<unk>  is an opioid antagonist that is FDA approved for the treatment of known or suspected opioid overdose, as manifested by respiratory and/or central nervous system depression.   Common adverse reactions include hypotension, hypertension, ventricular tachycardia, ventricular fibrillation, dyspnea, pulmonary edema, cardiac arrest, death, coma, and encephalopathy.
Naloxone
Esketamine
Phenazocine
Pentazocine
Flumazenil
Nalorphine
Ephedrine
Alfentanil