Morphine Sulfate

What it is and how it works

Mechanism of Action Morphine is a full opioid agonist and is relatively selective for the mu-opioid receptor, although it can bind to other opioid receptors at higher doses. The principal therapeutic action of morphine is analgesia. Like all full opioid agonists, there is no ceiling effect for analgesia with morphine. Clinically, dosage is titrated to provide adequate analgesia and may be limited by adverse reactions, including respiratory and CNS depression. The precise mechanism of the analgesic action is unknown.

Indications

Morphine sulfate tablets are indicated for the management of: adult and pediatric patients weighing at least 50 kg and above with acute pain severe enough to require an opioid analgesic and for which alternative treatments are inadequate. adults with chronic pain severe enough to require an opioid analgesic and for which alternative treatments are inadequate. Limitations of Use: Because of the risks of addiction, abuse, and misuse with opioids, which can occur at any dosage or duration, , reserve morphine sulfate tablets for use in patients for whom alternative treatment options (e.g., non-opioid analgesics or opioid combination products): Have not been tolerated or are not expected to be tolerated, Have not provided adequate analgesia or are not expected to provide adequate analgesia Morphine sulfate tablets should not be used for an extended period of time unless the pain remains severe enough to require an opioid analgesic and for which alternative treatment options continue to be inadequate.

Dosage and administration (summary)

Morphine sulfate tablets should be prescribed only by healthcare professionals who are knowledgeable about the use of opioids and how to mitigate the associated risks. Use the lowest effective dosage for the shortest duration of time consistent with individual patient treatment goals. Reserve titration to higher doses of morphine sulfate tablets for patients in whom lower doses are insufficiently effective and in whom the expected benefits of using a higher dose opioid clearly outweigh the substantial risks.

Contraindications

Morphine sulfate tablets are contraindicated in patients with: Significant respiratory depression . Acute or severe bronchial asthma in an unmonitored setting or in the absence of resuscitative equipment . Concurrent use of monoamine oxidase inhibitors (MAOIs) or use of MAOIs within the last 14 days . Known or suspected gastrointestinal obstruction, including paralytic ileus . Hypersensitivity to morphine (e.g., anaphylaxis) . Significant respiratory depression.

Warnings and precautions

Opioid-Induced Hyperalgesia and Allodynia: Opioid-Induced Hyperalgesia (OIH) occurs when an opioid analgesic paradoxically causes an increase in pain, or an increase in sensitivity to pain. If OIH is suspected, carefully consider appropriately decreasing the dose of the current opioid analgesic or opioid rotation. Life-Threatening Respiratory Depression in Patients with Chronic Pulmonary Disease or in Elderly, Cachectic, or Debilitated Patients: Regularly evaluate, particularly during initiation and titration.

Pregnancy

Pregnancy Risk Summary: U se of opioid analgesics for an extended period of time during pregnancy can cause neonatal opioid withdrawal syndrome . There are no available data with morphine sulfate tablets in pregnant women to inform a drug-associated risk for major birth defects and miscarriage.

Storage and supply

Morphine sulfate tablets 15 mg : Each tablet contains 15 mg morphine sulfate, USP (equivalent to 11.25 mg morphine) and is a white, round, biconvex tablet, scored on one side and debossed “M 15” on other side.

Source: Morphine Sulfate (Morphine Sulfate) — US FDA prescribing information, 2025-10-10, DailyMed. Summarised and shortened; the full label governs. Iranian registration, indications and labelling may differ.