Morphine Sulfate: Drug Information

What You Need To Know About Morphine

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Morphine Sulfate is a narcotic opioid analgesic, which means that it provides pain relief and is made from the poppy plant. Morphine is a powerful pain reliever used for both acute (short term) and chronic pain. It is also used, much less frequently, as a cough suppressant, for difficulty breathing and to stop diarrhea.

Morphine is the first known painkiller. It was discovered in the early 1800s and was distributed under the name Laudanum. But poppy-based medicines similar to morphine were used as early as the 1500s. It is one of many medications commonly used during and after surgery.

Centuries later, morphine is available in a wide variety of forms including long and short acting forms, and is used to treat pain caused by a variety of diseases, illnesses and injuries. Morphine, is effective, inexpensive and readily available, which makes it a valuable medication around the world.

Names For Morphine

Morphine is prescribed under a variety of names, abbreviations and both brand and generic names. Those names include MS Contin, Avinza, Kadian, Oramorph, MOS, Duramorph, Morphitec, MS, Roxanol, and epidural morphine.

How It's Administered

Morphine is available in a variety of forms, and it can be given as an injection, pill, epidural, oral solution, suppository or sublingually (under the tongue). Taking morphine as directed is important, as are realistic expectations. Some pain is to be expected and does not mean that more pain medication is necessary.

Side Effects

Common side effects of morphine include:

  • Constipation: After surgery, it is important to prevent constipation, which can become a major complication.
  • Decreased coughing
  • Loss of appetite
  • Sleepiness
  • Dizziness

Associated Risks 

Every drug has risks, and morphine is no exception. Risks are increased with higher doses, long-term use and especially inappropriate use without a prescription. To minimize these risks, follow the instructions on your prescription and only take the medication when appropriate for pain control.

  • Headache
  • Depressed breathing (breathing too slowly or too shallowly)
  • Confusion
  • Memory problems
  • Severe constipation
  • Anxiety
  • Memory problems
  • Sleep disturbances
  • Tolerance
  • Addiction


Patients who are nursing should consult their physician before taking morphine, as it may be expressed in breast milk. In pregnant women, prolonged use of morphine may result in the baby experiencing morphine withdrawal shortly after birth. 

Patients with constipation may experience a worsening of symptoms. Those with other intestine conditions should use morphine with caution as it can slow digestion and result in a worsening condition. Morphine should also be used with caution in people with respiratory conditions including COPD or asthma.

The elderly may be more sensitive to morphine. Their dosages may need to be adjusted to prevent an overdose or pronounced side effects.

Tolerance, Addiction, and Abuse

Morphine, like many prescription drugs, may require larger doses for pain control when used for extended periods of time. Over time, the body can develop a tolerance for the medication and will require more medication to experience the same level of effectiveness.

When used according to your doctor’s directions, morphine, like all prescription drugs, carries a low risk of addiction. People with chronic pain who use morphine for long periods of time may become physically addicted to the medication, meaning that they will experience signs and symptoms of withdrawal when they do not take the drug. Physical addiction does not necessarily mean the drug is a problem. For example, a cancer patient could become physically addicted to the medication. However, the drug will continue to be given as need for pain relief.

Physical addiction is not the same as mental addiction. When people use the drug inappropriately (seeking a “high” or euphoria instead of pain relief), they can become emotionally dependent on the drug. Misuse of morphine can take on a number of forms including mixing it with other drugs such as alcohol and taking larger or more frequent doses than necessary for pain management.

A Word From Verywell

Morphine is a drug that has been used for decades with great success in treating pain. While addiction remains a major problem in the United States, when taken appropriately morphine remains both safe and effective for short term use. Long term use should be monitored closely and will be safest when taking the minimum amount to decrease pain to tolerable levels.

View Article Sources
  • Morphine. University of Maryland Medical Center. Accessed July, 2009.