Naloxone

Patients with pre-existing cardiovascular disease face elevated risk of hypertensive crisis, cardiac arrhythmia, and myocardial ischemia from the sympathetic activation associated with naloxone-precipitated opioid withdrawal. Documented in case reports of post-naloxone cardiovascular events.

Known hypersensitivity to naloxone hydrochloride or any component of the formulation is the only absolute contraindication. Anaphylaxis has been reported rarely.

In known or suspected opioid-dependent individuals outside of life-threatening overdose, naloxone administration will precipitate acute withdrawal that is more severe and rapid than spontaneous withdrawal. This is not a contraindication in life-threatening overdose where respiratory arrest outweighs withdrawal risk, but mandates cautious dose titration and post-administration monitoring.