What is losartan?
Losartan (sold under the brand name Cozaar) is a medication used for the treatment of high blood pressure or hypertension, heart failure, and helps to prevent kidney damage due to diabetes. Generally, it is marketed as potassium salt of the aromatized negatively charged tetrazole or losartan potassium. It is a class of drugs called angiotensin II receptor antagonists.
It works better than ACE inhibitors like lisinopril, captopril, enalapril, and ramipril. The full effects of losartan may show after six weeks of dosing. Losartan dosage causes various common and serious side effects in your body.
The common side effects after losartan dosing are muscle cramps, stuffy nose, cough, high blood potassium level, and anemia or hemoglobin deficiency. Serious side effects after losartan dosing may include angioedema, low blood pressure, and kidney problems.
It works by blocking the action of certain natural substances which tighten the blood vessels and allow the flow of blood more smoothly from other organs to the heart. Losartan use during pregnancy may harm your developing fetus. It is also not recommended to use during breastfeeding.
It is an essential medicine approved by World Health Organization. Losartan is the most commonly prescribed generic medication used for United States patients.
Losartan potassium
It is a white crystalline powder soluble in water, alcohol, acetonitrile, or 2-butanone. It is marketed as the potassium salt of the aromatized negatively charged tetrazole.
Chemically, losartan potassium is 2-butyl-4-chloro-1-[p-(o-1H-tetrazol-5-ylphenyl)benzyl]imidazole-5-metahnol monopotassium salt. The empirical formula of such salt is C22H22CIKN6O with a molecular weight of 461.01.
Losartan uses
Losartan is used alone or together with other medicines for lowering high blood pressure or hypertension in adults and children. It is a suitable medicine used for the reduction of renal disease caused by diabetes. It is recommended for seniors (age above 55) who doses not tolerated ACE inhibitors.
Generally, high blood pressure increased the workload of our heart and arteries. If you suffer from high blood pressure for a long time, your heart and arteries may not function properly. Hence your blood vessels of the brain, heart, and kidneys are damaged. It results in various health problems such as stroke, heart failure, or kidney failure.
Losartan medication is not only used for the reduction of high blood pressure but also used for the treatment of ventricular hypertrophy (enlarged heart muscle), kidney dysfunction, and diabetic nephropathy.
How does losartan work?
It is a class of angiotensin II receptor blockers. It works by blocking the action of angiotensin II, a substance in your body that creates your blood vessels to tighten and narrow. Hence after losartan medication, your blood vessels widen and relax. As a result, the supply of blood and oxygen from other organs to the heart increases.
The mechanism of action of all angiotensin II receptor antagonists like losartan, valsartan, azilsartan, candesartan, eprosartan, irbesartan, olmesartan, and telmisartan is the same. But they are better to work than ACE inhibitors like lisinopril, captopril, enalapril, ramipril, etc.
How does losartan help in heart failure?
It is used alone or combined with other medications to treat heart problems. Losartan is in a class of medicine that block the action of certain natural substances that causes vasoconstriction and aldosterone release.
It also reduces plasma and extracellular fluid volume which decreases the cardiac output in your body. Hence losartan allows your blood to flow more smoothly or your heart to pump more efficiently. Therefore, it is used to decrease the risk of stroke or heart failure in people.
Losartan dosage
Losartan tablet (brand name: Cozaar) is available in the market with the strength of 25 mg, 50 mg, and, 100 mg. It is taken by mouth and used mainly for the treatment of high blood pressure or hypertension, heart failure, and diabetic nephropathy.
The tablet is usually taken once or twice a day with or without food. The starting and maximum dosing of losartan are given below the table,
| Medication |
Starting dose | Maximum dose | |
| High blood pressure | Adult | 50 mg/day | 100 mg/day |
| Pediatric | 0.7 mg/kg/day | 50 mg/day | |
| Diabetic nephropathy | 50 mg/day | 100 mg/day | |
Dose in high blood pressure
Adult dose
The starting adult dose for hypertension is 50 mg orally once per day with a maximum dose of 100 mg orally per day. Your doctor may increase the starting dose according to your blood pressure after medication.
Pediatric dose
The usual initial dose is 0.7 mg /kg for pediatric patients aged above 6 years. Your doctor may increase the dose up to 50 mg.
Dose for diabetic nephropathy
The starting adult dose for diabetic nephropathy is 50 mg orally once per day with a maximum dose of 100 mg orally once per day. Your doctor can maintain the dose according to your need.
Side effects of losartan
Losartan medication causes various types of common and serious side effects after taking. Therefore, always consult your doctor or pharmacist before taking this medication.
Common side effects
The most common side effects of losartan are,
- Dizziness, faintness
- Leg, knee, or back pain
- Muscle cramps or weakness
- Blurred vision
- Nausea or vomiting
- Diarrhea
- Decreased sensitivity to touch
Serious side effects
If you feel any serious side effects always call your doctor and tell them about the problems. The serious side effects are,
- Swelling of your face, tongue, throat, lips, eyes, hands, and lower legs
- Hoarseness
- Angioedema
- Low blood pressure
- Fast or irregular heartbeat
- Difficulty in breathing
- Pain in your chest
- Kidney problems
These are not a complete list of side effects after losartan medication. Your doctor may guide you about its full adverse effects.
Losartan warning
- It can cause allergic symptoms like trouble breathing, swelling of your throat or tongue, and hives. Tell your doctor if you feel any allergic symptoms after taking losartan tablets.
- Drinking alcohol during medication increases the risk of too-low blood pressure.
- Always tell your doctor if you have kidney problems.
- Always tell your doctor if you have liver problems. If you have liver problems, your body does not break down losartan like normal people. Therefore, doctors may lower your starting dosage.
- Do not take it during your pregnancy period. It may cause death or serious effects on your developing fetus. Therefore, this medication should immediately stop when pregnancy is detected
- It is not recommended for breastfeeding women. If your baby was born prematurely, always tell your doctor before taking it.
- You should not use potassium supplements or salt-containing potassium during losartan medication because it can cause hyperkalemia in people.
