A Comprehensive Guide to Azathioprine: Uses, Dosage, Side Effects, and More

Azathioprine: Brand Name and Generic

Azathioprine is a medication that is often prescribed under the US brand name Imuran (Azathioprine).

Pharmacologic Category of Azathioprine

Azathioprine falls under the pharmacologic category of immunosuppressant drugs. It is specifically an antimetabolite, which means it interferes with the metabolism of cells, particularly those of the immune system. Other medications in this category include Methotrexate, Mercaptopurine (Purinethol), and Mycophenolate Mofetil (CellCept).

Dosing

Azathioprine is used to treat a range of diseases in adults. The exact dosage, frequency, and duration of treatment can vary depending on the specific disease. It is crucial to note that dosing adjustments should only be made under the guidance of a healthcare provider.
Here is a list of diseases that Azathioprine can treat, along with typical dosing guidelines:
Rheumatoid Arthritis: 1 mg/kg/day initially, increase by 0.5 mg/kg/day every 4 weeks (up to 2.5 mg/kg/day)
Systemic Lupus Erythematosus: 1-3 mg/kg/day
Inflammatory Bowel Disease (including Crohn’s Disease and Ulcerative Colitis): 2-3 mg/kg/day
Autoimmune Hepatitis: 1-2 mg/kg/day
Dermatomyositis and Polymyositis: 1-3 mg/kg/day
Pemphigus Vulgaris: 1-3 mg/kg/day
Myasthenia Gravis: 1-3 mg/kg/day
Chronic Active Hepatitis: 1-2 mg/kg/day
Vasculitis: 2 mg/kg/day
Psoriasis: 1-2.5 mg/kg/day
Sarcoidosis: 2-3 mg/kg/day
Idiopathic Thrombocytopenic Purpura: 1-2 mg/kg/day
Autoimmune Hemolytic Anemia: 1-2 mg/kg/day
Atopic Dermatitis: 1-3 mg/kg/day
Severe or Recalcitrant Atopic Dermatitis: 1-3 mg/kg/day
It’s important to remember that the exact dosing will depend on several factors, including the severity of the disease, the individual’s overall health, and how they respond to the medication.

Dosage Forms and Strengths

Azathioprine is available in the following dosage forms and strengths:
Tablet: 50 mg
Injection: 100 mg

Administration Instructions

Azathioprine can be taken orally with or without food. If it upsets your stomach, try taking it with food. If you are taking the tablet form, swallow it whole without crushing, chewing, or breaking it. For the injectable form, a healthcare provider will typically administer it.

Adverse Reactions and Side Effects

Like all medications, Azathioprine can cause side effects. However, not everyone experiences them, and when they do occur, they’re usually manageable. Here are some possible side effects:
Nausea and vomiting (Common): These are common side effects of many medications, including Azathioprine. They occur because the medication can irritate the stomach lining. Drinking plenty of fluids and eating small, frequent meals can help manage these symptoms.
Diarrhea (Common): This occurs as the body adjusts to the medication. It’s usually temporary but inform your doctor if it persists.
Leukopenia (less common): This refers to a decrease in the number of white blood cells, which are crucial for fighting infections. Azathioprine suppresses the immune system, which can result in leukopenia.
Hepatotoxicity (Rare): Azathioprine can, in rare cases, cause liver damage. Regular monitoring of liver function is necessary while on this medication.
Increased susceptibility to infections (Common): Since Azathioprine suppresses the immune system, you may be more prone to infections. It’s important to maintain good hygiene and avoid contact with sick individuals.

Contraindications to Taking Azathioprine

Contraindication refers to a specific situation in which a drug or procedure should not be used because it may be harmful to the person. Here are some contraindications for Azathioprine:
Hypersensitivity to Azathioprine: If you have previously had an allergic reaction to Azathioprine, you should not take it. Symptoms of an allergic reaction can include hives, difficulty breathing, and swelling of your face, lips, tongue, or throat.
Pregnancy: Azathioprine can harm an unborn baby. Therefore, it’s contraindicated in pregnancy unless the potential benefit justifies the potential risk to the fetus.
Severe liver disease: As Azathioprine can potentially cause liver damage, it’s contraindicated in people with severe liver disease.

Drug to Drug Interactions

Several medications can interact with Azathioprine. Here are some of them:
Allopurinol (Zyloprim): This medication can increase the effects of Azathioprine, potentially leading to harmful side effects.
Warfarin (Coumadin): Azathioprine can increase the effects of Warfarin, potentially increasing the risk of bleeding.
ACE inhibitors, such as Lisinopril (Prinivil, Zestril): These can increase the risk of blood disorders when taken with Azathioprine.

Azathioprine in Pregnancy

Azathioprine may cause harm to an unborn baby and is generally not recommended for use during pregnancy. If you are pregnant or plan to become pregnant, discuss the risks and benefits with your doctor.

Azathioprine while Breastfeeding

Azathioprine passes into breast milk and may have undesirable effects on a nursing infant. Therefore, breastfeeding while using this drug is not recommended.

Estimated Cost of Medication

The cost of Azathioprine can vary depending on the pharmacy and location. As of the writing of this article, the estimated cost of a 30-day supply of 50 mg Azathioprine tablets without insurance and with a GoodRx coupon is approximately $25-$35. Remember, these prices are estimates and can change based on various factors.

Brief Legal Disclaimer

This article is for informational purposes only and not intended as medical advice. Always consult a healthcare professional for diagnosis and treatment. Reliance on the information provided here is at your own risk.

Brief Legal Disclaimer: This article is for informational purposes only and not intended as medical advice. Always consult a healthcare professional for diagnosis and treatment. Reliance on the information provided here is at your own risk.