Mst Continus (Morphine Sulfate)

Morphine Sulfate is an opioid analgesic used to manage pain through central nervous system pathways.

• Moderate to severe acute pain: provides rapid analgesia for postoperative, traumatic, or injury‑related pain.
• Chronic cancer pain: offers sustained pain control for patients with malignant disease.
• Severe chronic non‑cancer pain: used when other analgesics are insufficient, under specialist supervision.

• Morphine Sulfate exerts its effect by binding as an agonist to mu‑opioid receptors in the central nervous system. Activation of these G‑protein‑coupled receptors inhibits adenylate cyclase activity, reduces calcium influx, and increases potassium efflux, leading to decreased neuronal excitability and suppression of pain signal transmission. The resulting analgesia is accompanied by sedation and respiratory depression at higher doses.

Morphine Sulfate may cause a range of adverse reactions, varying from mild to severe.

Common Side Effects

• Constipation: reduced gastrointestinal motility leading to hard stools.
• Nausea: feeling of sickness often accompanied by vomiting.
• Drowsiness: increased sleepiness and reduced alertness.
• Dry mouth: decreased salivary secretion causing oral dryness.
• Itching: mild pruritus, especially around the face.

Serious or Rare Side Effects

• Respiratory depression: slowed or shallow breathing that can be life‑threatening.
• Severe hypotension: marked drop in blood pressure causing dizziness or fainting.
• Opioid dependence: risk of physical and psychological addiction with prolonged use.
• Adrenal insufficiency: rare suppression of adrenal gland function.
• Anaphylaxis: severe allergic reaction with hives, swelling, and airway compromise.

When prescribing Morphine Sulfate, clinicians should observe several safety precautions to minimize risk.

• Assess pain severity: confirm that opioid therapy is appropriate for the patient’s level of pain.
• Evaluate respiratory function: avoid use in patients with compromised breathing or sleep‑apnea.
• Review concomitant CNS depressants: limit combined use with benzodiazepines or alcohol.
• Monitor for signs of dependence: conduct regular assessments for misuse or addiction.
• Adjust dose in renal/hepatic impairment: consider reduced dosing or increased monitoring.
• Store at below 25°C: keep in the original container, protect from moisture and direct sunlight.

Morphine Sulfate can interact with other medications, altering its efficacy or safety profile.

Major Interactions (Avoid)

• Other opioids: additive respiratory depression and sedation.
• CNS depressants (e.g., benzodiazepines, barbiturates): increased risk of profound sedation and respiratory failure.
• MAO inhibitors: can precipitate severe hypertension or serotonin syndrome.

Moderate Interactions (Monitor Closely)

• CYP3A4 inhibitors (e.g., ketoconazole, erythromycin): may raise morphine plasma levels.
• CYP3A4 inducers (e.g., rifampin, carbamazepine): may reduce analgesic effect.
• Anticholinergics: may exacerbate constipation.
• Diuretics: can enhance hypotensive effects.