Normal Reference Ranges
Adult
15 - 40 mcg/mL
Pediatric
15 - 40 mcg/mL
Clinical Significance
Long-acting barbiturate. Toxicity causes sedation, ataxia, respiratory depression, and hypothermia.
Causes of High
- Phenobarbital toxicity
- Renal or hepatic impairment
Causes of Low
- Subtherapeutic dose
- Non-compliance