CCoPE
Date: 2007-05-01

Question:
I have rheumatoid arthiritis. I am currently taking 25 Mg of methotrexate sod (by injection) and 50 mg of Enbrel (also by injection) per week. I am also taking 5 mg of Folic Acid, a prenatal vitamin with 1 mg of Folic acid, and calcium supplements everyday. I am planning on getting pregnant this summer. My Rheumatologist has advised me to stop methotrexate and Enbrel one month prior to when I want to conceive. He also said that I can continue on with the Folic Acid (5 mg/day) throughout the pregnancy. My question is - can a person obtain too much folic acid (is that possible)? Do I continue taking the prenatal vitamin if I continue to take the prescription folic acid? Is one month sufficient time to stop the Enbrel and Methotrexate prior to conception?

Answer:

Consult your physician. The following information should not replace the assessment and advice you have been receiving from your physician (cancer specialist, obstetrician, or any other healthcare provider). It is offered for your information only.

Methotrexate is a structural analogue of folic acid and because of its short half-life, it will not stay in the body for more than a few days. There have been reports of women who have discontinued methotrexate prior to conception and they delivered healthy infants without birth defects (Briggs 2005). Several sources have suggested that women wait at least 12 weeks after stopping therapy before conceiving (Ann Int Med 1977;86:1999). It is sensible for you to take 5mg of folic acid, as it gives better protection against neural tube defects especially because you received an antifolate drug (methotrexate).

With regards to Enbrel, there are no current recommendations about how long one should not be taking it before trying to conceive. However, due to the longer half-life of the drug it would take approximately one month for the drug to be removed from the body (Hale 2006).