Urine pregnancy
CBC, Metabolic panel, LFTs, coags, APAP level, ASA level
Total CK level
ECG
UA
Tox screen, blood alcohol
Serum osmoles, urine Na (if Hyponatremia present)
Head CT as indicated
LP to rule out Meningitis if infectious symptoms and based on history and physical
Urine tox fails to detect unless large doses
More usually positive test for amphetamines
Confirmation must use specialized lab tests (gas chromatography)
More usually positive test for amphetamines
Confirmation must use specialized lab tests (gas chromatography)
Ecstasy 
Cocaine
Amphetamines
Benzocaine
Synthetic cathinones 
Ketamine
Synthetic cannabinoids
Toxic alcohols