Details About Overdose or Poisoning Generic Salt :: Morphine
Drug Pharmacology ::
I. Pharmacology. Morphineis the principal alkaloid of opium and is a potent analgesic andsedative agent. In addition, it decreases venous tone and systemicvascular resistance, resulting in reduced preload and afterload.Morphine is absorbed variably from the GI tract and usually is usedparenterally. After intravenous injection, peak analgesia is attainedwithin 20 minutes and usually lasts 3–5 hours. Morphine is eliminatedby hepatic metabolism, with a serum half-life of about 3 hours;however, the clearance of morphine is slowed and the duration of effectis prolonged in patients with renal failure resulting from accumulationof the active metabolite morphine-6-glucuronide.
Drug Indications ::
Severe pain associated with black widow spider envenomation, rattlesnake envenomation, or other bites or stings.
Pain caused by corrosive injury to the eyes, skin, or GI tract.
Pulmonary edema resulting from congestive heart failure. Chemical-induced noncardiogenic pulmonary edema is not an indication for morphine therapy.
Drug Contra-Indications ::
Known hypersensitivity to morphine.
Respiratoryor CNS depression with impending respiratory failure unless the patientis already intubated or equipment and trained personnel are standing byfor intervention if necessary with intubation or the reversal agentnaloxone (see Naloxone and Nalmefene).
Suspected head injury. Morphine may obscure or cause exaggerated CNS depression.
Drug Adverse Effects ::
IV. Adverse effects
Respiratoryand CNS depression may result in respiratory arrest. Depressant effectsmay be prolonged in patients with liver disease and chronic renalfailure. Risk factors or co-morbidities for morphine-inducedrespiratory depression include naïve user lacking tolerance,hypothyroidism, morbid obesity, and sleep apnea syndrome. Note thattidal volume may be depressed without perceptible changes inrespiratory rate and that these effects are influenced by externalstimuli (eg, noise, manipulation).
Hypotension may occur owing to decreased systemic vascular resistance and venous tone.
Nausea, vomiting, and constipation may occur.
Bradycardia, wheezing, flushing, pruritus, urticaria, and other histamine-like effects may occur.
E. Sulfite preservative in some parenteral preparations may cause hypersensitivity reactions.
F. Use in pregnancy. FDAcategory C (indeterminate). This does not preclude its acute,short-term use in a seriously symptomatic patient (see Table III–1).
Drug Lab Interactions ::
Drug or laboratory interactions
Additivedepressant effects with other opioid agonists, ethanol and othersedative-hypnotic agents, tranquilizers, and antidepressants.
Morphineis physically incompatible with solutions containing a variety ofdrugs, including aminophylline, phenytoin, phenobarbital, and sodiumbicarbonate.
Drug Dose Management ::
Dosage and method of administration
Morphinemay be injected subcutaneously, intramuscularly, or intravenously. Theoral and rectal routes produce erratic absorption and are notrecommended for use in acutely ill patients.
Theusual initial dose is 2–10 mg IV (may dilute with 4-5 mL sterile waterand give slowly over 4–5 minutes as well as titrate in smallincrements, 1–4 mg, every 5 minutes) or 10–15 mg SC or IM, withmaintenance analgesic doses of 5–20 mg every 4 hours. The pediatricdose is 0.1–0.2 mg/kg every 4 hours. Note that the dosage range mayvary and risk factors for respiratory depression should be carefullyconsidered. In particular, exercise caution in morbidly obese patients.Remember that peak analgesic (and toxic) effects may be delayed (by anaverage of 20 minutes for IV), and naloxone should be immediatelyaccessible if respiratory depression occurs.
Drug Chemical Formulations ::
Parenteral. Morphinesulfate for injection; variety of available concentrations from 0.5 to50 mg/mL. Note that some preparations contain sulfites as apreservative.
The suggested minimum stocking level to treat a 70-kg adult for the first 24 hours is 150 mg.