Azathioprine Medication: Uses, Dosage, Side Effects & Interactions

Summary of Key Points

Azathioprine is an immunosuppressive medication commonly prescribed for autoimmune conditions such as rheumatoid arthritis, Crohn’s disease, and lupus. It works by weakening the immune system to prevent it from attacking healthy tissues. Due to the potential for side effects, it is important to follow prescribed dosages carefully and undergo regular monitoring. Always consult your healthcare provider before starting or adjusting your dose. If you need personalized advice, you can easily schedule a telemedicine appointment with one of our providers.

Names of Azathioprine Medication

US Brand Name: Imuran

Generic Name: Azathioprine

The generic name refers to the active ingredient, while the brand name is assigned by the manufacturer. In this case, Azathioprine is the generic name.

Pharmacologic Category of Azathioprine

Immunosuppressant

Antimetabolite

Azathioprine Dosage Guidelines

Azathioprine is used to manage a variety of autoimmune conditions. The dosage will vary depending on the specific condition being treated. Always follow your doctor’s instructions and consult them before making any changes to your dosage. If you have any questions, you can also speak with one of our telemedicine providers for further guidance.

Azathioprine Dosage for Rheumatoid Arthritis

Initial dose: 1 mg/kg/day orally, once daily

Maintenance dose: 1-2.5 mg/kg/day

Duration: Long-term, based on response and tolerance

Azathioprine Dosage for Crohn’s Disease

Initial dose: 2-2.5 mg/kg/day orally, once daily

Maintenance dose: Same as initial

Duration: Long-term, based on response and tolerance

Azathioprine Dosage for Ulcerative Colitis

Initial dose: 1.5-2.5 mg/kg/day orally, once daily

Maintenance dose: Same as initial

Duration: Long-term, based on response and tolerance

Azathioprine Dosage for Systemic Lupus Erythematosus

Initial dose: 1-2 mg/kg/day orally, once daily

Maintenance dose: 1-2.5 mg/kg/day

Duration: Long-term, based on response and tolerance

Azathioprine Dosage for Autoimmune Hepatitis

Initial dose: 1-2 mg/kg/day orally, once daily

Maintenance dose: 1-2 mg/kg/day

Duration: Long-term, based on response and tolerance

Azathioprine Dosage for Dermatomyositis

Initial dose: 1-3 mg/kg/day orally, once daily

Maintenance dose: Same as initial

Duration: Long-term, based on response and tolerance

Azathioprine Dosage for Multiple Sclerosis

Initial dose: 1-3 mg/kg/day orally, once daily

Maintenance dose: Same as initial

Duration: Long-term, based on response and tolerance

Azathioprine Dosage for Vasculitis

Initial dose: 1-3 mg/kg/day orally, once daily

Maintenance dose: Same as initial

Duration: Long-term, based on response and tolerance

Azathioprine Dosage for Psoriasis

Initial dose: 1-3 mg/kg/day orally, once daily

Maintenance dose: Same as initial

Duration: Long-term, based on response and tolerance

Azathioprine Dosage for Myasthenia Gravis

Initial dose: 1-3 mg/kg/day orally, once daily

Maintenance dose: Same as initial

Duration: Long-term, based on response and tolerance

Azathioprine Dosage Forms and Strengths

Tablet: 50 mg

Oral suspension: 10 mg/mL

Azathioprine Administration Instructions

Take Azathioprine exactly as prescribed by your doctor, typically once daily, with or without food. If you experience stomach discomfort, taking it with food may help alleviate this. Do not crush or chew the tablets. If you miss a dose, take it as soon as you remember, unless it is almost time for your next dose. In that case, skip the missed dose and continue with your regular schedule. Always consult your healthcare provider for specific instructions, and feel free to reach out to one of our telemedicine providers if you have any questions or concerns.

Azathioprine Contraindications

A contraindication is a specific situation where a medication should not be used because it may cause harm. Several conditions make the use of Azathioprine inadvisable.

Allergy to Azathioprine or Mercaptopurine: If you have a known allergy to Azathioprine or its metabolite, mercaptopurine, you should avoid this medication. Allergic reactions can be serious, with symptoms such as rash, difficulty breathing, or swelling.

Severe liver disease: Azathioprine is metabolized by the liver. If you have severe liver disease, your body may not process the drug properly, which can lead to toxicity.

Pregnancy (in certain cases): Azathioprine may pose risks to a developing fetus, particularly during the first trimester. If you are pregnant or planning to become pregnant, discuss the potential benefits and risks with your healthcare provider.

Active infections: Since Azathioprine suppresses the immune system, it can make it harder for your body to fight infections. If you have an active infection, taking Azathioprine could worsen your condition.

Pancreatitis: Azathioprine can increase the risk of pancreatitis (inflammation of the pancreas), especially in individuals with a history of this condition.

Azathioprine Drug Interactions

Azathioprine can interact with other medications, potentially increasing the risk of side effects or reducing the effectiveness of treatment. Be sure to inform your healthcare provider about all medications you are taking, including over-the-counter drugs, supplements, and herbal products.

