Treatment of experimental imipramine and desipramine poisoning in the rat

The influence of orally administered activated charcoal on organ concentrations of parenteral imipramine and desipramine was investigated. Ancillary distribution experiments indicated that the gastroenteral cycle of these substances might be more important than the enterohepatic cycle. Nevertheless the effectiveness of repeated activated charcoal dosage in lowering antidepressant concentrations of visceral organs is unpredictable. This is interpreted as a consequence of predominant binding of these drugs in the tissues, in contrast to drugs like acetosal and the barbiturates, which are distributed more evenly in the body water. The conclusion is, that activated charcoal has only limited value as an anitdotal adsorbent in imipramine or desipramine poisoning.

Haemodialysis in imipramine poisoning? An experimental study

In the last several years an increasing number of severe imipramine intoxications have been observed. Though standard principles for the treatment of acute tricyclic poisoning have been established, nonetheless there still exists doubt on the most effective method of tricyclic removal in cases of massive overdose. Haemodialysis was successfully employed until now but has not found general acceptance as only insignificant amounts of imipramine could be recovered from the dialysate. An experimental clearance study was undertaken using radiolabelled imipramine (14C-I) to obtain insight into the usefullness of haemodialysis in imipramine poisoning. 14C-I clearances which were calculated in a closed circuit dialysis system ranged between 18 ml/min and 48 ml/min depending on the constitution of the dialysate, i.e. aqueous or lipid solution. Surprisingly a rapid and significant uptake of imipramine by the plastic material (polyvinylchloride) of the extracorporeal blood line system was detected. This escape of imipramine from the blood into the tubings explains the poor recovery of tricyclics from the dialysate, which discredited haemodialysis as a therapeutical method in imipramine poisoning. The results of our experiments may offer a new method of rapid tricyclic elimination in severe imipramine intoxications.

Amitriptyline and imipramine poisoning in children

The increasing number of children admitted to this hospital with poisoning by tricyclic antidepressants is causing concern. Of 60 children admitted between January 1966 and July 1973, half were admitted in the last 18 months. In 60% of these patients the tricyclic compounds had been prescribed for nocturnal enuresis. One child aged 2 years and 4 months died of imipramine poisoning. It is imperative that all children with poisoning by tricyclic compounds, irrespective of the dosage, are admitted to hospital for continuous cardiac monitoring. Cardiac arrhythmias induced in children by amitriptyline and imipramine are prominent and dangerous.In the earlier years of this survey the antidepressants taken by children had usually been prescribed for adults, but recently they have been increasingly prescribed as a treatment for enuresis in children themselves. Medicine for a trivial complaint is unlikely to be regarded by parents as potentially dangerous and practitioners should therefore warn them accordingly; if, indeed, the transient effect of these potentially dangerous drugs upon the average case of bed-wetting in childhood can be justified.