Clozapine in brief

Clozapine is an atypical antipsychotic –treatment of schizophrenia in
○ other agents cannot be tolerated- for e.g untreatable adverse reactions 
○ treatment resistant patients
 psychosis in Parkinson’s disease- where standard treatment has failed

Mechanism of action –Works as antagonist across several receptors
 serotonin dopamine cholinergic muscarinic adrenergic histamine H1 weak D2 blocking activity

Common side effects include
 constipation weight gain hypersalivation malaise speech disorders urinary incontinence drowsiness/ sedation dizziness tachycardia

Agranulocytosis , neutropenia and potentially fatal agranuolcytosis reported. Leucocyte and differential WCC before starting FBC every week for 18 weeks Every 2 weeks after that Once stable for 1 year every 4 weeks

Seizures at high doses Cardiovascular and respiratory effects include
○ myocarditis
○ orthostatic hypotension
○ respiratory/ cardiac arrest particularly when administered with benzodiazepines or other psyhcotropic drugs Selective immunoglobulin M immunodeficiency

References

1. British National Formulary ( BNF )
2. Medicine compendium
3. A Pocket Guide to Atypical Antipsychotics by Stephen M Stahl
4. Effect of clozapine on immunoglobulin M plasma levels Roberto Lozano et al Ther Adv Psychopharmacol. 2016 Feb ;6 (1) ;58-60fever