Drug Interactions of antidiabetics (Part 2):

Drug Interactions of Exenatide and Pramlintide:

¢ More frequent monitoring of INR is recommended when initiating or changing the dose of exenatide during Warfarin therapy due to increased risk of bleeding.

¢ To avoid Digoxin toxicity, the plasma levels and clinical efficacy of digoxin should be monitored when Exenatide is used concurrently.

¢ Antibacterials should be taken at least one hour before Exenatide, to prevent delayed absorption and reduced efficacy of antibacterials.

¢ Increased dose of Exenatide or Pramlintide may be required due to its interaction with Thyroid hormones which decrease its effectiveness.

¢  Danazol is associated with insulin resistance and it interacts with Exenatide or Pramlintide to increase blood sugar level.

¢ The risk of hypoglycemia is increased by the concomitant use of Exenatide or Pramlintide and Trandolapril.

¢ The diabetics should bring a list of all of the drugs they are taking, including prescription drugs, over-the-counter drugs, and any supplements, herbal products, etc. during their visit to the doctor or pharmacist, to minimize the possibility of potentially dangerous combinations.

Drug Interactions of Antidiabetics (Part 1):

Interactions of Insulin:

¢ The therapeutic efficacy of Insulin either increased or decreased by interacting with other drugs.

¢ Further reductions of blood glucose or exacerbation of hypoglycemia may be resulted due to the concomitant use of Insulin and drugs such as Fluoroquinolones, Anabolic steroids (nandrolone, methandienone, testosterone propionate or stanozolol), Antimalarials (Hydroxychloroquine, chloroquine), Orlistat, Bitter melon, Ginkgo, Ginseng, Gymnema extracts, Fenugreek and Alcohol.

¢ The blood sugar level may be elevated by the coadministration of Insulin and Antipsychotics.

¢ The therapeutic efficacy of Insulin is reduced in smokers due to decreased absorption.

¢ Betablockers may delay the recovery from hypoglycemia induced by Insulin.

¢ Thiazolidinediones (Pioglitazone or rosiglitazone) may potentiate the renal effects of insulin on sodium and water retention which may increase the incidence of heart failure.

¢ The diabetics are encouraged to ask their doctor or pharmacist to look over their medication list for any potentially dangerous combinations.

Drug Interactions between Antidiabetics, Antihypertensives and Lipid regulating drugs:

More presentations from Naina Mohamed Pakkir Maideen

Ø Diabetes patients may need other drugs to control the coexisting problems-

·       ACEIs or ARBs for high blood pressure, heart, or kidney failure

·       Diuretics, CCBs or beta-blockers for high blood pressure

·       Statins for high cholesterol

·       Fibrates for high triglycerides

·       Aspirin or Clopidogrel to prevent a heart attack

Ø Combined use of Antidiabetics, Antihypertensives and Lipid regulating drugs may result into either decreased effectiveness or increased adverse effects of drugs.

Ø Thiazide diuretics tend to have diabetogenic effect and hence they reduce the effectiveness of Antidiabetics such as Sulfonylureas, Meglitinides, Thiazolidinediones and DPP4 inhibitors.

Ø The risk of hypoglycemia is increased by the concomitant use of Antidiabetics (sulfonylureas, meglitinides and Metformin) and ACE Inhbitors.

Ø Concurrent therapy with a Beta blocker and an antidiabetic may increase the risk of hypoglycemia or hyperglycemia due to altered glucose metabolism.

Ø Thiazide diuretics, Potassium sparing diuretics (Amiloride or Triamterene) or Nifedipine may increase the risk of lactic acidosis when they are coadministered with Metformin.

Ø The antihypertensive efficacy of Nifedipine and Nimodipine may be decreased by the addition of Pioglitazone.

Ø Concomitant use of repaglinide and gemfibrozil is Contraindicated due to the inhibition of CYP2C8 enzyme mediated metabolism of repaglinide by Gemfibrozil which leads to hypoglycemic risk.

Ø The risk of hypoglycemia is elevated by the coadministration of Antidiabetics (Pioglitazone, Rosiglitazone and Sulfonylureas) and Gemfibrozil.

Ø Calcium channel blockers (Verapamil or Nifedipine) inhibit CYP3A4 mediated metabolism of Statins and increase risk of musculoskeletal toxicity (Myopathy, Rhabdomyolysis).

Ø To avoid serious drug interactions, the diabetics should consult their physician or pharmacist particularly when they begin to take a new medicine.