Virtually all symptoms in patients with
Zollinger-Ellison syndrome are due to
acid hypersecretion, thus the control of
acid secretion is the first and most important step in the management of patients with this syndrome. Antisecretory medication is prescribed as soon as the diagnosis of
Zollinger-Ellison syndrome is made, as patients may bleed or perforate with little warning.
Acid output is reduced to less than 10 mmol/h to heal mucosal lesions, but in patients with a
Billroth I or II
gastrectomy and those with severe oesophagitis and
stricture formation,
acid output is reduced to less than 5 or less than 1 mmol/h.
Acid output and not symptomatic response is a reliable guide of the adequacy of
therapy. In sufficient doses, all H2-receptor antagonists are useful; however, side effects associated with
cimetidine therapy limit its use. The ratio of potencies of
cimetidine:
ranitidine:
famotidine is 1:4:32.
Ranitidine given as a 50-mg intravenous bolus, followed by a continuous infusion of 0.5 mg.kg/h, controls
acid hypersecretion acutely in patients with
Zollinger-Ellison syndrome.
Acid output is checked after 4 h, and the dose increased until
acid output is less than 10 mmol/h. In 70% of patients with
Zollinger-Ellison syndrome, 1 mg.kg/h reduces
acid output to less than 10 mmol/h; however, doses up to 4 mg.kg/h have been used. When patients are switched to oral
ranitidine, a useful dosage conversion is to administer 1.5 times the total daily intravenous dose in four equal doses every 6 h. Four doses of oral
drug are given before the infusion is stopped. Six hours after the first/last oral dose,
acid output is checked. In our patients, the mean dose of
ranitidine was 2100 mg/day (range, 450-9200 mg/day). No serious toxicity was observed.
Omeprazole, which has a long duration of action and is a potent inhibitor of gastric acid secretion, has simplified management. Once-daily dosing is sufficient in most patients, and a reasonable starting dose is 60 mg daily. The dose may be increased to 120 mg once daily; if this dosage fails to control
acid secretion, 60 mg is administered every 12 h. In our studies, the median dose was 90 mg/day (range, 20-120 mg/day).
Omeprazole was more effective than H2-receptor antagonists in providing symptom relief and mucosal healing and did not cause significant toxicity. In particular, no gastric
carcinoid tumours developed during four years of use.
Omeprazole is, therefore, the treatment of choice for control of
acid secretion in patients with
Zollinger-Ellison syndrome.(ABSTRACT TRUNCATED AT 400 WORDS)