Imuran (azathioprine) is a medication used after kidney transplantation and also for rheumatoid arthritis. It's not a first choice medication because of many side effects. Your provider may also use Imuran (azathioprine) for other indications as well, although these are off-label (not FDA-approved) uses.
To prevent the body from rejecting a transplanted kidney
Rheumatoid arthritis
Imuran (azathioprine) is in a drug class known as immunosuppressants. This means it weakens your body's immune response. It's important to lower your immune response after a kidney transplant so that your body doesn't attack the new kidney. If you have rheumatoid arthritis, it can stop your immune system from attacking your joints.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Black, tarry stools
bleeding gums
blood in the urine or stools
chills
hoarseness
lower back or side pain
painful or difficult urination
pinpoint red spots on the skin
sores, ulcers, or white spots on the lips or in the mouth
swollen glands
unusual bleeding or bruising
unusual tiredness or weakness
Less common
Cloudy urine
fever sores on the skin
general feeling of illness
greatly decreased frequency of urination or amount of urine
skin rash
swelling of the feet or lower legs
yellow skin or eyes
Rare
clay-colored stools
dark urine
decreased appetite
diarrhea (severe)
fast heartbeat
fever (sudden)
headache
indigestion
loss of appetite
muscle or joint pain
nausea (severe)
pains in the stomach, side, or abdomen, possibly radiating to the back
redness or blisters on the skin
stomach pain or tenderness
swelling of the feet or lower legs
unusual feeling of discomfort or illness (sudden)
vomiting (severe)
Incidence not known
Difficulty with breathing
difficulty with moving
fat in the stool
general feeling of illness
pale skin
sores on the skin
stomach cramps
sudden loss of weight
troubled breathing with movement
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common
Hair loss or thinning of the hair
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Works well for the treatment of rheumatoid arthritis, although it's not commonly used unless other medications don't work
Lowers the pain, stiffness, and swelling caused by rheumatoid arthritis
Available in a generic form which is more affordable
Can be used in people who have had a kidney transplant and are planning to become pregnant
Regular blood tests are required
Raises risk of getting an infection
Not a first choice medication because of many side effects
Take the medication after meals to help lower the chance of nausea and vomiting.
This medication makes your body more susceptible to infection so be sure to wash your hands often and keep distance from people who are sick.
Avoid sun excessive sun exposure while taking this medication because it is associated with certain types of cancers. Always use sunscreen and wear a long-sleeved shirt, pants, hat, and sunglasses.
This medication can cause birth defects. It is important for both men and women to use contraception during sexual intercourse. Talk to your provider about other options if you become or would like to become pregnant.
Some people might not be as good at metabolizing this medication. This can cause higher levels of the medication in their body and increase the chance of having side effects. This enzyme is called thiopurine methyltransferase (TPMT). Ask your healthcare provider if you should be tested for this to find out if you have less of this enzyme.
Imuran (azathioprine) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Long-term use
Long-term use of Imuran (azathioprine) can cause skin cancer, as well as lymphoma (a cancer of the immune system). Limit your exposure to sunlight and ultraviolet light, wear protective clothing and use sunblock.
Risk factors: Kidney transplant rejection | Higher doses
Imuran (azathioprine) can lower the amount of your red and white blood cells. Your healthcare provider will order tests to make sure the level of Imuran (azathioprine) in your blood is safe.
Risk factors: Long-term use | Receiving live vaccines like varicella (chicken pox), yellow fever or the measles, mumps and rubella (MMR) vaccine
If you take Imuran (azathioprine) for a long time, you are more likely to get sick from infections, which can be very serious. Be sure to stay away from people who are sick. Wash your hands often. Also, some vaccines like varicella (chicken pox), yellow fever or the MMR vaccine are considered live vaccines and these should not be received since Imuran (azathioprine) can weaken your immune system. Talk to your healthcare provider right away if you suddenly have muscle weakness, changes in your speech and vision, or develop a fever.
A rise in your liver enzymes could be a sign that the medication is hurting your liver. This usually occurs within the first six months of using the medication and it will go away once the medication is stopped.
The dosing for this medication is different for everyone. It depends on your weight and other factors your healthcare provider considers.
Kidney transplantation: Once you have a kidney transplanted and are stable, the typical dosing is 1 mg to 3 mg per kilogram of bodyweight by mouth once daily. This usually comes out to 50 mg to 150 mg per day.
Rheumatoid arthritis: The typical dosing is 1 mg per kilogram of bodyweight given by mouth once daily or divided into two doses per day.
Your dose will change if your provider needs to manage your condition or lower side effects.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
To prevent the body from rejecting a transplanted kidney
Rheumatoid arthritis
Prevention of kidney, heart, or liver transplant rejection in people ages 3 months and older; taken with other anti-rejection medications
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