Mesalamine seems to benefit women more than men. All mesalamine preparations, including sulfasalazine, appear to be safe for children and for women who are pregnant or nursing.
Sulfasalazine. Sulfasalazine (Azulfidine) is the standard mesalamine preparation. Sulfasalazine is known as a prodrug because it becomes an active drug when it breaks down by intestinal bacteria. It is broken down into two components: mesalamine and sulfapyridine:
- Mesalamine, the active component, blocks the inflammatory process.
- Sulfapyridine (a sulfa antibiotic) plays no role in treating the disease, but it does prevent mesalamine from being absorbed until it reaches the colon.
For patients with mild-to-moderate Crohn's disease, sulfasalazine and other mesalamine preparations and formulations are generally most useful in combination with steroids and when the disease is limited to the colon. A syrup form of sulfasalazine is available for children.
Side effects of sulfasalazine differ depending on the specific component.
- Mesalamine Component. Mesalamine has a chemical structure similar to aspirin. Therefore, people allergic to aspirin should not take any of the 5-ASA drugs or preparations. Mesalamine itself has few side effects and is considered safe to take during pregnancy. One of the most common side effects is diarrhea, which varies depending on the preparation. For example, olsalazine poses a risk for diarrhea, which may be minimized by starting out with lower doses and taking the medication with meals. Other side effects of all oral forms of mesalamine are skin disorders, nausea, cramps, itchiness, anxiety attacks, and inflammation of other organs. Oral mesalamine, particularly Asacol, may slightly increase the risk for kidney damage. (Olsalazine has a lesser effect on the kidneys.)
- Sulfapyridine, the Sulfa Component. The sulfa component is responsible for most of sulfasalazine's adverse side effects, which are experienced by up to 30% of patients taking this drug. Common side effects include allergic reactions, heartburn, headache, loss of appetite, abdominal discomfort, dizziness, anemia, fever, and rashes. The sulfa component may temporarily lower sperm count in men and can turn urine a bright orange-yellow color. Rare but serious side effects include a lupus-like disorder, pancreatitis, liver damage, and blood disorders, such as hemolytic anemia. Blood counts should be performed regularly, particularly during the first few weeks of treatment. Sulfasalazine completely inhibits the absorption of folic acid and patients should take supplements of this important B vitamin. This is critical during pregnancy. As with most major drugs for IBD, withdrawal of sulfasalazine when the disease is still active can trigger a severe relapse.
Previous Section
