进食生冷食物或某些药物如水杨酸盐类、磺胺、某些抗生素等；
1·Hind of profess to convinced is easy decompose inside bowel reach 5 - amino salicylic acid for sulphanilamide pyridine, to colonic wall the organization has affinity, have antiphlogistic effect.
口服后易在肠内分解为磺胺吡啶及5 -氨基水杨酸，对结肠壁组织有亲合力，起到消炎作用。