Lithium drug overdose

When a 45-year-old man with severe lithium-induced diabetes insipidus developed hyperosmolar, nonketotic hyperglycemia, it was suggested that poorly controlled diabetes mellitus may have contributed to the polyuria (684). Prior contact with a female patient who had developed hyperosmolar coma secondary to lithium-induced diabetes insipidus (685) allowed physicians 4 years later to treat her safely after a drug overdose and a surgical procedure, by avoiding intravenous replacement fluids with a high dextrose content (despite stopping lithium several years earlier, the patient continued to put out 10 liters of urine daily) (686). 

The authors of this report thought that the Brugada syndrome was probably not due to chlorpromazine or lithium in this patient, and it has not been previously described with heroin. It may have been due to hyperkalemia (as the Brugada pattern normalized when the serum potassium concentration normalized), perhaps facilitated by cocaine. Another case of Brugada syndrome is described under Drug overdose . 

When there is no quick and reliable assessment of effect, e.g. lithium for mood disorder To check patient compliance on a drug regimen, when there is failure of therapeutic effect at a dose that is expected to be effective, e.g. antiepilepsy drugs To diagnose and treat drug overdose. 

Serum potassium Myocardial function is critically dependent on serum potassium level. Drugs that cause hyperkalemia include beta-adrenoceptor blockers, digitalis (in suicidal overdose), fiuoride, and lithium. Drugs associated with hypokalemia include barium, beta-adrenoceptor agonists, methylxanthines, most diuretics, and toluene. 

Physical examination revealed tachycardia with irregular heart rate, shallow respiration, decreased bowel sounds, dilated pupils, and hypertheimia. An ECG revealed a widened QRS complex with diffuse T wave changes. If this patient had taken a drug overdose the most likely causative agent was (A) Clozapine Fluoxetine Lithium Thioridazine Zolpidem... 

Drug overdose Treatment of lithium overdose must be individualized to the chnical condition. Three case reports have highlighted the number of options that are available to clinicians. 

Lithium toxicity can occur as a result of intentional overdose therefore, care must be taken when administering lithium to potentially suicidal patients with BPAD. Inadvertent lithium toxicity may also occur. For example, diuretics and nonsteroidal anti-inflammatory drugs such as ibuprofen (Advil, Motrin) slow the excretion of lithium and can lead to accidental toxicity. Consequently, the patient should be advised not to take such commonly available medications while treated with lithium. In addition, dehydration resulting from varied causes such as diarrhea, vomiting, and profuse sweating can lead to accidental lithium toxicity. One should advise the patient who takes lithium to be careful to remain well hydrated at all times and to contact his/her physician if any medical condition arises that may cause rapid fluid losses (e.g., stomach virus, high fevers). 

In a retrospective study of 114 patients admitted to a toxicological ICU with suspected lithium intoxication, 81 had definite intoxication 78% were deliberate overdoses, and 22% were accidental (due, for example, to renal insufficiency, dehydration, drug interactions, poor compliance, drunkenness). Most were treated conservatively with gastric lavage and forced diuresis hemodialysis was used only in 3-6%. Two of those who took a deliberate overdose and one of those who took an accidental overdose died (535). 

Toxicity. Serious medication-related adverse effects associated with actual or potential damage to tissues, organs, or the entire body system. Toxicity may be directly related to critically elevated blood levels of a drug and may be acute (as in tricyclic antidepressant overdose) or chronic (as in prolonged, moderately elevated lithium level). A drug may also produce "toxic effects" at therapeutic doses (such as phenothiazine s potential for inducing bone marrow damage, which in turn causes decreased production of white blood cells). 

Care needs to be taken when combining naproxen with other medications. Known adverse drug interactions can occur with aspirin, methotrexate, ACE inhibitors (for high blood pressure), furosemide, lithium, and warfarin (a blood thinner). An overdose of naproxen may cause dizziness, drowsiness, and gastrointestinal problems. High blood pressure, kidney failure, and coma may occur, but are rare. 

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