About losartan

Written by shelley moore
  • Share
  • Tweet
  • Share
  • Email

Losartan potassium is a medication prescribed to reduce high blood pressure and to treat diabetic nephropathy, a kidney disorder experienced by some people with diabetes. It also is used to decrease the risk of a stroke in people with high blood pressure and left ventricular hypertrophy (LVH). LVH involves an enlargement of the left pumping chamber of the heart, and can cause irregularities in the way the heart pumps blood.


Losartan is available as the brand Cozaar, manufactured by Merck & Co. It is classified as an angiotensin II receptor blocker, a drug which blocks the action of an enzyme that causes blood vessels to narrow. This allows blood vessels to relax and results in lower blood pressure. Lowering blood pressure decreases the risk of heart attack or stroke.


Losartan is available in tablets of 25 mg, 50 mg and 100 mg. For high blood pressure, physicians typically start patients with 50 mg once a day, then increase or decrease the dosage depending on the response. It may be several weeks before losartan takes full effect.

Minor Side Effects

Many side effects are associated with losartan, but all are uncommon. The most frequent side effects reported usually are temporary and include constipation or diarrhoea, dizziness, insomnia, muscle cramps, runny nose and nasal congestion.

Serious Side Effects

More serious side effects can occur with losartan use, but they are rare. These include anxiety or depression, anaemia, bladder infections, blurred vision, fibromyalgia, gout and migraine headaches. Very rarely, a disorder called rhabdomyolysis can occur. This condition causes the breakdown of skeletal muscle, releasing a protein into the bloodstream that can damage the kidneys. Pregnant women should not take losartan because the drug can cause serious birth defects and may even be fatal to the unborn baby.

Drug Interactions

Losartan may increase blood potassium levels, which can lead to heart arrhythmia. People taking other substances that increase potassium blood levels may need to avoid using losartan. These drugs include potassium-sparing diuretics such as amiloride, potassium supplements and salt substitutes containing potassium. Additionally, non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and aspirin can reduce the ability of losartan to lower high blood pressure.

Don't Miss

  • All types
  • Articles
  • Slideshows
  • Videos
  • Most relevant
  • Most popular
  • Most recent

No articles available

No slideshows available

No videos available

By using the eHow.co.uk site, you consent to the use of cookies. For more information, please see our Cookie policy.