An overdose of such drugs in children may occur accidentally, while in adults it may be voluntary or from therapeutic overdose. By their blocking action on nerve endings, these drugs exert a powerful negative inotropic and chronotropic effect on the heart. The main symptoms are hypotension, convulsion and, in severe cases, coma.
Diagnosis and treatment
Diagnosis is derived from the medical history as laboratory tests are of little help in emergency situations. The stomach can be emptied even many hours after ingestion, and the treatment is directed to clear the body and stimulate the cardiovascular system. If blood pressure does not rise, prenalterol can be administered in a dose of 5-10 milligrams into a vein. As a last resort, application of an intravenous pacemaker may be necessary.
Source: Vadecum of poisoning therapy by Roy Goulding