The Endocrine and Metabolic Effects of Cimetidine

Abstract

SUMMARY Serial blood sampling in nine patients treated with cimetidine (1 g/day) showed that PRL values were within the normal range apart from a stress‐induced initial rise. Hormonal and metabolic profiles from 08.30 to 18.30 h were performed in six patients before and after 1 month's treatment with cimetidine (1 g/day). Circulating PRL, LH, FSH, GH, TSH T3, T4 and testosterone were similar before and after treatment. The mean blood glucose fell from 5·4 ± 0·3 mmol/l to 4·8 ± 0·2 mmol/l on cimetidine (P<0·02). Small changes were also observed in blood pyruvate, lactate, 3‐hydroxybutyrate and the (lactate)/(pyruvate) ratio. The effects of oral or i.v. cimetidine on the circulating concentrations of insulin, glucose and intermediary metabolites were investigated in normal subjects. Intravenous cimetidine (100 mg/h for 4 h) given to fasting subjects decreased blood glucose and serum insulin by 15 and 34% respectively at 150 min. During an oral GTT, i.v. cimetidine caused a striking decline in blood glucose, lactate and pyruvate responses compared with control studies, although the serum insulin was similar to control values. When given for 48 h before the study, oral cimetidine did not alter basal serum insulin and blood glucose, lactate, pyruvate, alanine, glycerol and 3‐hydroxybutyrate levels. However, 150 min after an oral GTT the serum insulin was increased by 47% by oral cimetidine although the blood glucose was not significantly changed compared with the control day. Oral cimetidine had no effect on the blood glucose or serum insulin during an i.v. GTT. These results show that oral cimetidine given at therapeutic doses to patients with peptic ulcers does not produce consistent changes in circulating anterior pituitary hormones. Oral cimetidine given to patients for 1 month and i.v. cimetidine given to normal subjects have mild hypoglycaemic effects. Oral cimetidine administered over 48 h to normal subjects has little effect on blood glucose concentration.

Famotidine inhibits glycogen synthase kinase-3β: An investigation by docking simulation and experimental validation

“…Generally, famotidine is well tolerated in patients with various disorders like cardiovascular, renal and hepatic dysfunctions, moreover it is considered to have excellent safety profiles 3 . Nevertheless, it is well known that H 2 -receptor inhibitors affect hormone metabolism 4 ; however, their effect on glucose metabolism is not well investigated. In fact several discrepancies are reported concerning the effects produced by these compounds on glycemic level [4][5][6][7] .…”

“…Nevertheless, it is well known that H 2 -receptor inhibitors affect hormone metabolism 4 ; however, their effect on glucose metabolism is not well investigated. In fact several discrepancies are reported concerning the effects produced by these compounds on glycemic level [4][5][6][7] . In addition, most studies have investigated the effect of cimetidine and ranitidine and only few data are available for famotidine.…”