morphine sulfate

Drug Name

Generic Name : morphine sulfate

Brand Name:

  • Timed-release: Avinza, Kadian, M-Eslon (CAN), MS Contin, Oramorph SR
  • Oral solution: Roxanol, Roxanol T
  • Rectal suppositories: RMS
  • Injection: Astramorph PF, Duramorph
  • Preservative-free concentrate for microinfusion devices for intraspinal use: Infumorph
  • Liposome injection: DepoDur

Classification: Opioid agonist analgesic

Pregnancy Category C
Controlled Substance C-II 

Dosage & Route
ADULTS

Oral

  • Initial dose, 15 mg PO daily, as a single dose in evening. One-third to one-sixth as effective as parenteral administration because of first-pass metabolism; 10–30 mg q 4 hr PO. CR: 30 mg q 8–12 ;hr PO or as directed by physician; Kadian: 20–100 mg PO daily–24-hr release system; MS Contin: 200 mg PO q 12 hr; Avinza: 30 mg PO daily; if opioid naive, increase by 30 mg (or lower) increments q 4 days.

IM or subcutaneous

  • 10 mg (range, 5–20 mg)/70 kg q 4 hr or as directed by physician.

IV

  • 2.5–15 mg/70 kg of body weight in 4–5 mL water for injection administered over 4–5 min, or as directed by physician. Continuous IV infusion: 0.1–1 mg/mL in D5W by controlled infusion device.

Rectal

  • 10–30 mg q 4 hr or as directed by physician.

Epidural

  • Initial injection of 5 mg in the lumbar region may provide pain relief for up to 24 hr. If adequate pain relief is not achieved within 1 hr, incremental doses of 1–2 mg may be given at intervals sufficient to assess effectiveness, up to 10 mg/24 hr. For continuous infusion, initial dose of 2–4 mg/24 hr is recommended. Further doses of 1–2 mg may be given if pain relief is not achieved initially.

Liposome injection

  • 10–15 mg by lumbar epidural injection using a catheter or needle prior to major surgery or after clamping the umbilical cord during cesarean section.

Intrathecal

  • Dosage is usually one-tenth that of epidural dosage; a single injection of 0.2–1 mg may provide satisfactory pain relief for up to 24 hr. Do not inject > 2 mL of the 5 mg/10 mL ampule or > 1 mL of the 10 mg/10 mL ampule. Use only in the lumbar area. Repeated intrathecal injections are not recommended; use other routes if pain recurs. For epidural or intrathecal dosing, use preservative-free morphine preparations only.
PEDIATRIC PATIENTS
  • Do not use in premature infants.

IM or subcutaneous

  • 0.05–0.2 mg/kg (up to 15 mg per dose) q 4 hr or as directed by physician.
GERIATRIC PATIENTS OR IMPAIRED ADULTS
  • Use caution. Respiratory depression may occur in the elderly, the very ill, those with respiratory problems. Reduced dosage may be needed.
Epidural
  • Use extreme caution; injection of < 5 mg in the lumbar region may provide adequate pain relief for up to 24 hr.
Intrathecal
  • Use lower dosages than recommended above for adults.
Therapeutic actions
  • Morphine is a phenanthrene derivative which acts mainly on the CNS and smooth muscles. It binds to opiate receptors in the CNS altering pain perception and response. Analgesia, euphoria and dependence are thought to be due to its action at the mu-1 receptors while respiratory depression and inhibition of intestinal movements are due to action at the mu-2 receptors. Spinal analgesia is mediated by morphine agonist action at the K receptor. Cough is suppressed by direct action on cough centre.
Indications
  • Relief of moderate to severe acute and chronic pain
  • Preoperative medication to sedate and allay apprehension, facilitate induction of anesthesia, and reduce anesthetic dosage
  • Analgesic adjunct during anesthesia
  • Component of most preparations that are referred to as Brompton’s cocktail or mixture, an oral alcoholic solution that is used for chronic severe pain, especially in terminal cancer patients
  • Intraspinal use with microinfusion devices for the relief of intractable pain
  • Treatment of pain following major surgery, ER liposome injection for single-dose administration by epidural route at the lumbar level
Adverse effects
  • Convulsions; nausea, vomiting, dry mouth, constipation; urinary retention; headache, vertigo; palpitations; hypothermia; pruritus, urticaria; tachycardia, bradycardia; blurred vision; miosis; dependency; drowsiness; lightheadedness; dizziness; sweating; dysphoria; euphoria.
  • Potentially Fatal: Respiratory depression; circulatory failure; hypotension; deepening coma; anaphylactic reactions.
Contraindications
  • Respiratory depression, acute or severe asthma; paralytic ileus; obstructive airway disease; acute liver disease; comatose patients; increased intracranial pressure; acute alcoholism. Pulmonary oedema resulting from a chemical respiratory irritant.
Nursing considerations
Assessment
  • History: Hypersensitivity to opioids; diarrhea caused by poisoning; labor or delivery of a premature infant; biliary tract surgery or surgical anastomosis; head injury and increased intracranial pressure; acute asthma, COPD, cor pulmonale, preexisting respiratory depression; acute abdominal conditions, CV disease, supraventricular tachycardias, myxedema, seizure disorders, acute alcoholism, delirium tremens, cerebral arteriosclerosis, ulcerative colitis, fever, kyphoscoliosis, Addison disease, prostatic hypertrophy, urethral stricture, recent GI or GU surgery, toxic psychosis, renal or hepatic impairment; pregnancy; lactation
  • Physical: T; skin color, texture, lesions; orientation, reflexes, bilateral grip strength, affect; P, auscultation, BP, orthostatic BP, perfusion; R, adventitious sounds; bowel sounds, normal output; urinary frequency, voiding pattern, normal output; ECG; EEG; LFTs, renal and thyroid function tests
Interventions
  • BLACK BOX WARNING: Caution patient not to chew or crush CR preparations.
  • WARNING: Dilute and administer slowly IV to minimize likelihood of adverse effects.
  • Tell patient to lie down during IV administration.
  • WARNING: Keep opioid antagonist and facilities for assisted or controlled respiration readily available during IV administration.
  • WARNING: Use caution when injecting IM or subcutaneously into chilled areas or in patients with hypotension or in shock; impaired perfusion may delay absorption; with repeated doses, an excessive amount may be absorbed when circulation is restored.
  • Reassure patients that they are unlikely to become addicted; most patients who receive opiates for medical reasons do not develop dependence syndromes.
  • BLACK BOX WARNING: Liposome preparation is for lumbar epidural injection only; it should not be given intrathecally, IV, or IM.
Teaching points
  • Take this drug exactly as prescribed. Avoid alcohol, antihistamines, sedatives, tranquilizers, and over-the-counter drugs.
  • Swallow controlled-release preparation (MS Contin, Oramorph SR) whole; do not cut, crush, or chew.
  • Do not take leftover medication for other disorders, and do not let anyone else take your prescription.
  • You may experience these side effects: Nausea, loss of appetite (take with food, lie quietly); constipation (use laxative); dizziness, sedation, drowsiness, impaired visual acuity (avoid driving or performing tasks that require alertness and visual acuity).
  • Report severe nausea, vomiting, constipation, shortness of breath or difficulty breathing, rash.