Azathioprine

Why this is used

Azathioprine is used with other medications to prevent rejection of kidney transplants. It is also used to treat severe rheumatoid arthritis (a condition in which the body attacks its own joints, causing pain and swelling) when other medications and treatments have not helped. Azathioprine is in a class of medications called immunosuppressants. It works by weakening the body's immune system so it will not attack the transplanted organ or the joints.

How to take it

Azathioprine comes as a tablet to take by mouth. It is usually taken once or twice a day after meals. To help you remember to take azathioprine, take it around the same time(s) every day. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take azathioprine exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor. If you are taking azathioprine to treat rheumatoid arthritis, your doctor may start you on a low dose and gradually increase your dose after 6-8 weeks and then not more than once every 4 weeks. If you are taking azathioprine to prevent kidney transplant rejection, your doctor may start you on a high dose and decrease your dose gradually as your body adjusts to the transplant. Azathioprine controls rheumatoid arthritis but does not cure it. It may take some time before you feel the full benefit of azathioprine. Azathioprine prevents transplant rejection only as long as you are taking the medication. Continue to take azathioprine even if you feel well. Do not stop taking azathioprine without talking to your doctor.

Side effects

<p></p> <p></p> <p></p> <p>Azathioprine may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

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nausea</li>
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vomiting</li>
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diarrhea</li>
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muscle aches</li></ul></p> <p></p> <p>Some side effects can be serious. The following symptoms are uncommon, but if you experience any of them or those listed in the IMPORTANT WARNING section, call your doctor immediately.

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mouth sores</li>
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cough</li>
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lack of energy</li>
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loss of appetite</li>
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pain in the upper right part of the stomach</li>
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yellowing of the skin or eyes</li>
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flu-like symptoms</li>
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rash</li>
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blurred vision</li>
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stomach pain</li></ul>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 [at <a href='http://www.fda.gov/Safety/MedWatch'>http://www.fda.gov/Safety/MedWatch</a>] or by phone [1-800-332-1088].</p>

Precautions

Before taking azathioprine, tell your doctor and pharmacist if you are allergic to azathioprine or any other medications. tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking. Be sure to mention any of the medications mentioned in the IMPORTANT WARNING section and the following: allopurinol (Zyloprim); angiotensin-converting enzyme (ACE) inhibitors such as benazepril (Lotensin), captopril (Capoten), enalapril (Lexxel, Vasotec), fosinopril (Monopril), lisinopril (Prinivil, Zestril), moexipril (Univasc), perindopril (Aceon), quinapril (Accupril), ramipril (Altace), and trandolapril (Mavik, Tarka); anticoagulants ('blood thinners') such as warfarin (Coumadin); antimalarials such as chloroquine (Aralen), hydroxychloroquine (Plaquenil), mefloquine (Lariam), primaquine, proguanil (Malarone), pyrimethamine (Daraprim), and quinine; cancer chemotherapy medications; co-trimoxazole (Bactrim, Septra, Sulfatrim); cyclosporine (Neoral, Sandimmune); gold compounds such as auranofin (Ridaura) and aurothioglucose (Aurolate, Solganal); methotrexate (Rheumatrex); penicillamine (Cuprimine, Depen); sirolimus (Rapamune); and tacrolimus (Prograf). tell your doctor if you have any type of infection, or if you have or have ever had kidney, liver, or pancreas disease. if you are having surgery, including dental surgery, tell the doctor or dentist that you are taking azathioprine. do not have any vaccinations (e.g., measles or flu shots) during or after your treatment without talking to your doctor. you should know that azathioprine may decrease your ability to fight infection. Stay away from people who are sick, and wash your hands often.

Overdose

In case of overdose, call your local poison control center at 1-800-222-1222. If the victim has collapsed or is not breathing, call local emergency services at 911. Symptoms of overdose may include:

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nausea</li>
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vomiting</li>
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diarrhea</li>
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sore throat, fever, chills, and other signs of infection</li></ul>
Educational reference only — talk to a pharmacist or prescriber about Azathioprine.