symptoms among chronic khat users following a quit attempt: An ecological momentary assessment study. Psychology of addictive behaviors : journal of the Society of Psychologists in Addictive Behaviors. 2018;32(3):320-6.
  9. Patel NB. “Natural Amphetamine” Khat: A Cultural Tradition or a Drug of Abuse? International review of neurobiology. 2015;120:235-55.
  10. Odenwald M, Klein A, Warfa N. Introduction to the special issue: the changing use and misuse of khat (Catha edulis)–tradition, trade and tragedy. Journal of ethnopharmacology. 2010;132(3):537-9.
  11. Mega TA, Dabe NE. Khat (Catha Edulis) as a Risk Factor for Cardiovascular Disorders: Systematic Review and Meta-Analysis. The open cardiovascular medicine journal. 2017;11:146-55.
  12. Mwenda JM, Arimi MM, Kyama MC, Langat DK. Effects of khat (Catha edulis) consumption on reproductive functions: a review. East African medical journal. 2003;80(6):318-23.
  13. Orlien SMS, Berhe NB, Morgan MY, Johannessen A. Khat-related liver disease in sub-Saharan Africa: neglected, yet important. The Lancet Global health. 2019;7(3):e310.
  14. Vento S, Dzudzor B, Cainelli F, Tachi K. Khat-related liver disease in sub-Saharan Africa: neglected, yet important – Authors’ reply. The Lancet Global health. 2019;7(3):e311.
  15. Waters M, Oxner A, Krajden S, Sultanian R. Acute Liver Injury Associated with Khat Use in a 24-Year-Old Male. Case reports in hepatology. 2018;2018:2816907.
  16. Orlien SMS, Sandven I, Berhe NB, Ismael NY, Ahmed TA, Stene-Johansen K, et al. Khat chewing increases the risk for developing chronic liver disease: A hospital-based case-control study. Hepatology. 2018;68(1):248-57.
  17. Bahhawi TA, Albasheer OB, Makeen AM, Arishi AM, Hakami OM, Maashi SM, et al. Depression, anxiety, and stress and their association with khat use: a cross-sectional study among Jazan University students, Saudi Arabia. Neuropsychiatric disease and treatment. 2018;14:2755-61.
  18. Ware E, Tura G, Alemu T, Andarge E. Disparities in risky sexual behavior among khat chewer and non- chewer college students in Southern Ethiopia: a comparative cross-sectional study. BMC public health. 2018;18(1):558.
  19. Granek M, Shalev A, Weingarten AM. Khat-induced hypnagogic hallucinations. Acta psychiatrica Scandinavica. 1988;78(4):458-61.
  20. Woldeamanuel GG, Geta TG. Impact of chronic khat (Catha edulis Forsk) chewing on pulmonary function test and oxygen saturation in humans: A comparative study. SAGE open medicine. 2019;7:2050312118824616.
  21. Al-Maweri SA, Warnakulasuriya S, Samran A. Khat (Catha edulis) and its oral health effects: An updated review. Journal of investigative and clinical dentistry. 2018;9(1).
  22. Soufi HE, Kameswaran M, Malatani T. Khat and oral cancer. The Journal of laryngology and otology. 1991;105(8):643-5.
  23. van der Heide D, Merckelbach H, van Harten P. [Tranylcypromine and khat: a potentially fatal combination]. Tijdschrift voor psychiatrie. 2018;60(8):544-7.
  24. Abebe W. Khat: A Substance of Growing Abuse with Adverse Drug Interaction Risks. Journal of the National Medical Association. 2018;110(6):624-34.
  25. Ageely HM, Agag AE, Mohan S, Shehata A. Catha edulis (khat) Induces Apoptosis in Madin-Darby Bovine Kidney Cell Line. Pharmacognosy magazine. 2016;12(Suppl 4):S454-S9.
  26. Lu Y, Li Y, Xiang M, Zhou J, Chen J. Khat promotes human breast cancer MDA-MB-231 cell apoptosis via mitochondria and MAPK-associated pathways. Oncology letters. 2017;14(4):3947-52.
  27. Aziz HA, Peh KK, Tan YT. Herbal delivery system for treatment of obesity administration of encapsulated khat-extracts on body weight of rats. Obesity research & clinical practice. 2011;5(4):e267-360.
  28. Balint EE, Falkay G, Balint GS. [Khat (Catha edulis): is it “coffee” or “cocaine”?]. Orvosi hetilap. 2013;154(27):1055-7.
  29. Al-Motarreb A, Al-Habori M, Broadley KJ. Khat chewing, cardiovascular diseases and other internal medical problems: the current situation and directions for future research. Journal of ethnopharmacology. 2010;132(3):540-8.
  30. Griffiths P, Lopez D, Sedefov R, Gallegos A, Hughes B, Noor A, et al. Khat use and monitoring drug use in Europe: the current situation and issues for the future. Journal of ethnopharmacology. 2010;132(3):578-83.