indication

Used in the management of anxiety and in the treatment of muscle spasm.

pharmacology

Chlormezanone is a non-benzodiazepine muscle relaxant. It was discontinued worldwide in 1996 by its manufacturer due to confirmed serious and rare cutaneous reactions (toxic epidermal necrolysis).

mechanism of action

Chlormezanone binds to central benzodiazepine receptors which interact allosterically with GABA receptors. This potentiates the effects of the inhibitory neurotransmitter GABA, increasing the inhibition of the ascending reticular activating system and blocking the cortical and limbic arousal that occurs following stimulation of the reticular pathways.

toxicity

Symptoms of overdose include drowsiness, weakness, nausea, dizziness, abdominal pain, cerebral oedema and renal tubular necrosis, hyperglycaemia and hypoglycaemia, liver damage, encephalopathy, coma and death.