Stopping smoking can cause constipation

Setting  Constipation is mentioned occasionally as a possible tobacco withdrawal symptom, but no systematic data have been published on this issue.

Design  Smokers’ clinic patients provided ratings of their level of constipation on three occasions prior to their quit date, and then weekly after they stopped smoking. The total of 1067 participants maintained at least 1 week of continuous abstinence and provided usable data.

Findings  The three precessation ratings of constipation were stable. After cessation of smoking, the ratings increased significantly (P < 0.01). In 514 patients who maintained continuous abstinence for 4 weeks and provided complete data, constipation peaked at 2 weeks but remained elevated over the whole period. The net proportion of patients affected was 17%, including 9% who were symptom-free at baseline and became very or extremely constipated. In patients on nicotine replacement the increase in constipation, although significant, was less than in patients on bupropion.

Conclusions  Clinicians treating smokers need to be aware of a possibility that one in six quitters develop constipation, and that for about one in 11 the problem can be severe. Descriptions of tobacco withdrawal syndrome should include constipation.