Allopurinol (Zyloprim): Used to treat gout, Allopurinol can increase Azathioprine levels in your body, leading to toxicity. Your doctor may need to adjust your dose if you are taking both medications.

Warfarin (Coumadin): Azathioprine can reduce the effectiveness of warfarin, a blood thinner, which may increase the risk of blood clots. Close monitoring is required.

Aminosalicylates (e.g., Mesalamine, Sulfasalazine): These medications, often used for inflammatory bowel disease, can increase the risk of bone marrow suppression when taken with Azathioprine.

ACE inhibitors (e.g., Lisinopril, Enalapril): These blood pressure medications can increase the risk of anemia and low white blood cell counts when combined with Azathioprine.

Ribavirin: This antiviral drug can increase the risk of Azathioprine-related toxicity, particularly affecting the bone marrow.

Azathioprine and Pregnancy: Is It Safe?

Is it safe to take Azathioprine during pregnancy?

Azathioprine is classified as a Category D medication by the FDA, indicating that there is evidence of potential risk to the fetus. However, in certain situations, the benefits of taking Azathioprine may outweigh the risks, particularly if you have a serious autoimmune condition that requires ongoing treatment. If you are pregnant or planning to become pregnant, it’s crucial to have an open discussion with your healthcare provider. They may adjust your dosage or closely monitor your pregnancy to ensure the best possible outcomes for both you and your baby.

Azathioprine and Breastfeeding: What You Need to Know

Is it safe to take Azathioprine while breastfeeding?

Azathioprine can pass into breast milk in small amounts. While some studies suggest it may be safe to use during breastfeeding, especially at lower doses, there remains a potential risk to the infant, including possible suppression of the immune system. If you are breastfeeding, it’s important to consult your healthcare provider to determine whether Azathioprine is the right option for you. In some cases, alternative medications may be recommended, or you may be advised to avoid breastfeeding while taking Azathioprine.

Azathioprine Cost and Availability

The estimated cost of a 30-day supply of Azathioprine (50 mg tablets) without insurance typically ranges from $15 to $30 when using a GoodRX coupon. Prices can vary depending on the pharmacy and your location. Be sure to explore available discounts and coupons to help reduce the cost of your prescription.

Azathioprine Alternatives for Autoimmune Conditions

If Azathioprine is not suitable for you, there are alternative treatments available for the conditions it is commonly prescribed for. Always consult with your healthcare provider before making any changes to your treatment plan. You can also schedule a telemedicine appointment with one of our providers to discuss your options.

1. Rheumatoid arthritis: Alternatives include methotrexate, leflunomide, or biologics such as adalimumab (Humira). Lifestyle changes, including regular exercise and a balanced diet, can also help manage symptoms.
2. Crohn’s disease: Biologics like infliximab (Remicade) or adalimumab (Humira) are commonly used. Dietary adjustments, such as avoiding trigger foods, may also help control symptoms.
3. Ulcerative colitis: Mesalamine (Asacol) or biologics like vedolizumab (Entyvio) are potential alternatives. Dietary modifications and stress management techniques can also be beneficial.
4. Systemic lupus erythematosus: Hydroxychloroquine (Plaquenil) or corticosteroids are frequently prescribed. Regular exercise and sun protection are important lifestyle considerations.
5. Autoimmune hepatitis: Prednisone or mycophenolate mofetil (CellCept) are alternatives. Limiting alcohol intake and following a liver-friendly diet can also support liver health.
6. Dermatomyositis: Methotrexate or intravenous immunoglobulin (IVIG) are alternatives. Physical therapy is often recommended to improve muscle strength and function.
7. Multiple sclerosis: Disease-modifying therapies such as interferon beta or glatiramer acetate (Copaxone) are alternatives. Regular exercise and a nutritious diet may also help manage symptoms.
8. Vasculitis: Corticosteroids or rituximab (Rituxan) are frequently used. Maintaining a healthy lifestyle and managing stress can help reduce flare-ups.
9. Psoriasis: Biologics like etanercept (Enbrel) or ustekinumab (Stelara) are alternatives. Regular moisturizing and avoiding triggers such as stress and certain foods can help manage symptoms.
10. Myasthenia gravis: Pyridostigmine (Mestinon) or corticosteroids are commonly prescribed. Regular physical activity and stress management can also help improve symptoms.

Recent Updates on Azathioprine Research

Recent studies have focused on the long-term safety of Azathioprine, particularly in patients with autoimmune diseases. Some research suggests that while Azathioprine is effective in managing chronic conditions, prolonged use may increase the risk of certain cancers, such as skin cancer and lymphoma. Ongoing studies are exploring strategies to minimize these risks, such as using lower doses or combining Azathioprine with other medications to reduce the need for higher doses.

Additionally, researchers are investigating personalized medicine approaches, where genetic testing could help predict how well a patient will respond to Azathioprine or whether they are at a higher risk for side effects. This could lead to more individualized treatment plans and improved outcomes for patients.

If you have concerns about your treatment with Azathioprine or would like to learn more about the latest research, schedule a telemedicine appointment with one of our providers today.

James Kingsley

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