Sulfasalazine showed no clear difference in serious adverse events compared with placebo (moderate certainty).
Sulfasalazine probably leads to higher total number of withdrawals due to adverse events compared with placebo (moderate certainty).
Oral 5‐aminosalicylic acid showed no clear difference in adverse event compared with sulfasalazine (moderate certainty).
It is very uncertain whether azathioprine or 6‐mercaptopurine changes adverse events compared with mesalazine or sulfasalazine (very low certainty).
The review found no eligible studies for this question.
It is very uncertain whether azathioprine or 6‐mercaptopurine changes serious adverse events compared with mesalazine or sulfasalazine (very low certainty).
Oral 5‐aminosalicylic acid showed no clear difference in withdrawal due to adverse event compared with sulfasalazine (moderate certainty).
It is very uncertain whether azathioprine or 6‐mercaptopurine changes withdrawals due to adverse events compared with mesalazine or sulfasalazine (very low certainty).