Immediate management

Give naloxone ^b intramuscularly 400 microgram followed by400 microgram intravenously ^d 

Why?

A complete response to naloxone makes opiate overdose much more likely

Patient	Target Disorder and Reference Standard	Diagnostic Test	LR+ (95% CI)	Post-test Probability
altered mental state b (pre-test probability: 10%)	opiate overdose (physician review of hospital chart)	complete response to naloxone	28 (12 to 64)	76%
		partial or equivocal response to naloxone	0.74 (0.18 to 2.9)	7.7%
		no response to naloxone	0.19 (0.075 to 0.46)	2.1%