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Medically Approved

Losartan side effects

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More common side effectsMild side effectsSerious side effectsFAQSide effects in detailCouponWarningsAsk your doctor
Losartan oral tablet is used to treat high blood pressure and diabetic kidney disease and lower the risk of stroke. It’s an angiotensin II receptor blocker (ARB) that may cause mild or serious side effects, including dizziness and harm in pregnancy.
Medically reviewed by Brittany A. Duke, PharmD, RPh
Updated on

Specifically, the Food and Drug Administration (FDA) has approved losartan oral tablet to:

This article describes possible side effects of losartan oral tablet. You’ll also find information on cost savings and coupon options for losartan.

Losartan oral tablet is a generic version of the brand-name drug Cozaar. To learn more about Cozaar, talk with your doctor.

You can explore this overview article to learn more about losartan oral tablet, including the drug’s uses, dosage, ways to save on cost, and more.

* A person’s race may affect how their body responds to losartan oral tablets for this condition. To learn more, talk with your doctor.

Boxed warning: Risk of harm if taken during pregnancy

Losartan has a boxed warning for the risk of harm if taken during pregnancy. Boxed warnings are serious warnings from the Food and Drug Administration (FDA).

For details, see “Losartan and pregnancy” in the “Warnings for losartan” section below.

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More common side effects of losartan

Losartan oral tablet may cause mild or serious side effects. Below are some of the more common side effects of this medication.

Commonly reported side effects of losartan oral tablet include:

  • dizziness
  • upper respiratory infection, such as the common cold
  • stuffy nose
  • back pain

Mild side effects of losartan

Losartan may cause certain mild side effects. Most often, mild side effects are temporary and can be easily managed. Tell your doctor or pharmacist if you have side effects that don’t go away or become bothersome.

Mild side effects of losartan oral tablet that occurred in studies include:

* To learn more about this side effect, see the “Side effects of losartan in detail” section below.

Losartan oral tablet may cause more mild side effects than those listed above. For details, see the drug’s prescribing information.

Serious side effects of losartan

Losartan may cause certain serious side effects. If you have any serious side effects from losartan oral tablet, call your doctor right away. But if you think you’re having a medical emergency or your side effects feel life threatening, take immediate action. Call 911 or a local emergency number, or go to the nearest emergency room.

After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. Visit MedWatch’s website if you’d like to notify the FDA about a side effect you’ve had with losartan oral tablet.

Serious side effects of losartan oral tablet that occurred in studies include:

* To learn more about this side effect, see the “Side effects of losartan in detail” section below.
Losartan oral tablet has a boxed warning for this side effect. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). To learn more, see “Losartan and pregnancy” in the “Warnings for losartan” section below.

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Common questions about side effects of losartan

Here are answers to some common questions about side effects of losartan oral tablet. If you have other questions, talk with your doctor or pharmacist.

Does losartan cause long-term side effects?

It’s possible for losartan to cause long-term side effects in rare cases. Long-term side effects are those that start either:

  • during treatment and continue for a long time, possibly after you’ve stopped taking the drug, or
  • after you’ve taken the drug for a long time or have ended treatment

Long-term side effects reported in people taking losartan include:

Talk with your doctor or pharmacist if you have more questions about losartan’s long-term side effects.

* To learn more about this side effect, see the “Side effects of losartan in detail” section below.
Losartan oral tablet has a boxed warning for this side effect. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). To learn more, see “Losartan and pregnancy” in the “Warnings for losartan” section below.

Does losartan 50 mg cause different side effects than the drug’s other strengths?

No, different strengths of losartan don’t cause different side effects. Side effects are the same for any strength of the drug.

That said, as with any drug, your risk of side effects generally increases if you take a higher dose. Your doctor or pharmacist can answer questions about how your losartan dose affects your risk of side effects. But different strengths and doses aren’t expected to cause different side effects.

Will I experience certain side effects when missing doses or stopping losartan?

No, that’s not expected. Withdrawal symptoms haven’t been reported with missing doses or stopping losartan.

