A case of brief psychosis upon cannabis withdrawal

Abstract

Psychosis can be a result of mental illness (often seen in cases of schizophrenia for example), stress, or medication side effects. Psychosis can be evident when a patient is taking substances such as Cannabis, however, the psychosis usually resolves when the drug use is discontinued.7 As such, and there are limited cases of psychosis upon withdrawal from Cannabis use described in the literature as it is an infrequent phenomenon. Cannabis contains several cannabinoids with the prominent cannabinoids been cannabidiol and tetrahydrocannabinol (THC).3 Cannabis acts on the cannabinoid receptors (CB1), where it converts to its active form Delta-9tetrahydrocannabinol (THC).7 It subsequently affects intracellular enzymes such as cAMP causing a reduction.7 The decrease in cAMP, then causes a decrease in potassium and calcium channels. As a result, there is a reduction in the amount of neurotransmitter released from axonal terminals, except for dopamine.7 Dopamine is usually inhibited by GABA neurons. Cannabis disinhibits GABA neurons leading to the activation of dopamine.7,8 Excessive dopamine in the mesolimbic tract is hypothesized to cause positive psychotic symptoms.