Investigations used to monitor the possibility of clozapine related side effects such as myocarditis are also performed including baseline troponin, CRP and BNP and for neuroleptic malignant syndrome CK.The dose of clozapine is initially low and gradually increased over a number of weeks. Initial doses may range from 6.5 to 12.5 mg/d increasing stepwise typically to doses in the range of 250–350 mg per day at which point an assessment of response will be performed. In the UK the average clozapine dose is 450 mg/d. But response is highly variable and some patients respond at much lower doses and vice versa. Monitoring
During the initial dose titration phase the following are typically monitored; usually daily at first; pulse, blood pressure and since orthostatic hypotension can be problematic this should be monitored both sitting and standing. If there is a significant drop then the rate of the dose increase may be slowed, temperature.Weekly tests include; Mandatory full blood counts are performed weekly for the first 18 weeks. In some services there will also be monitoring of markers that might indicate myocarditis; troponin, CRP and BNP although the exact tests and frequency vary between services. Weight is usually measured weekly. Thereon other investigations and monitoring will always include full blood counts (fortnightly for 1 year then monthly). Weight, waist circumference, lipids and glucose or HbA1c may also be monitored. Clozapine Response and Treatment Optimisation
As with other antipsychotics, and in contrast to received wisdom, responses to clozapine are typically seen soon after initiation and often within the first week.
In the television series Last Man On Earth (2015) the character Melissa has a psychotic episode and returns home and starts acting how she did pre-pandemic. Her boyfriend Todd sees her take a medication in the morning and asks her what it is. All she will say is "Santas Penis". Todd searches medication books and finds clozapine = Clause a peen. References
Further reading
External links
"Clozapine". Drug Information Portal. U.S. National Library of Medicine. "Clozapine Risk Evaluation and Mitigation Strategy (REMS) requirements will change on November 15, 2021". U.S. Food and Drug Administration (FDA). 29 July 2021. "Clozapine REMS Modification Frequently Asked Questions". U.S. Food and Drug Administration (FDA). 29 July 2021.