Morphine overdose/toxicity

Respiratory depression, miosis, hypotension, and coma are signs of morphine overdose. While the IV administration of naloxone reverses the toxic effects of morphine, naloxone has a short duration of action and must be administered repeatedly at 30- to 45minute intervals until morphine is cleared from the body. 

The overdose toxicity occurs when the high dose of drug is required for the specific treatment or the drug is taken accidentally or with the intention of suicide. The effects are predictable and dose related. For example delirium by the use of atropine and respiratory failure by morphine occur due to their overdoses. The well known antitubercular drug, streptomycin causes vestibular damage and deafness on prolonged use. 

CR/ER/SR tablets/capsules Swallow whole do not break, chew, crush, or dissolve because of the risk of acute overdose. Ingesting chewed or crushed beads or pellets will lead to the rapid release and absorption of a potentially toxic dose of morphine. 

Symptoms of overdose with meperidine are qualitatively different from those of morphine in that seizures rather than sedation are common. Respiratory depression and miosis are present. While naloxone reverses overdose-associated toxicity, its use in patients who have received large, frequent doses of meperidine may precipitate seizures. 

The most commonly used emetics are ipecac and apo-morphine. Induced emesis is the preferred means of emptying the stomach in awake patients who have ingested a toxic substance or have recently taken a drug overdose. Emesis should not be induced if the patient has central nervous system depression or has ingested certain volatile hydrocarbons and caustic substances. 

In both cases, the blood metamfetamine concentration was less than the lethal concentration of 4.5 pg/ml. Morphine concentrations were higher than the non-toxic concentration of 0.3 pg/ml. It is unlikely that morphine was the cause of death, because it would have caused hypothermia instead of hyperthermia. It is more likely that morphine interacted with metamfetamine, increasing the hyperthermic effect that is typical of metamfetamine overdose. This would explain why hyperthermia caused death, despite a non-lethal blood concentration of metamfetamine. 

The toxic effects due to codeine are similar bnt less toxic than those of morphine and other opium alkaloids. An overdose can cause respiratory failure. It is a weak depressant of the central nervons system. It also exhibits stimnlant action. Toxic symptoms from high dosages may inclnde drowsiness, sleep, tremors, excitement, and hallucinations. It may also produce gastric pains and constipation. An oral LD50 valne in... 

Hydromorphone is easily available and titrateable, inexpensive (except extended release), and well tolerated. It causes less pruritus than morphine. It is equivocal whether it causes less nausea in cases where substantial doses are administered. Hydromorphone can be used in a multimodal approach to treat both acute and chronic pain. It carries less risk of toxic metabolites when compared to morphine and meperidine in patients with renal disease. Overdoses are readily treated with the antagonist naloxone. 

Acute overdose of morphine is manifested by respiratory depression, sonmolence progressing to stupor or coma, skeletal muscle flaccidity, cold and clammy skin, constricted pupils, and, sometimes, pulmonary edema, bradycardia, hypotensiorr, and death. Marked mydriasis rather than rttiosis may be seen because of severe hypoxia in overdose situations (Thomson Healthcare, Inc. 2006). Morphine leads to death in amoimts of 0.15 to 0.2 g (subcutaneous) or 0.3 to 0.4 g (oral) in adults. Babies and yoimg children are much more susceptible and death has been observed at doses of 30 mg (Harvey, 1993). Toxic morphine blood concerrtration is 0.1—1 mg/L, whereas the lethal morphine blood has concentration higher then 4 mg/L (Gossel and Bricker, 1994). 

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