Withdrawal symptoms refer to side effects that can happen if you stop taking a drug your body needs to function like usual. This is known as dependence, and it’s different from drug misuse or addiction.

That said, if you miss doses of losartan, symptoms of your condition may return. Missing doses of losartan can also make the drug less effective for treating your condition. If you’d like some tips on remembering to take your medications, see this article.

If you stop taking losartan altogether, the condition it was treating will likely come back or worsen. For example, if you’re taking losartan to treat high blood pressure, your blood pressure will likely increase if you stop taking the drug.

It’s recommended that you do not stop taking losartan unless your doctor has told you to do so. If you’d like to stop taking losartan, your doctor can review other treatment options with you instead.

Does losartan cause weight gain or joint pain?

Losartan may cause joint pain, according to the drug’s studies.

On the other hand, weight gain wasn’t a side effect reported in the studies. But losartan can cause worsening kidney function in people with a kidney problem, such as chronic kidney disease. Unexplained weight gain can be a symptom of worsening kidney function. Other symptoms include swelling in your ankles, feet, or hands.

You should tell your doctor right away if you have a kidney problem and notice these symptoms while taking losartan. Your doctor can recommend ways to manage your condition.

Is dry cough a side effect of losartan?

Maybe. Though rare, dry cough has been reported with losartan since the drug was approved for use. Keep in mind that these reports happened after the drug’s initial studies. It’s not known for sure whether losartan or another factor caused the dry cough.

Losartan belongs to a group of drugs called angiotensin II receptor blockers (ARBs). Another group of drugs called angiotensin II converting enzyme (ACE) inhibitors are similar to ARBs. ACE inhibitors, such as lisinopril, are more likely to cause dry cough compared with ARBs.

It’s common for doctors to switch treatment for people with a dry cough from an ACE inhibitor to an ARB. This way, the dry cough may go away. This side effect is still possible with ARBs, but it’s relatively rare.

Talk with your doctor if you develop a dry cough while taking losartan. They can discuss ways to address your symptoms.

Can losartan cause eye-related side effects?

No, that’s not expected with losartan. Eye-related side effects weren’t reported in the drug’s studies.

Other medications prescribed for blood pressure and heart problems may cause dry eye. This includes beta-blockers and certain diuretics (water pills). Metoprolol (Lopressor, Toprol XL) is an example of a beta-blocker, and hydrochlorothiazide (Microzide) is an example of a thiazide diuretic.

Talk with your doctor or pharmacist if you’re concerned about eye-related side effects.

Note: Losartan can cause low blood pressure when sitting or standing up, which can cause temporary blurry vision for a few seconds or minutes. View the “Side effects of losartan in detail” below to learn more.

Side effects of losartan in detail

Below you’ll find details on some of the side effects of losartan oral tablet.

Low blood pressure when sitting or standing up

You may experience low blood pressure when sitting or standing up while taking losartan. This side effect is called orthostatic hypotension. It wasn’t common in the drug’s studies.

Symptoms can include:

  • feeling dizzy or lightheaded when standing or sitting up, which may lead to falls or fainting
  • nausea
  • weakness
  • blurry vision

Ways to manage

If you feel dizzy or lightheaded when standing or sitting up while taking losartan, lie down right away. Then, call your doctor. They’ll likely have you come for an appointment. This way, your doctor can examine you and advise whether it’s safe for you to keep taking losartan.

High blood potassium level

Treatment with losartan can cause high blood potassium as a side effect. This was rare in the drug’s studies.

Symptoms of high blood potassium include:

In some cases, especially when this condition is mild, high blood potassium may not cause symptoms.

Ways to manage

Your doctor will likely suggest you avoid using salt substitutes containing potassium if you’re taking losartan. They’ll also likely suggest you avoid taking any potassium supplements.

Your doctor will monitor your potassium level during treatment with losartan using a blood test. They can provide more information on how often they’ll order this test.

Call your doctor if you’re having symptoms of high blood potassium while taking losartan. Your doctor will likely have you come for an appointment. This way, they can examine you and recommend whether you should keep taking losartan. Your doctor may have you temporarily or permanently stop taking the drug. They may also prescribe treatment to help lower your potassium level.

