The Long-Acting Somatostatin Analogue SMS 201-995 Causes Malabsorption

Abstract

Somatostatin and its long-acting analogue SMS 201–995 (Sandostatin^±) have been suspected of causing steatorrhoea. The aim of this study was to examine the effect of SMS 201–995 on fat assimilation in healthy subjects, using ¹⁴C–triolein and ³H-oleic acid as tracers of dietary triglycerides and free fatty acids, respectively, and ⁵¹CrCl₃ as non-absorbable marker. Six healthy male volunteers participated in the double-blinded, randomized, crossover study. In each test period either 1 ml of SMS 201–995, containing 200 μg, or 1 ml of isotone saline was given subcutaneously three times within 16 h. Faeces were collected for 3 days, every stool separately. The faecal ¹⁴C-triolein and ³H-oleic acid excretion was calculated from two aliquots of faeces. In addition, the mean daily faecal fat excretion was estimated. When placebo was given, the median ¹⁴C-triolein excretion was 1% (range, 0.9–1.6%), the median ³H-oleic acid excretion was 5% (range, 3–10%), and the daily faecal fat excretion was 4g/ day (range, l–6g/day), all within normal limits. When SMS 201–995 was given, the faecal ¹⁴C-triolein excretion increased to a median of 75% (range, 43–119%), the ³H-oleic acid excretion increased to a median of 82% (range, 46–126%), and the faecal fat excretion increased to a median of 22 g/day (range, 4–34 g/day), all clearly above normal. The faecal ¹⁴C-triolein/³H-oleic acid test showed triglycerides and free fatty acids to be equally malassimilated, which indicates malabsorption.

Key Words:

• Faecal fat excretion
• fat malabsorption
• fat maldigestion
• somatostatin