Blood Test Requirements for Psychotropic Medications

Medications Requiring Mandatory Blood Monitoring

The American Academy of Psychiatry recommends baseline testing and regular monitoring for patients taking first-generation antipsychotics, with no routine laboratory monitoring required in alert, cooperative patients with normal vital signs and noncontributory history/physical examination 1, 2, 3
For patients taking first-generation antipsychotics, such as haloperidol or chlorpromazine, blood pressure should be monitored for orthostatic hypotension, especially in elderly patients 4

The American College of Emergency Physicians recommends that elderly patients (≥65 years) undergo targeted laboratory evaluation, including TSH, vitamin B12, urinalysis, and comprehensive metabolic panel 5, 4
Patients with a substance abuse history should undergo comprehensive metabolic panel, glucose, TSH, hepatic panel, and urine toxicology screen 5, 6

The American Academy of Pediatrics recommends against routine urine drug screens, as they have a low yield (5% positive in routine screening) with no management changes in alert, cooperative patients with normal vital signs 7, 1, 2
Extensive laboratory panels (CBC, CMP, LFTs) should be avoided, as false positives are 8 times more common than true positives (1.8%) when history/physical examination are normal 1, 3

The American College of Emergency Physicians recommends that diagnostic evaluation should be directed by history and physical examination, not routine blanket testing 1, 2, 3
Serum glucose should be checked only if hypoglycemia/hyperglycemia is suspected based on history or examination 3
Electrolytes should be ordered when medication use, excessive water intake, or clinical presentation suggests metabolic disturbance 3
CBC should be obtained when infection is suspected based on fever or immunocompromised status 3
TSH should be performed if affective disorder with clinical signs of thyroid disease 1, 3

The American Academy of Emergency Medicine recommends weekly CBC for the first 6 months, then biweekly for months 6-12, then monthly thereafter for patients taking Clozapine 8
History and physical examination have 94% sensitivity for identifying medical conditions requiring testing, and blanket laboratory panels should not be ordered 8

The American Academy of Emergency Medicine suggests that symptom-directed testing should be used, such as ordering CBC for patients with fever or infection signs, and electrolytes for suspected metabolic disturbance 8
The American Academy of Emergency Medicine also recommends against ignoring drug interactions, such as the decrease in levels of risperidone, olanzapine, clozapine, quetiapine, ziprasidone, and haloperidol through enzyme induction by carbamazepine 8