Imipramine poisoning

Mannitol (OsmitroL others) [Osmotic Diuretic] Uses Cerebral edema, T lOP/ICP, renal impair, poisonings Action Osmotic diuretic Dose Test dose 0.2 g/kg/dose IV over 3-5 min if no diuresis w/in 2 h, D/C Oliguria 50-100 g IV over 90 min T lOP 0.5-2 g/kg IV over 30 min Cerebral edema 0.25-1.5 g/kg/dose IV >30 min Caution [C, ] w/ CHF or volume overload Contra Anuria, dehydration, HE, PE Disp Inj SE May exacerbate CHF, N/V/D Interactions t Effects OF cardiac glycosides X effects OF barbiturates, imipramine, Li, salicylates EMS Monitor ECG for hypo-/hyperkalemia (T wave changes) OD May cause dehydration, t urine frequency/amount hypotension and CV collapse symptomatic and supportive... 

When a dmg is in its unionised form it will more readily diffuse from the urine to the blood. In an acidic urine, acidic drugs will diffuse back into the blood from the urine. Acidic compounds such as nitrofurantoin are excreted faster when the urinary pH is alkaline. Amfetamine, imipramine and amitriptyline are excreted more rapidly in acidic urine. The control of urinary pH in studies of pharmacokinetics is thus vital. It is difficult, however, to find compounds to use by the oral route for deliberate adjustment of urinary pH. Sodium bicarbonate and ammonium chloride may be used but are unpalatable. Intravenous administration of acidifying salt solutions presents one approach, especially for the forced diuresis of basic dmgs in cases of poisoning. 

Physostigmine sulfate and physostigmine salicylate (Antilirium) are cholinesterase inhibitors that are indicated as antidotes to poisoning from substances possessing anticholinergic properties such as imipramine, a tricyclic antidepressant. In addition, it has been used in open-angle glaucoma. 

Toxic Effects of Acute Overdoses Acute poisoning with tricyclic antidepressants or MAO inhibitors is potentially hfe-threatening. Fatalities are much less common since modern antidepressants have widely replaced these drugs however, suicide rates have not declined consistently as clinical usage of modern antidepressants has increased. Deaths have been reported with acute doses of 2 g of imipramine, and severe intoxication can be expected at doses >1 g, or about a week s supply. If a patient is severely depressed, potentially suicidal, impulsive, or has a history of substance abuse, prescribing a relatively safe antidepressant agent with close clinical follow-up is appropriate. If a potentially lethal agent is prescribed, it is best dispensed in small, sublethal quantities, with the risk that sustained adherence to recommended treatment may be compromised. 

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