Constipation is a common cause of ED presentation – with nausea, vomiting, abdominal pain and cramping – sometimes with impaction and obstipation. Constipation is most frequently opioid-induced: opioids cause constipation by decreased motility and decreased mucus secretion in the large bowel.
- A digital exam to see if there is stool in the rectal vault
- Disimpaction –use a glycerin suppository one hour in advance to soften the stool
- High enemas (soap suds)
- Osmotic carthartics: polyethylene glycol (GoLytely), magnesium citrate (Citro-Dan)
- Start with Sennosides (2 tablets or 15 mL at bedtime); or Bisacodyl (1-2 tablets nightly); increase each by 50% each night ’til effective; high doses may be required to overcome the opioid-induced loss of motility.
- PEG 3350 (1-2 sachets to start); or Lactulose 30 mL in the morning; double the dose daily ’til effective; or MagCitrate.
- Fibre and bulk-forming supplements (©Metamucil) are of little benefit in opioid constipation or patients with advanced disease.