GENSULIN preparations should not be mixed with animal insulin and biosynthetic insulin produced by other manufacturers. Many frequently used drugs (for example some antihypertensive drugs, cardiac drugs, drugs lowering the level of lipids in serum, thyroid replacement drugs, epilepsy treatment drugs, salicylates, antibacterial drugs, orally taken contraceptives) may affect the insulin action and the efficiency of insulin therapy.
Therefore patients should always inform their physician about constantly or temporally taken drugs. They should ask for advice a doctor or a pharmacist about over-the-counter available drugs. A drug that has never been taken before should always be consulted with a physician. A physician's patients are consulting for other than diabetes reason should always be informed about the insulin therapy.
Drugs and substances strengthening insulin action: Beta-blockers, chloroquine, ACE inhibitors, MAO inhibitors (antidepressants), methyldopa, clonidine, pentamidine, salicylates, anabolic steroids, cyclophosphamide, sulphonamide antibiotics, tetracyclines, antibacterial quinolones and ethyl alcohol.
Drugs reducing insulin action: Diltiazem, dobutamine, estrogens (also orally taken contraceptive pills), phenothiazine, phenytoine, thyroid hormones, heparin, calcitonin, corticosteroids, antiviral drugs applied in HIV infections, niacin, and diuretic thiazides.