ARUP's Laboratory Test Directory
| 0098930: Clozapine |
| Test Mnemonic: CLOZAPINE | |
|
Methodology: High Performance Liquid Chromatography
Performed: Mon-Fri Reported: 1-4 days |
| Specimen Required: | |
|
Collect: One 5 mL plain red. Also acceptable: lavender (EDTA), pink (K2EDTA), green (sodium heparin), gray (sodium fluoride/potassium oxalate).
Transport: 1 mL serum or plasma at 2-8°C. (Min: 0.6 mL) Submit specimen in an ARUP Standard Transport Tube. Pediatric Collection/Transport: 0.6 mL serum or plasma at 2-8°C. Remarks: Avoid use of separator tubes and gels. Stability: After separation from cells: Ambient: 5 weeks; Refrigerated: 2 months; Frozen: 2 months |
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| Reference Interval: |
| Therapeutic range not established. |
| Interpretive Data: | |
|
A therapeutic range has not been established; however, a clozapine level of 100 ng/mL is suggested as the minimum therapeutic threshold. Data suggests that concentrations between 200 and 700 ng/mL correlate more with response; however, non-response does occur within this range. For refractory schizophrenia, at least 350 ng/mL of clozapine is suggested to achieve a therapeutic response. After initial therapeutic response occurs, the dose should be progressively reduced to the minimum level necessary to maintain clinical remission. The likelihood of seizures and other side effects increase with clozapine levels greater than 1200 ng/mL and/or dosages greater than 600 mg/d. |
| CPT Code(s): | |
| 80299 |