| Signs of morphine overdosage include pin-point pupils, depressed respiration, circulatory failure, pulmonary oedema, convulsions, renal failure and coma. Gastric lavage should be performed as soon as possible after ingestion, and intensive supportive therapy carried out. Naloxone may be given as an antidote (initially 0.8 2.0 mg, to a maximum of 10mg, by intravenous injection). Common symptoms of digoxin overdosage are headache, facial pain, fatigue, weakness, dizziness, drowsiness, disorientation, mental confusion, bad dreams and more rarely delirium, acute psychoses, and hallucinations. Visual disturbances including blurred and misted vision may occur. Colour vision may be affected with objects appearing yellow or occasionally green, red, brown, blue or white. Convulsions have been reported.Large doses of squill produce nausea, vomiting and diarrhoea, it has a digitalis-like effect on the heart. Supraventricular or ventricular arrhythmias and defects of conduction may be an early indication of excessive dosage.Treatment of acute digoxin poisoning consists of emptying the stomach by emesis or aspiration and lavage. Activated charcoal may be given. Cardiac toxicity should be treated under ECG control and serum electrolytes should be monitored. Anti-arrhythmic treatment may be necessary and should be determined by the specific arrhythmia present. Atropine may be given intravenously to control bradycardia, and in patients with heart block; cardiac pacing may be necessary if atropine is not effective. Colestyramine or colestipol may be of use in increasing the elimination of cardiac glycosides. | |