Psychopharmacological aspects of catha edulis (khat) and consequences of long term use: a review

Abstract

Catha edulis (khat) is a plant grown commonly in the horn of Africa. Its leaves are chewed by the local people for their stimulant action. The purpose of this review was to summarize the psychopharmacologic aspects of Catha edulis (khat) and consequences of long term use. I collected data from scientific journals. The databases such as Pubmed, Medline, Hinary, Google search, Cochrane, and Embase were searched for literature on the different aspects of Catha edulis (khat) including central nervous system effects, pharmacological effects and long term consequences of khat use. Different research findings from various sources showed that Catha edulis (khat) causes schizophreniform psychotic illness, mania, and more rarely, depression and also has negative impact on health and socio-economic conditions. Most of the effects of chewing khat come from two phenylalkylamines; cathinone and cathine which are structurally related to amphetamine. On occasion these presentations are associated with episodes of self-harm or harm to others. Owing to the mode of consumption, the dose of khat tends to be self-limiting, unlike amphetamines. Therefore toxic psychosis as a result of excessive use is much less frequent with khat than with amphetamines. Frequent khat chewing is responsible for different disorders including psychotic illness and has harmful socioeconomic consequences. It is important for clinicians to increase awareness of their patients and the general public about the harmful effects of khat-chewing.

Keywords

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Catha edulis (gat)’ın psikofarmakolojik yönleri ve uzun dönem kullanımının sonuçları: Bir gözden geçirme

Öz

Catha edulis (gat) Afrika boynuzunda yaygın olarak yetiştirilen bir bitkidir. Yaprakları yerli halk tarafından uyarıcı etkisi sebebi ile çiğnenmektedir. Bu gözden geçirmenin amacı birçok bilimsel makaleden elde edilen bilgiler ışığında gat’ın psikofarmakolojik yönlerini ve uzun dönem kullanımın sonuçlarını özetlemektir. Ben, pek çok bilimsel dergiden veri topladım. Pubmed, Medline, Hinary, Google arama, Cochrane ve EMBASE gibi veritabanlarından Catha edulis (gat)’in merkezi sinir sistemine etkileri, farmakolojik etkisi ve uzun dönem kullanımının sonuçları da dahil olmak üzere farklı yönleriyle ilgili literatür tarandı. Farklı kaynaklardan farklı araştırma sonuçları gat’ın şizofreniform bozukluğa, maniye ve daha az sıklıkla depresyona sebep olduğu ve sağlık ve sosyoekonomik koşullar üzerinde olumsuz etkileri olduğu gösterilmiştir. Gat’ın çiğnenirken ortaya çıkan etkilerinin çoğu yapısal olarak amfetamine benzer olan fenilalkilaminler; katinon ve katinden kaynaklanmaktadır. Bu temsiller hemen her defasında kendine zarar veya diğerlerine zarar ile ilişkilidir. Gatın tüketimde doz amfetaminlere zıt olarak kişiyle sınırlıdır. Bu nedenle gatın aşırı kullanımı sonucu ortaya çıkan toksik psikoz amfetaminden daha az sıklıkla görülür. Gatın fazlaca kullanılması psikotik bozukluk ve sosyoekonomik zararlı sonuçlar gibi değişik bozuklukların ortaya çıkmasında sorumludur. Klinisyenlerin, hastalarının ve genel halkın gat çiğnemenin zararlı etkileri hakkında farkındalığı arttırmaları önemlidir.

Anahtar Kelimeler

• gat, catha edulis, farmakolojik etki, kation, psikolojik sekel, psikoz

Kaynakça

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