A number of substances affect glucose metabolism and may require dose adjustment of Insulin Glargine.
Substances that may enhance the blood-glucose-lowering effect and increase susceptibility to hypoglycemia include oral antidiabetic agents, ACE inhibitors, disopyramide, fibrates, fluoxetine, MAO inhibitors, pentoxifylline, propoxyphene, salicylates and sulfonamide antibiotics.
Substances that may reduce the blood-glucose-lowering effect include corticosteroids, danazol, diazoxide, diuretics, glucagon, isoniazid, estrogens and progestogens, phenothiazine derivatives, somatropin, sympathomimetic agents (e.g., epinephrine (adrenaline), salbutamol, terbutaline), and thyroid hormones. Beta-blockers, clonidine, lithium salts or alcohol may either potentiate or weaken the blood-glucose-lowering effect of Insulin. Pentamidine may cause hypoglycemia, which may sometimes be followed by hyperglycemia.
In addition, under the influence of sympatholytic medicinal products such as beta-blockers, clonidine, guanethidine and reserpine, the signs of adrenergic counter regulation may be reduced or absent.