Hydromorphone

What is Hydromorphone? ¹

• Semi-synthetic opioid analgesic derived from morphine.
• Used for the management of moderate to severe pain.

Mechanism of Action & Pharmacokinetics ¹²

• Primarily acts on mu-opioid receptors in the central nervous system (CNS) to produce analgesia.
• Onset in 30-60 minutes (PO) and 10-15 minutes (IV), half life 2-3 hours ³
• Binds to opioid receptors leading to inhibition of ascending pain pathways, altering the perception of and response to pain.
• Metabolized in the liver by glucuronidation, producing dihydromorphine and dihydroisomorphine (active) and hydromorphone-3-glucuronide (inactive)
  • hydromorphone-3-glucuronide can accumulate in renal failure which can cause cognitive effects and neuroexcitation ²
• Excreted primarily through the kidneys.

Pharmacodynamics ¹²

Cardiovascular

• Can cause mild to moderate hypotension due to peripheral vasodilation.
• Minimal effects on myocardial contractility, but may cause bradycardia in some patients.

Respiratory

• Depresses respiratory centers in the brainstem, leading to decreased respiratory rate and minute ventilation. Often compensatory increased tidal volume occurs ¹
• Risk of respiratory depression increases with dose and concomitant use of other CNS depressants.

Indications ¹

• Management of moderate to severe pain where the use of an opioid analgesic is appropriate.
• Often used in postoperative pain management, cancer pain, and severe acute pain.

Dosage ²

• Oral:
  • 2 to 4 mg every 4 to 6 hours as needed for pain.
• Intravenous (IV):
  • 0.2 to 1 mg every 2 to 3 hours as needed for pain.
  • 5-15 mcg/kg in pediatrics
• Patient-Controlled Analgesia (PCA):
  • Initial demand dose: 0.1 to 0.2 mg IV; lockout interval typically 6 to 10 minutes.
• Dosage should be adjusted based on the patient's response, tolerance, and severity of pain.

Contraindications ¹²

• Hypersensitivity to hydromorphone or any of its components.
• Severe respiratory depression without resuscitative equipment or monitoring.

Complications ¹²⁴

• Respiratory depression, which can be severe and life-threatening, especially in opioid-naive patients.
• Common opioid-related side effects include nausea, vomiting, constipation, pruritus, and sedation.
• Long-term use may lead to tolerance, physical dependence, and opioid use disorder.
• Risk of hypotension, especially in patients with compromised blood pressure or on concomitant medications that lower blood pressure.

References