Morphine Injection

pronounced as (mor' feen)

Brand Name(s): Astramorph® PF, Duramorph®, Infumorph®, also available generically

Why is this medicine prescribed?

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.

Are there other uses for this medicine?

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Morphine injection comes as a solution (liquid) to inject intramuscularly (into a muscle) or intravenously (into a vein). It is usually injected once every 4 hours as needed. Use morphine injection at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Use morphine injection exactly as directed.

Your doctor may adjust your dose of morphine injection during your treatment, depending on how well your pain is controlled and on the side effects that you experience. Talk to your doctor about how you are feeling during your treatment with morphine injection.

If you have used morphine injection for longer than a few days, do not stop using it suddenly. If you suddenly stop using morphine injection, you may experience withdrawal symptoms including restlessness; teary eyes; runny nose; yawning; sweating; chills; muscle, back or joint pain; widening of the pupils; irritability; anxiety; weakness; stomach cramps; difficulty falling asleep or staying asleep; nausea; loss of appetite; vomiting; diarrhea; fast breathing; or fast heartbeat. Your doctor will probably decrease your dose gradually.

What special precautions should I follow?

Before using morphine injection,

  • tell your doctor and pharmacist if you are allergic to morphine, any other medications, or ingredients in morphine injection. Ask your pharmacist for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention any of the following: antihistamines (found in cold and allergy medications); cimetidine (Tagamet); cyclobenzaprine (Amrix); lithium (Lithobid, in Librax); medications for migraine headaches such as almotriptan (Axert), eletriptan (Relpax), frovatriptan (Frova), naratriptan (Amerge), rizatriptan (Maxalt), sumatriptan (Imitrex, in Treximet), and zolmitriptan (Zomig); mirtazapine (Remeron); 5HT3 serotonin blockers such as alosetron (Lotronex), dolasetron (Anzemet), granisetron (Kytril), ondansetron (Zofran, Zuplenz), or palonosetron (Aloxi); selective serotonin-reuptake inhibitors such as citalopram (Celexa), escitalopram (Lexapro), fluoxetine (Prozac, Sarafem, in Symbyax), fluvoxamine (Luvox), paroxetine (Brisdelle, Prozac, Pexeva), and sertraline (Zoloft); serotonin and norepinephrine reuptake inhibitors such as desvenlafaxine (Khedezla, Pristiq), duloxetine (Cymbalta), and venlafaxine (Effexor); tramadol (Conzip, Ultram, in Ultracet); trazodone; or tricyclic antidepressants ('mood elevators') such as amitriptyline, clomipramine (Anafranil), desipramine (Norpramin), doxepin (Silenor, Zonalon), imipramine (Tofranil), nortriptyline (Pamelor), protriptyline (Vivactil), and trimipramine (Surmontil). Also tell your doctor or pharmacist if you are taking or receiving the following monoamine oxidase (MAO) inhibitors or if you have stopped taking them within the past two weeks: isocarboxazid (Marplan), linezolid (Zyvox), methylene blue, phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), or tranylcypromine (Parnate). Many other medications may also interact with morphine, so be sure to tell your doctor about all the medications you are taking, even those that do not appear on this list. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor what herbal products you are taking, especially St. John's wort.
  • tell your doctor if you have or have ever had any of the conditions mentioned in the IMPORTANT WARNING section or paralytic ileus (condition in which digested food does not move through the intestines). Your doctor may tell you not to use morphine.
  • tell your doctor if you have or have ever had low blood pressure, or heart, liver, or kidney disease.
  • tell your doctor if you are breastfeeding.
  • you should know that this medication may decrease fertility in men and women. Talk to your doctor about the risks of using morphine.
  • you should know that this medication may make you drowsy. Do not drive a car or operate machinery until you know how this medication affects you.
  • you should know that morphine may cause dizziness, lightheadedness, and fainting when you get up too quickly from a lying position. To avoid this problem, get out of bed slowly, resting your feet on the floor for a few minutes before standing up.
  • you should know that morphine may cause constipation. Talk to your doctor about changing your diet or using other medications to prevent or treat constipation while you are using morphine.
  • if you are having surgery, including dental surgery, tell the doctor or dentist that you are using morphine.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do in case of overdose?

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help . If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

While using morphine injection, you should talk to your doctor about having a rescue medication called naloxone readily available (e.g., home, office). Naloxone is used to reverse the life-threatening effects of an overdose. It works by blocking the effects of opiates to relieve dangerous symptoms caused by high levels of opiates in the blood. Your doctor may also prescribe you naloxone if you are living in a household where there are small children or someone who has abused street or prescription drugs. You should make sure that you and your family members, caregivers, or the people who spend time with you know how to recognize an overdose, how to use naloxone, and what to do until emergency medical help arrives. Your doctor or pharmacist will show you and your family members how to use the medication. Ask your pharmacist for the instructions or visit the manufacturer's website to get the instructions. If symptoms of an overdose occur, a friend or family member should give the first dose of naloxone, call 911 immediately, and stay with you and watch you closely until emergency medical help arrives. Your symptoms may return within a few minutes after you receive naloxone. If your symptoms return, the person should give you another dose of naloxone. Additional doses may be given every 2 to 3 minutes, if symptoms return before medical help arrives.

Symptoms of overdose may include the following:

  • slow, shallow, or irregular breathing
  • difficulty breathing
  • sleepiness
  • unable to respond or wake up
  • cold, clammy skin
  • small pupils
  • slow heartbeat
  • blurred vision
  • nausea
  • fainting

What side effects can this medicine cause?

Morphine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • headache
  • dizziness
  • lightheadedness
  • mood changes

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

  • seizures
  • slowed breathing
  • long pauses between breaths
  • shortness of breath
  • agitation, hallucinations (seeing things or hearing voices that do not exist), fever, sweating, confusion, fast heartbeat, shivering, severe muscle stiffness or twitching, loss of coordination, nausea, vomiting, or diarrhea
  • nausea, vomiting, loss of appetite, weakness, or dizziness
  • inability to get or keep an erection
  • irregular menstruation
  • decreased sexual desire
  • itching
  • rash
  • hives

Morphine may cause other side effects. Call your doctor if you have any unusual problems while you are using this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( http://www.fda.gov/Safety/MedWatch ) or by phone (1-800-332-1088).

What other information should I know?

Keep all appointments with your doctor and laboratory. Your doctor may order certain lab tests to check your body's response to morphine.

Before having any laboratory test (especially those that involve methylene blue), tell your doctor and the laboratory personnel that you are using morphine.

This prescription is not refillable. If you are using morphine to control your pain on a long term basis, be sure to schedule appointments with your doctor so that you do not run out of medication. If you are using morphine on a short-term basis, call your doctor if you continue to experience pain after you finish the medication.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

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