Morphine overdose

In retrospect, the reason for this is not all that obscure. Most of the soldiers were in hypo-volaemic shock with low blood pressure, low blood volume, and as part of the shock syndrome, systemic circulation was minimal with intense vasoconstriction - hence the poor therapeutic effect. The repeated doses of morphine were usually given intramuscularly into the buttock or thigh but their clearance into the systemic circulation was minimal until resuscitation occurred and the peripheral circulation was restored. Blood flow to the muscle increased and all the morphine injected became available - all at once. This was the reason for the morphine overdoses and the occasional death. Thereafter it has become standard practice to give morphine in emergency directly into the veins and not into poorly perfused muscles. 

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 most common side effect of pentazocine is sedation resulting from an interaction with the K-receptor. Also observed are sweating, dizziness, psychotomimetic effects, anxiety, nightmares, and headache. Nausea and vomiting are less frequent than with morphine. Respiratory depression and increased heart rate, body temperature, and blood pressure accompany overdose. Naloxone is effective in reducing the respiratory depression but requires the use of higher doses than for morphine overdose. 

Morphine depresses all phases of respiration (respiratory rate, tidal volume, and minute volume) when given in subhypnotic and subanalgesic doses (Figure 47.6). In humans, a morphine overdose causes respiratory arrest and death. Therefore, morphine and other narcotic analgesics should be used with extreme caution in patients with asthma, emphysema, and cor pulmonale, and in disorders that may involve hypoxia, such as chest wound, pneumothorax, or bulbar poliomyelitis. 

Action on receptors provides numerous examples. Beneficial interactions are sought in overdose, as with the use of naloxone for morphine overdose (opioid receptor), of atropine for anticholinesterase, i.e. insecticide poisoning (acetylcholine receptor), of isoproterelol (isoprenaline) for overdose with a P-adrenoceptor blocker (p-adrenoceptor), of phentolamine for the monoamine oxidase inhibitor-sympathomimetic interaction (a-adrenoceptor). 

Opiates are used clinically because of their analgesic properties. Opiates also cause sedation, euphoria, respiratory depression, orthostatic hypotension, diminished intestinal motility, nausea, and vomiting. The major manifestations of morphine overdose are coma, miosis (pinpoint pupils), and respiratory depression. Pulmonary edema often is a complication of morphine overdose, and death may result from cardiopulmonary arrest. Treatment for morphine overdose includes administration of the opiate antagonist naloxone (Narcan), which dramatically reverses the effects of morphine. 

The dangerous side-effects of morphine are those of tolerance and dependence, allied with the effects morphine can have on breathing. In fact, the most common cause of death from a morphine overdose is by suffocation. Tolerance and dependence in the one drug are particularly dangerous and lead to severe withdrawal symptoms when the drug is no longer taken. 

Meperidine (Demerol) Also used to treat chills induced by amphotericin B. Like morphine. Overdose causes convulsions due to excitatory actions of metabolite. 

A person ingests a morphine overdose. The half-life of morphine in blood is about 3.0 h. If the blood plasma concentration 5.0 h after ingestion was 6.0 mg dm of blood, estimate the peak concentration of morphine at the time of ingestion. 

Dr S said I listened to the sequence of events as told to me by Dr VM and I thought that the features of her illness were of respiratory problems I had experience of a morphine overdose just two months before in a similar situation. A baby was given 10 times too much but the mistake was spotted almost immediately and nothing happened to the baby. So I did not think 100 times morphine equalled death. I thought we had counteracted the morphine and the problem was respiratory. ... 

Two of these incidents may have contributed to the death of a patient (a 10-fold morphine overdose in a premature, unstable patient and dysfunctional cerebral function monitoring that delayed treatment of seizures). Another five incidents were expected to result in permanent major harm 3-day delay in test results for congenital hypothyroid disorder, defective ventilator resulting in severe metabolic acidosis, arterial line occlusion resulting in foot necrosis, bums due to chlorhexidene, and skin necrosis after subcutaneous infusion of packed cell. 

Age In 86 non-intubated infants, those on morphine experienced respiratory depression (in 12% compared with 0%), and two infants had to be withdrawn because of morphine overdose [141 ]. Morphine should be administered with caution in this population. 

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