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- What is azathioprine, and how does it work (mechanism of action)?
- What brand names are available for azathioprine?
- Is azathioprine available as a generic drug?
- Do I need a prescription for azathioprine?
- What are the side effects of azathioprine?
- What is the dosage for azathioprine?
- Which drugs or supplements interact with azathioprine?
- Is azathioprine safe to take if I'm pregnant or breastfeeding?
- What else should I know about azathioprine?
What is the dosage for azathioprine?
The initial dose for preventing organ rejection is 3 to 5 mg/kg (oral or IV) daily, starting at the time of transplantation or in some cases 1 to 3 days before transplantation. The initial off-label dose for treating rheumatoid arthritis is 1.0 mg/kg (50 to 100 mg, oral or IV) as a single dose or twice daily. Doses may be increased by 0.5 mg/kg daily up to a maximum dose of 2.5 mg/kg per day. Dosing for other off-label use may vary according to what disease is being treated; in general, off-label use should be done by an experienced medical specialist. Azathioprine should be taken with food.
Which drugs or supplements interact with azathioprine?
Allopurinol (Zyloprim) that is used for treating increased blood levels of uric acid and preventing gout increases azathioprine levels in the blood which may increase the risk of side effects from azathioprine. Therefore, it is important to reduce the dose of azathioprine by approximately 1/3 to 1/4 in patients taking allopurinol. The use of angiotensin-converting enzyme (ACE) inhibitors to control high blood pressure in patients taking azathioprine has been reported to induce anemia (low levels of red blood cells) and severe leukopenia (low levels of white blood cells). Azathioprine reduces blood levels of the blood thinner, warfarin (Coumadin), and thus may reduce the blood thinning effect of warfarin.
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