Reuters Health Information (2007-11-14): Octreotide may enhance control of portal hypertension
Clinical
Octreotide may enhance control of portal hypertension
Last Updated: 2007-11-14 15:41:31 -0400 (Reuters Health)
NEW YORK (Reuters Health) - In patients with cirrhosis, the reduction in portal pressure induced by propranolol is apparently enhanced by the addition of octreotide, a long-acting synthetic somatostatin analogue. The finding is reported by researchers from Argentina in the October issue of the American Journal of Gastroenterology.
Earlier in vitro research had indicated that octreotide exerts a vasoconstrictive action on the vascular smooth muscle of isolated mesenteric arteries of rats. Since chronic pharmacological treatment of portal hypertension is largely based on non-selective beta-blockers, and since one of the effects of such drugs is splanchnic arteriolar vasoconstriction, the researchers theorized that octreotide with a beta-blocker might achieve a larger portal hypotensive effect than a beta-blocker alone.
Dr. Julio Vorobioff at Sanatorio Parque in Rosario and colleagues conducted two successive trials involving the same 28 patients.
In the first study, patients were randomly assigned to octreotide 200 mcg or to placebo. The patients receiving octreotide had a mean reduction in hepatic vein pressure gradient (HVPG) versus baseline of 8.6% at 60 minutes after administration (p < 0.05). After completion of this study, all patients were started on oral propranolol, initially 20 mg b.i.d.
In the second study, the same patients continued on propranolol with either octreotide or placebo. After titration, the median propranolol dose was 106 mg/day.
The HVPG in patients receiving octreotide in addition to propranolol decreased an average of 9.9% after 60 minutes, versus the updated baseline (p < 0.05). HVPG reduction was significantly higher in this group compared with the propranolol-plus-placebo group.
The researchers caution, however, that given octreotide's pharmacokinetics, "results observed at 60 minutes may represent its peak effect."
They also note octreotide's variable results, in that some patients who responded to it well in the first study did not in the second, and for some other patients, that situation was reversed.
Am J Gastroenterol 2007;102:2206-2213.
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