How long before conception should a patient stop taking their medication?

Medication Discontinuation Before Attempting Conception

Patients should discontinue medications before attempting conception based on specific timeframes determined by the medication's half-life and potential teratogenic effects: antifibrinolytics should be stopped several days before conception, anabolic steroids 2 months before, methotrexate 3 months before, and mycophenolate products at least 6 weeks before conception. 1

Medication-Specific Discontinuation Timeframes

Medications Requiring Longer Discontinuation Periods

• Methotrexate: Stop 3 months before conception 1

  • Strong recommendation based on potential teratogenic effects
  • Associated with 3.4-fold increased risk of cardiovascular defects and 2.6-fold increased risk of oral clefts 1
  • Pharmacokinetic data shows median half-life for elimination is 1.2-4.3 weeks 1

• Anabolic Steroids (AAs): Stop 2 months before conception 1

  • Mean half-life for danazol is approximately 9.44 hours
  • Negative pregnancy test required before starting AA therapy
  • Risk of abnormalities of sexual differentiation in the fetus if pregnancy occurs while taking AAs

• Mycophenolate Products (mycophenolate mofetil, mycophenolate sodium): Stop at least 6 weeks before conception 1

  • Contraindicated in pregnancy due to high risk of congenital malformations and spontaneous abortions
  • FDA issued Risk Evaluation and Mitigation Strategies program for MPAs 1

Medications Requiring Shorter Discontinuation Periods

• Antifibrinolytic Agents (e.g., tranexamic acid): Stop several days before conception 1

  • Eliminated by rapid renal clearance (half-life of 2-8 hours)

• Ecallantide, Icatibant acetate, and rhC1INH: Stop 1 week before conception 1

  • Short half-lives (ecallantide: 2.0 hours; icatibant acetate: 1-2 hours; rhC1INH: 3 hours)

Medications That Can Be Continued

• pdhC1INH concentrate: Can continue during conception, pregnancy, and delivery 1

Special Considerations

Risk Assessment and Monitoring

• Document a negative pregnancy test within 1 week of starting high-risk medications 1
• Ensure adequate contraception while on teratogenic medications 1, 2
• If conception occurs while taking methotrexate, discontinue immediately and refer for obstetric counseling 1

Medication Switching

• When switching medications before conception, allow adequate time to ensure sustained remission before attempting conception 1
• Consider the risk of disease flare when discontinuing medications 1

Disease-Specific Considerations

• For patients with inflammatory bowel disease, sustained remission for at least 3 months before conception is recommended 1
• For patients with hereditary angioedema, pdhC1INH is the treatment of choice during conception and pregnancy 1
• For patients with autoimmune hepatitis, azathioprine and 6-mercaptopurine are considered safe in pregnancy and can be continued 1

By following these medication-specific discontinuation timeframes, patients can minimize potential risks to maternal and fetal health while maintaining disease control when attempting conception.