Morphine
Class
Analgesic - opium derivative, Schedule II narcotic
Description
1. Has a combination of actions in the C.N.S.; some effects are depressant in
nature and some stimulating.
2. Depresses respiratory, cough and vasomotor center in the medulla.
3. Pain and anxiety are relieved by central effect (binds to opiod receptors)
which raises the pain threshold, and produces euphoria and sedation.
4. Stimulates the vomiting center in the medulla
5. Stimulates the parasympathetic nervous system, which results in decreased
peripheral resistance, increased venous capacitance, venous pooling and
decreased venous return to the heart.
6. Constricts respiratory bronchioles, but has no effect on pulmonary vascular
resistance.
7. May decrease heart rate and myocardial oxygen consumption (parasympathetic
effect).
Onset & Duration
Onset: Acts rapidly when given I.V. with demonstrable effects within seconds to
minutes; peak in 20 minutes.
Duration: lasts 3 - 7 hours.
Indications
1. Drug of choice for the treatment of pain and anxiety associated with an A.M.I.
2. Burns and isolated traumatic injuries.
3. C.H.F. and acute pulmonary edema to relieve anxiety and produce euphoria,
decrease respiratory rate and decrease venous return to the heart.
Contraindications
Systolic BP <100, Hypersensitivity, acute bronchial asthma, multisystems trauma,
acute abdomen, respiratory depression, coma, hypotension, upper airway
obstruction (epiglottitis, laryngeal edema, F.B.A.O. and strider), head injury,
decreased level of conscious hypovolemia, increased intracranial pressure.
Adverse Reactions
CNS: sedation, somnolence, clouded sensorium, confusion, headache, insomnia,
euphoria and seizures with large doses.
CV: tachycardia, asystole, hypertension, syncope, edema, hypotension and
bradycardia.
EENT: meiosis.
GI: nausea, vomiting, dry mouth, biliary spasms, anorexia, constipation and
ileus.
GU: urinary retention or hesitancy.
RESP: respiratory depression, bronchospasm
SKIN: flushing, rashes and pruritus.
OTHER: physical dependence and pain at injection site.
Drug Interactions
1. Monitor E.C.G., V.S. and oxygen saturation continuously.
2. Closely monitor level of consciousness and airway patency.
3. Use with extreme caution for patients with C.O.P.D. and cor pulmonale,
elderly, asthmatics, other CNS depressant use.
Special Considerations
1. May reverse effects with naloxone
2. May worsen bradycardias or heart blocks associated with inferior wall MI's.
Note: Feel free to discuss this medication and your experiences in administering it in an emergency or hospital based setting on our message board
