Tools for Practice

#182 Chew on This: Why gum is good for your post-operative bum

Does chewing gum after surgery improve bowel function?

Chewing gum in post abdominal surgery patients shortens time to first flatus (by 10 hours), time to first bowel motion (by ~1/2 day), and length of hospital stay (by~0.7 days). For every five patients treated, one fewer will develop ileus. Chewing gum in non-post-surgical constipation has not been studied. 

CFPCLearn Logo

Reading Tools for Practice Article can earn you MainPro+ Credits

Join Now

Already a CFPCLearn Member? Log in

  • Use in colorectal, gynecological, and other abdominal surgeries: 
    • Systematic review of 81 Randomized Controlled Trials (RCTs) comparing post-operative chewing gum to any intervention (9,072 patients):1  
      • Chewing gum resulted in statistically significant decreases in:  
        • Time to first flatus (TFF)B10 hours. 
        • Time to first bowel motion (TFBM)B13 hours. 
        • Length of stay (LOS): B0.7 days. 
      • Other post-operative complications (like nausea/vomiting) similar.1 
      • Limitations: Majority small studies, open-label, patients with previous abdominal surgery or intra-operative complications often excluded. 
    • Recent high quality RCT (after systematic review)112 Dutch patients, open colorectal surgery randomized to chewing gum or placebo dermal patch.2 Chewing gum significantly:  
      • Improved number of patients with first bowel motion within three days: 85% versus 57%: Number Needed to Treat (NNT)=4. 
      • Decreased ileus at Day 5 (27% versus 48%, NNT=5) and LOS (9.5 versus 14 days).  
  • Use with Enhanced Recovery after Surgery (ERAS) programs: Four RCTs (571 patients) post-colorectal surgery, decreased TFBM by 21 hours, but no significant difference in TFF or LOS.1  
    • LimitationHigh quality and largest study (>72% of above patients) measured outcomes in days (not hours).3 
  • Cesarean sections:4 Seventeen RCTs (3,149 patients), chewing gum versus usual care significantly decreased: TFF (7 hours), TFBM (9 hours), and hospital LOS (9 hours).  
  • Timing of intervention, type, frequency, and duration of gum use varied across studies.1,4 Commonly, patients chewed gum 3-4 times per day, starting 2-3 hours after surgery.  
  • ERAS interventions, including early feeding, venous thromboembolism, antibiotic prophylaxis, laparoscopic surgery when appropriate, early mobilization, adequate analgesia, and anti-emetics5 reduce post-operative colorectal surgery complications, hospitalizations (~1-3 days),6-8 and health care costs.9 
  • Chewing gum for idiopathic constipation has not been studied.  

Latest Tools for Practice

#341 Forget about it? Statins and the risk of dementia (Free)

Do statins negatively affect cognition, memory, or dementia?
Read 0.25 credits available

#340 Crying babies: Can proton pump inhibitors help? (Free)

In infants (≤1year) with crying/irritability attributed to feeds, do proton pump inhibitors (PPIs) improve symptoms over placebo without additional harms?
Read 0.25 credits available

#339 Is acetaminophen under pressure?

Does regular use of acetaminophen increase blood pressure?
Read 0.25 credits available

This content is certified for MainPro+ Credits, log in to access


  • Jennifer Ng
  • Michael R Kolber BSc MD CCFP MSc

1. Short V, Herbert G, Perry R, et al. Cochrane Database Syst Rev. 2015; 2:CD006506.

2. van den Heijkant TC, Costes LMM, van der Lee DGC, et al. Br J Surg. 2015; 102:202-11.

3. Atkinson C, Penfold CM, Ness AR, et al. Br J Surg. 2016; 103:962-70.

4. Pereira Gomes Morais E, Riera R, Porfírio GJM, et al. Cochrane Database Syst Rev. 2016; 10:CD011562.

5. Kehlet H. Lancet. 2008; 371:791-3.

6. Spanjersberg WR, Reurings J, Keus F, et al. Cochrane Database Syst Rev. 2011;2:CD007635.

7. Charoenkwan K, Matovinovic E. Cochrane Database Syst Rev. 2014;12:CD004508.

8. Paton F, Chambers D, Wilson P, et al. BMJ Open. 2014; 4:e005015.

9. Nelson G, Kiyang LN, Crumley E, et al. World J Surg. 2016; 40:1092-1103.

Authors do not have any conflicts of interest to declare.