Morphine Injection

437 interactions 767 cited references

Also sold as: Astramorph® PF Duramorph Duramorph® Infumorph Infumorph® Kadian Mitigo MS Contin

About Morphine Injection

Morphine injection is used to relieve moderate to severe pain. Morphine is in a class of medications called opiate (narcotic) analgesics. It works by changing the way the brain and nervous system respond to pain. Read the full Morphine Injection drug information page →

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Aug 9, 2026 · Editorial policy · Data sources

Sources: FDA prescribing information (Structured Product Labeling), the published literature cited in each entry, DDInter 2.0 (a major open-access drug-interaction database), and legacy DrugBank interaction data distributed by the NIH's RxNav service (decommissioned in 2024) — analyzed and reviewed by our pharmacist team. How we build this library →

Most serious with: Samidorphan Safinamide Rasagiline Phenelzine Ozanimod Procarbazine

12 Contraindicated 409 Major 16 Moderate

All (437) Contraindicated (12) Major (409) Moderate (16)

Major

Morphine Injection Lapatinib Tykerb Increased morphine exposure and an increased risk of morphine-related adverse effects (hypotension, respiratory depression, profou... Details Morphine Injection Lasmiditan Reyvow Increased risk of serotonin syndrome (hypertension, hyperthermia, myoclonus, mental status changes) Details Morphine Injection Lemborexant Dayvigo An increased risk of CNS depression and potential next-day somnolence Details Morphine Injection Lenacapavir Sunlenca Increased morphine exposure and an increased risk of morphine-related adverse effects (hypotension, respiratory depression, profou... Details Morphine Injection Levocetirizine Xyzal Increased risk of CNS depression Details Morphine Injection Levodopa Inbrija An increased risk of CNS depression Details Morphine Injection Levomilnacipran Increased risk of serotonin syndrome Details Morphine Injection Levorphanol Xyvona Increased risk of respiratory and CNS depression and an increased risk of serotonin syndrome Details Morphine Injection Lisdexamfetamine Arynta Increased risk of serotonin syndrome Details Morphine Injection Lithium Increased risk of serotonin syndrome Details Morphine Injection Lofepramine Increased risk of serotonin syndrome Details Morphine Injection Lofexidine Increased risk of CNS depressant effects Details Morphine Injection Lonafarnib Zokinvy Increased morphine exposure and an increased risk of morphine-related adverse effects (hypotension, respiratory depression, profou... Details Morphine Injection Loprazolam Increased risk of profound sedation, respiratory depression, hypotension, coma and death Details Morphine Injection Lorazepam Ativan Increased risk of profound sedation, respiratory depression, hypotension, coma and death Details Morphine Injection Lorcaserin Increased risk of serotonin syndrome Details Morphine Injection Lormetazepam Increased risk of profound sedation, respiratory depression, hypotension, coma and death Details Morphine Injection Loxapine Adasuve Increased risk of urinary retention, severe constipation, and paralytic ileus and an increased risk of profound sedation, respirat... Details Morphine Injection Magnesium Oxybate Xywav An increased risk of CNS depression and clinically significant respiratory depression, obtundation, hypotension, profound sedation... Details Morphine Injection Maribavir Livtencity Increased morphine exposure and an increased risk of morphine-related adverse effects (hypotension, respiratory depression, profou... Details Morphine Injection Meclizine Antivert Increased risk of urinary retention, severe constipation, and paralytic ileus and an increased risk of profound sedation, respirat... Details Morphine Injection Medazepam Increased risk of profound sedation, respiratory depression, hypotension, coma and death Details Morphine Injection Melitracen Increased risk of serotonin syndrome Details Morphine Injection Melperone Increased risk of profound sedation, respiratory depression, hypotension, coma and death Details Morphine Injection Mepenzolate Increased risk of urinary retention, severe constipation, and paralytic ileus Details Morphine Injection Meperidine Demerol Increased risk of respiratory and CNS depression and an increased risk of serotonin syndrome Details Morphine Injection Mephobarbital Increased risk of profound sedation, respiratory depression, hypotension, coma and death Details Morphine Injection Meprobamate Increased risk of profound sedation, respiratory depression, hypotension, coma and death Details Morphine Injection Meptazinol Reduced analgesic effect or precipitation of withdrawal symptoms, and an increased risk of serotonin syndrome Details Morphine Injection Mesoridazine Increased risk of profound sedation, respiratory depression, hypotension, coma and death Details Morphine Injection Metaclazepam Increased risk of profound sedation, respiratory depression, hypotension, coma and death Details Morphine Injection Metaxalone Skelaxin Increased risk of serotonin syndrome, an increased risk of respiratory depression and an increased risk of CNS depression Details Morphine Injection Methadone Diskets Increased risk of respiratory and CNS depression and an increased risk of serotonin syndrome Details Morphine Injection Methamphetamine Desoxyn Increased risk of serotonin syndrome Details Morphine Injection Methdilazine Increased risk of profound sedation, respiratory depression, hypotension, coma and death Details Morphine Injection Methocarbamol Atmeksi Increased risk of profound sedation, hypotension, coma and respiratory depression Details Morphine Injection Methohexital Brevital Increased risk of profound sedation, respiratory depression, hypotension, coma and death Details Morphine Injection Methotrimeprazine Increased risk of profound sedation, respiratory depression, hypotension, coma and death Details Morphine Injection Methyclothiazide Reduced efficacy of diuretics Details Morphine Injection Methylnaltrexone Relistor Decreased opioid efficacy and precipitation of opioid withdrawal Details

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Educational information only, not medical advice. Always confirm interactions with your pharmacist or prescriber before making any change to your medications.