Does sermorelin cause steatorrhea (excess fat in stool)?

Sermorelin and Steatorrhea: Clinical Evidence and Implications

Based on the available medical evidence, sermorelin does not cause steatorrhea (excess fat in stool). There is no documented association between sermorelin therapy and fat malabsorption in the medical literature.

Understanding Sermorelin

Sermorelin is a 29-amino acid analogue of human growth hormone-releasing hormone (GHRH) that specifically stimulates growth hormone secretion from the anterior pituitary 1. It has been used for:

• Diagnosis of growth hormone deficiency when administered as an intravenous dose of 1 μg/kg bodyweight 1
• Treatment of some prepubertal children with idiopathic growth hormone deficiency at a subcutaneous dose of 30 μg/kg bodyweight 1
• More recently, tesamorelin (another GHRH analogue) has been approved for reducing excess abdominal fat in HIV-infected patients with lipodystrophy 2

Common Side Effects of Sermorelin

The documented side effects of sermorelin do not include steatorrhea or other gastrointestinal fat malabsorption issues:

• Transient facial flushing 1
• Pain at injection site 1

Understanding Steatorrhea

Steatorrhea is characterized by:

• Bulky, pale, malodorous, and floating stools due to excess fat content 3
• Formally defined as >7% of ingested fat present in stool or a coefficient of fat absorption <93% 3
• Associated symptoms including flatulence, bloating, dyspepsia, urgency, and cramping abdominal pain 3
• Often accompanied by weight loss and deficiencies in fat-soluble vitamins (A, D, E, K) 3

Common Causes of Steatorrhea

Steatorrhea is typically caused by:

1. Pancreatic exocrine insufficiency (EPI) - the most common cause of severe steatorrhea 3
2. Small bowel disorders - including celiac disease, Crohn's disease, and small bowel bacterial overgrowth 3
3. Surgical causes - including small bowel resections and bariatric surgery 3
4. Bile acid malabsorption - contributing to fat maldigestion 3, 4
5. Medication effects - notably, orlistat (Xenical/Alli) is a weight loss medication that intentionally causes steatorrhea by inhibiting pancreatic and gastric lipases, blocking absorption of about 30% of ingested fat 5, 6

Diagnostic Approach to Steatorrhea

If a patient on sermorelin reports symptoms suggestive of steatorrhea, appropriate evaluation should include:

• Fecal elastase-1 (FE-1) testing - the most commonly used indirect pancreatic function test 3

  • FE-1 <200 mg/g of stool is considered abnormal
  • FE-1 <100 mg/g is more consistent with EPI
  • FE-1 <50 mg/g is most reliable for severe EPI

• Quantitative fecal fat measurement - requires a diet of known fat content ingested over 5 days with stool collection during the final 3 days 3

  • Fecal fat exceeding 13 g/day (47 mmol/day) is considered severe steatorrhea 3

Clinical Implications

If a patient on sermorelin therapy develops steatorrhea:

• The cause is likely unrelated to sermorelin and should prompt investigation for other etiologies 3
• Consider common causes such as pancreatic insufficiency, celiac disease, or small bowel bacterial overgrowth 3
• Review concurrent medications, particularly those known to affect fat digestion or absorption, such as orlistat 5, 6
• Evaluate for surgical history that might predispose to malabsorption, such as ileal resection 4, 7

Conclusion

There is no evidence in the medical literature linking sermorelin to steatorrhea or fat malabsorption. If steatorrhea occurs in a patient taking sermorelin, clinicians should investigate other more common causes rather than attributing it to the medication.