Health Library

Morphine (By injection)

Morphine (MOR-feen)

Treats moderate to severe pain. This medicine is a narcotic analgesic.

Brand Name(s):

Duramorph, Infumorph 200, Infumorph 500, Mitigo

When This Medicine Should Not Be Used:

How to Use This Medicine:

Injectable

• Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine may be given through a needle (a shot) or an IV catheter (a small tube). It may be given under your skin, into a muscle, into a vein, or into your back.
• A nurse or other health provider will give you this medicine.
• You may be taught how to give your medicine at home. Make sure you understand all instructions before giving yourself an injection. Do not use more medicine or use it more often than your doctor tells you to.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Do not use this medicine if you are using or have used an MAO inhibitor within the past 14 days.
• Some medicines can affect how morphine works. Tell your doctor if you are using any of the following:
  • Cimetidine, clopidogrel, mirtazapine, prasugrel, ticagrelor, tramadol, trazodone
  • Diuretic (water pill)
  • Medicine to treat depression (including SNRIs, SSRIs, TCAs)
  • Triptan medicine for migraine headaches
• Do not drink alcohol while you are using this medicine.
• Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, and alcohol. Tell your doctor if you are using buprenorphine, butorphanol, nalbuphine, pentazocine, or a muscle relaxer (including cyclobenzaprine, metaxalone).

Warnings While Using This Medicine:

• Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, heart disease, heart attack, low blood pressure, lung or breathing problems (including asthma, COPD, sleep apnea), adrenal problems, or a history of brain tumor, head injury, seizures, or drug or alcohol abuse.
• This medicine may cause the following problems:
  • High risk of overdose, which can lead to death
  • Respiratory depression (serious breathing problem that can be life-threatening)
  • Sleep-related breathing problems (including sleep apnea, sleep-related hypoxemia)
  • Worsening of pain
  • Adrenal gland problem
  • Low blood pressure
  • Increased risk of seizures
  • Serotonin syndrome (when used with certain medicines)
• This medicine may make you dizzy, drowsy, or lightheaded. Do not drive or do anything else that could be dangerous until you know how this medicine affects you. Sit or lie down if you feel dizzy. Stand up slowly.
• This medicine can be habit-forming. Do not use more than your prescribed dose. Call your doctor if you think your medicine is not working.
• Do not stop using this medicine suddenly. Your doctor will need to slowly decrease your dose before you stop it completely.
• This medicine could cause infertility. Talk with your doctor before using this medicine if you plan to have children.
• This medicine may cause constipation, especially with long-term use. Ask your doctor if you should use a laxative to prevent and treat constipation.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Anxiety, restlessness, fast heartbeat, fever, sweating, muscle spasms, nausea, vomiting, diarrhea, seeing or hearing things that are not there
• Blue lips, fingernails, or skin
• Changes in skin color, dark freckles, cold feeling, tiredness, weight loss
• Extreme dizziness, drowsiness, or weakness, shallow breathing, slow heartbeat, seizures, and cold, clammy skin
• Lightheadedness, dizziness, fainting
• Seizures
• Trouble breathing
• Worsening of pain, increased sensitivity to pain

If you notice these less serious side effects, talk with your doctor:

• Constipation
• Sleepiness
• Sweating

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 9/6/2024