Drug Interactions of Antihypertensives (Part 2):

Drug Interactions of Angiotensin Receptor Blockers:

More presentations from Naina Mohamed Pakkir Maideen

©    Angiotensin Receptor Blockers (ARBs) are useful in the treatment of Hypertension, Congestive Heart Failure and Diabetic Nephropathy.

©    ARBs block the action of Angiotensin II by preventing the binding of angiotensin II angiotensin receptors on the muscles surrounding blood vessels. Inhibited binding of Angiotensin II, results in to vasodilation causing reduction of blood pressure. The function of a failing heart could be improved by lowered blood pressure making it easier for the heart to pump blood.

©    ARBs can interact significantly with many drugs including Aliskiren, ACE Inhibitors, Lithium, CYP2C9 Inhibitors, CYP3A4 Inhibitors, CYP3A4 Inducers, Potassium sparing diuretics, Trimethoprim, NSAIDs and Insulin.

©    It is contraindicated to use ARBs along with Aliskiren concomitantly in diabetes patients, due to increased risk of Hyperkalemia, Renal impairment and Hypotension.

©    Coadministration of ARBs and ACE Inhibitors (Captopril, Lisinopril, Perindopril, etc.) may result in to increased risk of adverse events (Hypotension, syncope, hyperkalemia, changes in renal function, acute renal failure).

©    Concomitant use of ARBs and Lithium may result in to Lithium toxicity (weakness, tremor, excessive thirst, confusion).

©    The risk of toxicity of ARBs may be elevated by the concomitant use of ARBs and CYP2C9 Inhbitors (Entacapone, Ceritinib, etc.) or CYP3A4 Inhibitors (Darunavir, Clarithromycin, Cobicistat, Nilotinib, Crizotinib, Ceritinib, Piperaquine, etc.).

©    Loss of therapeutic efficacy of ARBs may occur in patients taking CYP3A4 Inducers (Carbamazepine, Dabrafenib, etc.).

©    Severe arrhythmias may occur in patients taking ARBs and Potassium Sparing Diuretics (Spiranolactone, Amiloride, Triamterene, etc.) or Trimethoprim, due to increased risk of Hyperkalemia.

©    Use of NSAIDs in patients taking ARBs may result in to renal dysfunction or decreased antihypertensive efficacy.

©    Increased risk of Hypoglycemia noted in patients taking ARBs along with Insulin.

©    Concomitant use of Telmisartan and Digoxin may result in to digoxin toxicity (Slow pulse, Irregular heartbeats, Nausea, Loss of appetite, Visual changes, etc.).

©    Use of ARBs during pregnancy is strongly discouraged.

©    It is recommended to discontinue either ARBs or breast feeding.