Olmesartan, available as the brand Benicar, is a prescription drug for treating high blood pressure and congestive heart failure. Benicar also is effective for treating diabetic nephropathy, or kidney disease, in people with diabetes and high blood pressure. Combining the medicine with potassium supplements or drugs that elevate potassium levels is typically inadvisable, according to Drugs.com.
Benicar is classified as an angiotensin II receptor antagonist, also called an angiotensin II receptor blocker. It widens blood vessels by blocking the action of angiotensin II, a hormone that causes constriction of blood vessels. Widening blood vessels helps the heart to pump more efficiently and blood to flow more easily. Inhibiting angiotensin II causes reduced secretion of another hormone, aldosterone. Aldosterone regulates the removal of potassium by the kidneys.
Substances to Avoid
If you take Benicar, consult your doctor before consuming salt substitutes containing potassium or any vitamin and mineral supplements that contain potassium. Combining Benicar or any other angiotensin II receptor antagonist with these substances increases the risk of high potassium levels, or hyperkalemia. This risk also increases if you combine Benicar with potassium-sparing diuretics. These diuretics stop the kidneys from removing potassium; they were developed because other diuretics can lead to excessive loss of potassium. Potassium-sparing diuretics include spironolactone, known as the brand Aldactone, and triamterene, known as the brand Dyrenium.
If you take Benicar and experience signs of hyperkalemia, seek immediate medical attention because the condition can become life threatening. Symptoms may include nausea, vomiting, weakness, listlessness and confusion. More serious effects may include loss of consciousness, changes in nerve and muscle control, muscle paralysis, a weak pulse, a slow or irregular heartbeat and cardiac arrest.
Some people are at higher risk for hyperkalemia than others when taking Benicar, explains Drugs.com. Angiotensin II receptor antagonists have been associated with hyperkalemia in patients with kidney dysfunction. Diabetes and severe or worsening heart failure are other risk factors. Elderly people also are more likely to develop hyperkalemia when taking Benicar.