Uses and Side Effects of Losartan
The Bottom Line
Losartan (Cozaar) is a common medication used to lower blood pressure. It is typically well-tolerated and doesn’t interact with many drugs, foods, or supplements. Losartan may cause side effects, including fatigue, dizziness, and fainting. It is not safe to use during pregnancy, and can have dangerous effects if excessive amounts are consumed.
What is Losartan used for?
Losartan is a prescription drug primarily used to treat high blood pressure (hypertension). It is also prescribed as a treatment for conditions that affect the heart, kidneys, and blood vessels, such as heart failure and chronic kidney disease. Losartan works by relaxing the blood vessels throughout the body. This, in turn, reduces the workload of the heart and kidneys. Losartan is approved by the US Food and Drug Administration (FDA) to treat hypertension in adults and children and kidney disease in diabetics. Losartan is also used to reduce the risk of stroke in people with certain health conditions.
Lisinopril vs. losartan vs. valsartan: What are the differences?
Lisinopril, losartan, and valsartan are all medications used to treat high blood pressure. All three of these medications work to lower blood pressure by relaxing blood vessels. In addition to lowering blood pressure, these medications can also be used to treat different health conditions. Lisinopril and valsartan are approved to help reduce the risk of death after a heart attack, while losartan helps protect kidney function in diabetic individuals.
Lisinopril can increase the cough reflex, leading to a dry, hacking cough. The cough is typically not dangerous, but it can be bothersome enough that the person taking the medication will need to switch to a different blood pressure medication. Losartan and valsartan are much less likely to cause coughing.
Finally, there are different reasons why a doctor may choose to prescribe one of these medications over the other. There is some evidence suggesting that losartan works for a longer period of time in the body, while valsartan has stronger blood pressure lowering effects and lisinopril may be more effective in reducing long term risk of heart complications.
What are the long-term side effects of losartan?
Common side effects of losartan include dizziness, fainting, lightheadedness (especially when standing or sitting up quickly), and tiredness. A rare, but serious, side effect is swelling of the tongue, lips and eyes. This is called “angioedema” and it is potentially life-threatening. People who take losartan should seek medical attention immediately if this type of swelling occurs. Losartan should not cause hair loss and has minimal to no effect on weight management. When taken appropriately, losartan typically does not cause dangerously low blood pressures to occur. If you experience signs or symptoms of low blood pressure (including lightheadedness or fainting) while taking losartan, contact your doctor to discuss whether a change in the dosing of medication is needed.
Over time, losartan may cause the kidneys to keep too much potassium in the body or may reduce kidney function. Signs of these long-term side effects can include heart palpitations, shortness of breath, or changes in the quantity or appearance of urine. While taking losartan, your doctor should regularly monitor your electrolytes and kidney function.
Losartan interactions and contraindications: Can you drink alcohol while taking Losartan?
Losartan does not typically cause serious interactions with other medications. Grapefruit juice consumption may have a small effect on Losartan, but this is unlikely to cause any serious changes in blood pressure. Since both alcohol and caffeine can affect blood pressure, use caution when consuming these substances along with losartan.
Losartan warnings: why was losartan recalled?
In recent years, specific batches of losartan were recalled due to the detection of impurities in the losartan tablets. These impurities belong to a family of chemicals called nitrosamines. Nitrosamines are found in common household and food items, like hot dogs. The nitrosamines found in losartan included nitrosodiethylamine (NDEA) and N-methylnitrosobutyric acid (NMBA). These nitrosamines are associated with cancer development. The tablets made in the recalled losartan batches were found to contain unacceptable levels of nitrosamines, and because of this the manufacturer announced a voluntary recall to maintain safety standards. There were no reports of adverse effects linked to this recall.
Is Losartan safe during pregnancy?
Because losartan use may cause harm during fetal development, losartan is not recommended during pregnancy. If you are pregnant and have high blood pressure, talk with your doctor to determine the safest medication regimen for you and your unborn baby.
What should you do if you accidentally took a double dose of Losartan?
Taking an extra dose of losartan can lead to an abnormally low blood pressure. If someone develops unexplained or unexpected symptoms after taking losartan, or if too much was taken, get guidance from Poison Control immediately. Help from Poison Control is available online at www.poison.org and by phone at 1-800-222-1222. Both options are free, confidential, and available 24 hours a day.
Written by:
Elise Drummond, PharmD. Candidate, 2023
Pharmacy Student
Medically reviewed by:
Kelly Johnson-Arbor, MD
Medical Toxicologist
Poisoned?
Call 1-800-222-1222 or
Prevention Tips
- Use child-resistant containers for all medications, prescription and nonprescription. Keep in mind that these closures are child-resistant, not child proof.
- Keep medications in locations that are out of sight and hard to reach for children.
- Talk with your doctor if you experience side effects while taking medications.
- Keep a current list of all medications, supplements, and vitamins that you are taking.
This Really Happened
A 3-year-old boy found his mother’s bottle of losartan 25 mg tablets that had been left on the counter. He chewed and swallowed 8 pills. He vomited once, developed a rash on his arms, and became dizzy. He was taken to a hospital where he was admitted for observation. He experienced low blood pressure readings over the next several hours, but by the next morning he had recovered completely and was able to be discharged home.For More Information
References
Poisoned?
Call 1-800-222-1222 or
Prevention Tips
- Use child-resistant containers for all medications, prescription and nonprescription. Keep in mind that these closures are child-resistant, not child proof.
- Keep medications in locations that are out of sight and hard to reach for children.
- Talk with your doctor if you experience side effects while taking medications.
- Keep a current list of all medications, supplements, and vitamins that you are taking.