Use of cannabinoids in the treatment of schizophrenia

Shizofrenija je dugotrajna psihijatrijska bolest s heterogenom genetskom i neurobiološkom pozadinom te se prezentira kao kombinacija različitih simptoma – pozitivnih (halucinacije i deluzije), negativnih (odsustvo volje i motivacije) te kognitivnih (smetnje pažnje i apstraktnog mišljenja). U mehanizamu nastanka bolesti karakteristična je hiperaktivnost dopaminergičkog sustava u mezolimbičkom putu te disfunkcija glutamatergičkih i gabaergičkih puteva. Trenutačno je glavni način liječenja uporaba antipsihotika koji blokiraju transmisiju preko dopaminskog receptora. Unatoč njihovoj učinkovitosti u liječenju pozitivnih simptoma, negativni i kognitivni simptomi i dalje predstavljaju terapijski izazov. Također su povezani sa nizom značajnih nuspojava što vodi slaboj suradljivosti pacijenata. Prema tome, neophodni su inovativni pristupi i istraživanje novih metoda liječenja. Dokazi studija na životinjama ukazuju na moguću uporabu specifične komponente marihuane (Cannabis sativa) – kanabidiola (CBD), koji nema psihoaktivno djelovanje poput glavne sastavnice tertrahidrokanabinola (THC), a pokazao se kao protektivan čimbenik kod razvoja psihoze. Rezultati istraživanja sa zdravim dobrovoljcima, nekoliko prikaza slučaja bolesnika te istraživanja kliničke populacije ukazuju na relativno dobru podnošljivost kanabidiola u dozama do 1500 mg/dan. S druge strane, antipsihotični učinak je vidljiv tek u jednoj studiji te kliničkom prikazu. Stoga se može zaključiti da zasad nema dovoljno istraživanja koja potkrepljuju uporabu CBD-a u liječenju shizofrenije.Schizophrenia is a long-term psychiatric disorder with a heterogeneous genetic and neurobiological background and is expressed as a combination of different symptoms – positive (hallucinations, delusions), negative (lack of will and motivation) and cognitive symptoms (attention and abstract thinking disturbance). Schizophrenia is associated with hyperdopaminergic activity in the mesolimbic pathway and with disturbances in glutamatergic and GABAergic pathways. Currently, the main treatment for schizophrenia involves the use of antipsychotic medications that block DA receptor transmission. Although they are effective in treatment of positive symptoms, negative and cognitive symptoms still represent therapeutic challenge. Also, these medications produce serious side effects leading to poor compliance. Therefore, innovative approaches and investigation of new methods of treatment are required. Emerging evidence from animal studies points to the involvement of a specific non-psychoactive component of marijuana (Cannabis sativa plant) called cannabidiol (CBD), which is suggestet as a protective factor in the development of psychosis. Results of studies on healthy volunteers, several patient case reports and clinical studies indicate that cannabidiol is relatively well toletared in doses up to 1500 mg/day. On the other side, antipsychotic effect is shown only in one study and clinical report. Therefore, we can conclude that there is no enough studies that could support the use of CBD in the treatment of schizophrenia