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Drugs & Supplements


What is Imuran?

Azathioprine (Imuran) is an immune system-suppressing drug. That means it can theoretically halt the attack of the immune system on your nerves. The drug can be used to slow the progression of MS in people who are not responding well to other treatments.

Imuran might also be used with other disease-modifying therapies, such as Avonex, to boost its effect.

How is Imuran taken?

Imuran is generally taken orally, in the form of tablets.

Your white blood cell count and your weight will determine the dose that is prescribed. The starting dose is low and is slowly increased. Imuran is generally taken twice a day. It is available in 50 mg. tablets, which are easily broken in half if necessary.

Your prescription label tells you how much to take at each dose and how often to take it. Follow these instructions carefully, and ask your pharmacist or doctor to explain any instructions you do not understand.

It is important that you take this medicine regularly as prescribed. Do not stop taking it and do not take more or less of the medicine than is prescribed.

When taking Imuran, keep the following tips in mind:

  • Some mild nausea often occurs when you start taking Imuran. This discomfort is expected and will go away as your body gets used to the medicine. If you have extreme nausea with vomiting, contact your doctor.
  • While you are taking this medicine, you might be asked to have regular blood tests (blood cell counts and liver function tests) to evaluate the medicine's effectiveness and to monitor your response to the medicine.
  • Keep all appointments with your doctor and the laboratory. Your doctor might reduce or even stop Imuran when you are being treated for certain infections. This allows your body to effectively fight the infection.
  • Be sure you always have enough medicine on hand. Check your supply before holidays or other occasions when you might be unable to fill your prescription.
  • Do not have any vaccinations without your doctor's approval.
  • Take precautions to avoid infection while taking this medicine. Avoid anyone who might have an infection and report any signs of infection to your doctor.

What are the possible side effects associated with Imuran therapy?

Side effects may include:

  • Increased stomach irritation
  • Nausea and vomiting
  • Changes in hair color and texture, along with hair loss (These changes are usually temporary).
  • Loss of appetite
  • Blood in the urine or stool
  • Unusual bruising
  • Fatigue
  • Development of mouth sores and ulcers
  • Increased risk of infection (Because Imuran is an immunosuppressive medicine, it can lower the number of white blood cells in your blood, increasing the chance of infection).

It's important to remember that not everyone experiences all of these side effects. This medicine is generally well tolerated. Even though some of the side effects could be very serious, remember that precautions will be taken to detect these side effects and treat them before they become harmful.

What should I do if I forget to take a dose?

If you forget to take a dose, take it as soon as you remember and then continue to follow your regular dosing schedule.

How should I store Imuran?

  • Store this medicine at room temperature.
  • DO NOT store this drug in direct heat or light.
  • DO NOT store this medicine in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture might cause it to break down.
  • Keep this medicine in the container it came in, tightly sealed.
  • Do not keep outdated medicine.
  • Keep this and other medicines out of the reach of children.

Warning: Call your doctor right away if you have any of these warning signs of infection:

  • Fever over 100°F (38°C)
  • Sweats or chills
  • Skin rash
  • Pain, tenderness, redness, or swelling
  • Wound or cut that won't heal
  • Red, warm, or draining sore
  • Sore throat, scratchy throat, or pain when swallowing
  • Sinus drainage, nasal congestion, headaches, or tenderness along upper cheekbones
  • Persistent, dry, or moist cough that lasts more than two days
  • White patches in your mouth or on your tongue
  • Nausea, vomiting, or diarrhea
  • Flu-like symptoms (chills, aches, headache, and fatigue) or generally feeling "lousy"
  • Trouble urinating: pain or burning, constant urge, or frequent urination
  • Bloody, cloudy, or foul-smelling urine, or black, tarry stools
  • If you have any other symptoms that cause concern

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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or health care provider. Please consult your health care provider for advice about a specific medical condition. This document was last reviewed on: 10/8/2008...#9407