Effects of cimetidine on in vitro transformation of peripheral monocytes to macrophages in healthy volunteers and cancer patients

Potential immunological consequences of pharmacological suppression of gastric acid production in patients with multiple sclerosis

Corticosteroids are standard treatment for patients with multiple sclerosis experiencing acute relapse. Because dyspeptic pain is a common side effect of this intervention, patients can be given a histamine receptor-2 antagonist, proton pump inhibitor or antacid to prevent or ameliorate this disturbance. Additionally, patients with multiple sclerosis may be taking these medications independent of corticosteroid treatment. Interventions for gastric disturbances can influence the activation state of the immune system, a principal mediator of pathology in multiple sclerosis. Although histamine release promotes inflammation, activation of the histamine receptor-2 can suppress a proinflammatory immune response, and blocking histamine receptor-2 with an antagonist could shift the balance more towards immune stimulation. Studies utilizing an animal model of multiple sclerosis indicate that histamine receptor-2 antagonists potentially augment disease activity in patients with multiple sclerosis. In contrast, proton pump inhibitors appear to favor immune suppression, but have not been studied in models of multiple sclerosis. Antacids, histamine receptor-2 antagonists and proton pump inhibitors also could alter the intestinal microflora, which may indirectly lead to immune stimulation. Additionally, elevated gastric pH can promote the vitamin B12 deficiency that patients with multiple sclerosis are at risk of developing. Here, we review possible roles of gastric acid inhibitors on immunopathogenic mechanisms associated with multiple sclerosis.

Case report: successful treatment with cimetidine and zinc sulphate in chronic mucocutaneous candidiasis

The authors evaluated the clinical efficacy of a treatment with cimetidine and zinc sulphate in a patient with chronic mucocutaneous candidiasis. Cimetidine was given at a dose of 400 mg three times daily; zinc sulphate at a dose of 200 mg daily, then adjusted to maintain blood zinc levels at the upper normal range. This treatment lasted 16 months. An impressive and significant reduction of the infectious events and an increased CD4 (helper/inducer) cell counts were observed. The authors conclude that this combined immunopotentiating treatment is safe and inexpensive to treat immunodeficiency disorders.