Allergic reaction

For some people, losartan oral tablet can cause an allergic reaction. It’s not clear whether this side effect happened in studies. But it has been reported since losartan was approved for use.

Symptoms can be mild or serious, and they may include:

  • itchiness
  • skin rash
  • swelling under the skin, usually affecting eyelids, lips, hands, or feet
  • swelling of the mouth, tongue, or throat, which can make it hard to breathe
  • flushing (temporary warmth, redness, or deepening of skin color)

Ways to manage

For mild allergic reaction symptoms, such as a mild rash, call your doctor right away. They may recommend treatments to help manage your symptoms. They’ll also let you know whether you should keep taking the medication.

For severe allergic reaction symptoms, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms require immediate medical care because they can become life threatening. If you’ve had a serious allergic reaction to losartan oral tablet, your doctor may recommend taking a different medication instead.

Coupon for losartan

Visit this page to access Optum Perks coupons and get price estimates for losartan when you use the coupons. These coupons can provide significant savings on your prescription costs. 

Note: Optum Perks coupons cannot be used with insurance copays or benefits.

Warnings for losartan

Below are some factors you may want to discuss with your doctor before taking losartan oral tablet.

Boxed warning: Risk of harm if used during pregnancy

Losartan has a boxed warning for the risk of harm if used during pregnancy. Boxed warnings are serious warnings from the Food and Drug Administration (FDA).

For details, see the “Losartan and pregnancy” section below.

Other warnings

It may not be safe for you to take losartan oral tablet if you have specific health conditions. These are sometimes called drug-condition interactions. Other things may also affect whether losartan oral tablet is a safe treatment option for you.

Before taking losartan oral tablet, tell your doctor about your health and medications you take. Things to consider include:

Losartan and pregnancy

You should not take losartan while pregnant. In fact, the drug has a boxed warning for the risk of harm if taken during pregnancy. Boxed warnings are serious warnings from the Food and Drug Administration (FDA).

Risk of harm if taken during pregnancy

Angiotensin II receptor blockers (ARBs), including losartan, should not be taken during pregnancy. Studies have shown that ARBs increase the risk of several types of harm when taken by a pregnant person.

Examples include:

Due to these risks, doctors will not prescribe losartan or any other ARB during pregnancy, except in rare cases.

If you’re taking losartan and become pregnant, immediately stop taking the drug and call your doctor right away. Keep in mind, it’s important to continue treating high blood pressure during pregnancy. This is one of the conditions the drug treats.

Having unmanaged high blood pressure increases the risk of premature birth and complications during delivery. Your doctor can discuss other treatment options with you that are safer to take while you’re pregnant.

Losartan and breastfeeding

You should not breastfeed while taking losartan. It’s not known whether the drug passes into breast milk. But due to the possible risk of harm in a child who is breastfed, breastfeeding while taking losartan is not recommended.

Talk with your doctor to learn more about feeding options besides breastfeeding if you’re taking losartan.

Losartan and alcohol

Losartan oral tablet isn’t known to interact with alcohol.

However, losartan and alcohol can cause similar side effects. Examples include dizziness and low blood pressure when sitting or standing up. Combining the two may raise your risk of these side effects or make them more severe.

If you drink alcohol, talk with your doctor about whether it’s safe to consume it during your treatment with losartan.

What to ask your doctor

This article describes common and serious side effects of losartan oral tablet. If your doctor prescribes this medication, they can discuss possible side effects with you. Let your doctor know if you have concerns or questions about treatment with this medication.

Here’s a list of some possible questions you may want to ask your doctor:

  • How much water should I drink each day if I’m taking losartan plus a diuretic (water pill) such as furosemide (Lasix)?
  • Are there ways to help lower my risk of sun sensitivity while I’m taking losartan?
  • If I have side effects from losartan, can I try taking a lower dose?
  • Does my health history increase my risk of side effects from losartan?

Disclaimer: Optum Perks has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.

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