Acute physical dependence in the waking dog after a single low dose of morphine

Abstract

SYSNOPSIS: In the waking dog, a small dose of morphine (0·1 mg/kg intravenously) was sufficient (1) to induce a quite appreciable state of sedation which might be more closely related to clinical analgesia than experimental nociception, and (2) to allow for precipitation of clear-cut signs of abstinence (agitation, tachycardia, tachypnoea, mydriasis, hyperthermia, tremors, salivation, urination) when naloxone (3 mg/kg subcutaneously) was injected 1·5 hours later.