Jennifer Nolan (Pharmacist John Hunter Hospital)
Principles of Management:
1. Identification and treatment of cause.
2. Replacement of water and electrolyte losses (initially intravenously).
3. Restriction of oral hypotonic fluids and encouragement of glucose/electrolyte fluids.
5. Pharmacological management.
5. Nutritional support if needed.
1. Identify causes
Exclude Intra-abdominal sepsis, Intermittent bowel obstruction, Enteritis eg. Clostridium difficile, residual or recurrent disease in the remaining bowel.
Consider medications such as abrupt cessation of opioids or anticholinergics or administration of prokinetics
2. Initial Management
Rehydrate with intravenous fluids: Normal Saline (or Hartmann’s Solution with appropriate Potassium supplementation)
Commence loperamide 4mg QDS
STRICT fluid balance
Daily UEC, magnesium levels
3. Oral Rehydration
The jejunal luminal sodium concentration = 90 – 100mmol/L. Hypotonic fluids have an osmolality of <90mmol/L. They produce a net efflux of sodium from plasma into bowel lumen until concentration of ~100mmol/L is reached. This can increase stomal sodium losses and therefore stomal output. Restriction of oral hypotonic fluids should be considered initially.
The administration of oral hypertonic fluids (>90mmol/L) may be of additional benefit (particularly after discharge form hospital) such as Gastrolyte (Double Strength) 2 sachets per 200mL of water.
4. Pharmacological Management
a) Reduce motility with anti-motility drugs (essentially opiates). Activate opioid receptors in gut lumen reduce peristalsis and increase fluid absorption
i) Loperamide. This is the mainstay of treatment and should be escalated to the appropriate dose. It is most effective and has the least systemic side effects.
4mg QDS initially, may increase by 2mg QDS up to 16mg QDS. Open capsules and give contents half an hour before meals and at bedtime
Other options include:
ii) Codeine (if loperamide 16mg QDS is ineffective, add codeine30 – 60 mg qds half an hour before meals). Caution in renal/hepatic impairment, elderly, respiratory depression, CNS depression, breastfeeding, etc. May cause delayed biliary tract emptying decreased bile output increased faecal fat content.
iii) Lomotil (Diphenoxylate + atropine). May be considered 1tablet bd, increasing to 2 tabs up to QDS. Diphenoxylate structurally related to pethidine – atropine added to discourage misuse. Atropine is an anticholinergic which may itself exhibit anti-motility effects, but unlikely at this dose.
b) Thicken with fibre (Metamucil/Benefibre)
c) Prevent losses with rehydration therapy
d) Proton Pump Inhibitors. Bowel resection or inflammation can result in gastric acid hypersecretion. Omeprazole, Lansoprazole etc may require higher doses.
e) AntiSecretory Drugs. Somatostatin analogues (Octreotide or Long Acting Analogues). These inhibit secretion of a vast array of GI Hormones such as Serotonin, GEP Peptides, Gastrin, VIP, Insulin, Glucagon, Secretin, Motilin, Pancreatic Polypeptide, Growth Hormone.
Initiate Octreotide 100mcg tds SubCut, but this is painful. Long acting analogs such as Lanreotide should be commenced if Octreotide proves to be effective.