High serum gastrin levels in thyrotoxic patients.

High gastrin levels were found in twenty-one out of fifty-six consecutive patients (38%) with thyrotoxicosis. Following return to euthyroidism gastrin levels generally fell, but twelve patients (21%) remained hypergastrinaemic. Six of these patients (11%) had achlorhydria indicating atrophic gastritis of the antrum sparing type. No correlation between gastrin and triiodothyronine values was found. It is suggested that gastrin levels should be measured in thyrotoxic patients after treatment, and further control instituted in patients with raised gastrin levels. The relationship between gastric function, gastrin release and thyroid function seems complex. The interactions may involve both a direct effect of thyroid hormone on gastric acid production, adrenergic influences on gastrin release and linked phenomena with development of thyroid and gastric auto-immune diseases.