Can a patient with Behçet's disease, currently taking Imuran (Azathioprine), safely continue taking Camrese Lo (Levonorgestrel and Ethinyl Estradiol)?

Can a Behçet's Patient on Imuran Continue Taking Camrese Lo?

Yes, a patient with Behçet's disease taking Imuran (azathioprine) can safely continue Camrese Lo (levonorgestrel/ethinyl estradiol), as there are no known drug interactions between azathioprine and combined oral contraceptives, and the primary concern with hormonal contraception in this population relates to thrombotic risk rather than immunosuppressive therapy compatibility.

Key Considerations for Safety

No Direct Drug Interaction

• Azathioprine does not interact pharmacologically with levonorgestrel or ethinyl estradiol 1
• The dermatology guidelines for azathioprine prescribing do not list hormonal contraceptives as contraindicated medications, with the only significant drug interaction being allopurinol (which causes severe myelosuppression) 1

Thrombotic Risk Assessment is Critical

The decision to continue Camrese Lo depends primarily on the patient's thrombotic risk profile, not the azathioprine use:

Favorable factors for continuing Camrese Lo:

• No history of thrombotic events (deep vein thrombosis, pulmonary embolism, stroke) 1
• No antiphospholipid antibodies 1, 2
• Stable Behçet's disease without active vascular involvement 3

Contraindications to continuing Camrese Lo:

• History of venous or arterial thrombosis 1
• Positive antiphospholipid antibodies (strongly contraindicated) 1, 2
• Active vascular Behçet's disease with arterial or venous involvement 3
• Prolonged immobilization 1

Behçet's Disease-Specific Concerns

• Patients with Behçet's disease have an increased cardiovascular risk (HR 1.72 for myocardial infarction, HR 1.65 for stroke) compared to controls 3
• This elevated baseline thrombotic risk must be weighed against the additional thrombotic risk from combined hormonal contraceptives 3
• Camrese Lo contains 20 mcg ethinyl estradiol, which is a lower-dose formulation that may carry slightly less thrombotic risk than higher-dose preparations 1

Clinical Algorithm for Decision-Making

Step 1: Assess thrombotic history

• If any history of thrombosis → discontinue Camrese Lo immediately and switch to progestin-only method or copper IUD 1, 2

Step 2: Check antiphospholipid antibody status

• If positive aPL → discontinue Camrese Lo and use levonorgestrel IUD or progestin-only pill 1, 2
• If negative or unknown → proceed to Step 3

Step 3: Evaluate Behçet's disease activity

• If active vascular involvement (arterial aneurysms, venous thrombosis, major vessel disease) → discontinue Camrese Lo and use alternative contraception 3
• If mucocutaneous or ocular disease only without vascular involvement → may continue with close monitoring 1

Step 4: Consider alternative contraception if any concerns

• Levonorgestrel IUD is highly effective and avoids systemic estrogen exposure 1, 2
• Progestin-only pills are acceptable alternatives 1
• Avoid depot medroxyprogesterone acetate (DMPA) due to potential thrombogenic effects 1, 4

Azathioprine-Specific Monitoring Remains Unchanged

• Continue routine monitoring for azathioprine toxicity (complete blood count, liver function tests) regardless of contraceptive choice 1
• Azathioprine has demonstrated efficacy in Behçet's disease, particularly for preventing ocular complications and reducing extraocular manifestations 1, 5
• The combination of azathioprine with corticosteroids is standard therapy for severe Behçet's disease 1, 6

Common Pitfalls to Avoid

• Do not assume all patients with Behçet's disease have contraindications to estrogen-containing contraceptives - the decision is individualized based on thrombotic risk factors 1, 3
• Do not overlook antiphospholipid antibody testing - this is an absolute contraindication to combined hormonal contraceptives that may be present in Behçet's patients 1, 2
• Do not confuse the safety of azathioprine with contraceptives versus the independent thrombotic risks - these are separate considerations 1
• Remember that adequate contraception is essential during azathioprine therapy, as azathioprine is contraindicated in pregnancy except when benefits outweigh risks 1