^Provides a rough guide only; neither sensitive nor specific
Correct for albumin level
Free<unk>  concentration determines toxicity
Hypoalbuminemia results in higher free<unk>  concentration
Other laboratory testing
LFTs, hepatic dysfunction increases risk of<unk> 
CBC, frequently show eosinophilia or marked leukocytosis
Total CK
ECG, may see arrhythmias, AV block, or sinus arrest with junctional or ventricular escape
POC glucose, rule out hypoglycemia as cause of AMS
Acetaminophen and salicylate levels, rule out common coingestion
Urine pregnancy test
Free<unk>  concentration determines toxicity
Hypoalbuminemia results in higher free<unk>  concentration
LFTs, hepatic dysfunction increases risk of<unk> 
CBC, frequently show eosinophilia or marked leukocytosis
Total CK
ECG, may see arrhythmias, AV block, or sinus arrest with junctional or ventricular escape
POC glucose, rule out hypoglycemia as cause of AMS
Acetaminophen and salicylate levels, rule out common coingestion
Urine pregnancy test
Phenytoin toxicity
Carbamazepine toxicity
Carbamate toxicity
Tianeptine toxicity
Valproic acid toxicity
Antipsychotic toxicity
Mescaline toxicity
Phencyclidine toxicity