Should You Take Folic Acid With Sulfa Drugs?

Sulfa antibiotics are used to treat a variety of bacterial infections, including ear infections, Pneumocystis carinii pneumonia, urinary tract infections and other infections caused by bacteria such as E. coli, streptococcus pneumoniae or Klebsiella, among others. Certain anti-inflammatory drugs used to treat rheumatoid disorders as well as inflammatory bowel disease also contain sulfa, such as sulfasalazine. Sulfa-based medications can cause or worsen folic acid deficiency under some circumstances. Your doctor may prescribe folic acid supplements, also called folate, when you take sulfa-based drugs, particularly if you take them for long time periods.

Interactions

Sulfa drugs interfere with the absorption of folate through the intestines and can also interfere with the metabolism of folic acid. Decreased absorption of folate can lead to folate deficiency. Deficiency is particularly likely to occur in people taking sulfasalazine to treat diseases that also interfere with folate absorption such as inflammatory bowel disease.

Pregnancy Effects

Folic acid is one of the B-complex vitamins. One important purpose of folic acid is to prevent neural tube defects such as spina bifida in pregnancy; an adequate amount of folic acid can reduce neural tube defects by 50 to 75 percent, according to the Centers for Disease Control and Prevention. Large amounts of folic acid are necessary for the rapid cell division that occurs in the fetus in early pregnancy. While prenatal vitamins contain folic acid, you may need a larger than average amount if you're taking a sulfa drug. Follow your doctor's recommendations on whether to take more folic acid than is supplied in the average prenatal vitamin, which is normally between 800 micrograms to 1 mg in the U.S., according to NetWellness.

Signs of Folic Acid Deficiency

Folate helps make new red blood cells. Folate deficiency can lead to folate deficiency anemia, also called megaloblastic anemia, so named because the red blood cells are larger than normal. This type of anemia causes fatigue, shortness of breath, dizziness, a rapid heartbeat and a red, shiny, irritated tongue. Indigestion, decreased ability to taste foods, indigestion and diarrhea may also occur.

Considerations

Do not take folic acid supplements and sulfa medication at the same time. The University of North Carolina Chapel Hill recommends taking a 1-mg-per-day folic acid supplement if you take a sulfa-containing drug long term to treat a chronic condition such as IBS. Your doctor may also suggest stopping sulfa medications if you're planning on becoming pregnant or are pregnant.