Uses
What is losartan used for?
Losartan is commonly used for the following conditions.
- To lower high blood pressure (hypertension)
- To lower the risk of stroke in people with high blood pressure and left ventricular hypertrophy, which is a type of heart problem
- To protect the kidneys in people with type 2 diabetes and nephropathy, which is a type of kidney disease
Black people with both high blood pressure and left ventricular hypertrophy may not have a lower risk of stroke with losartan.
Losartan may also be used for other conditions as determined by your healthcare provider.
How does losartan work (mechanism of action)?
Losartan blocks receptors in your body that normally bind to a hormone called angiotensin II. When angiotensin II binds to these receptors, it causes your blood vessels to constrict. Blocking these receptors help your blood vessels relax so that blood can move through them more easily. This can help lower blood pressure and prevent damage to your heart and kidneys.
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How is losartan supplied (dosage forms)?
Losartan is available as Cozaar and generic losartan in the following dosage forms that are taken by mouth.
- 25 mg oral tablets
- 50 mg oral tablets
- 100 mg oral tablets
How should I store losartan?
Losartan should be stored at room temperature, between 68 F to 77 F (20 C to 25 C). It can be exposed to temperatures between 59 F to 86 F (15 C to 30 C), for shorter periods of time, such as when transporting it. Store in a cool, dry place, in a tightly closed container. Protect from light.
Side Effects
What are the most common side effects of losartan?
The most common losartan side effects are listed below. Tell your healthcare provider if you have any of these side effects that bother you.
- Dizziness
- Infection in the nose or throat, sore throat, or common cold symptoms
- Stuffy nose
- Back pain
There may be other side effects of losartan that are not listed here. Contact your healthcare provider if you think you are having a side effect of a medicine. In the U.S., you can report side effects to the FDA at www.fda.gov/medwatch or by calling 800-FDA-1088. In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.
What are the serious side effects of losartan?
While less common, the most serious side effects of losartan are described below, along with what to do if they happen.
Decreased Blood Pressure (Hypotension). Losartan may cause low blood pressure in people with low levels of fluids or salt. This can happen especially in people taking a medicine that causes you to pee more often (diuretic). Tell your healthcare provider right away if you have any of the following symptoms of low blood pressure.
- Dizziness, feeling lightheaded, or fainting
- Confusion
- Feeling weak or tired
Kidney Damage. Kidney damage can happen when taking losartan. Call your healthcare provider right away if you have any of the following symptoms of kidney damage.
- Reduced need to pee
- Swelling in your feet, ankles, or legs
- Weakness or unusual tiredness
- Difficulty catching your breath or chest pain/pressure
- Confusion
- Nausea
- Seizures
High Potassium Level (Hyperkalemia). Losartan can cause a high potassium level (hyperkalemia), which can be serious and may lead to death. Your healthcare provider will check your potassium levels, especially if you take certain other medicines. Call your healthcare provider if you have any of the following symptoms of a high potassium level.
- Weakness or unusual tiredness
- Unusual or slow heartbeat
- Nausea or vomiting
- Trouble breathing
Severe Allergic Reactions. Losartan may cause allergic reactions, which can be serious. Stop using losartan and get help right away if you have any of the following symptoms of a serious allergic reaction.
- Swelling of the face, lips, mouth, tongue, or throat
- Trouble swallowing or throat tightness
- Breathing problems or wheezing
- Racing heart
- Fever or general ill feeling
- Swollen lymph nodes
- Itching, skin rash, or pale red bumps on the skin called hives
- Nausea or vomiting
- Dizziness, feeling lightheaded, or fainting
- Stomach cramps
- Joint pain
Warnings & Precautions
Who should not use losartan?
Allergies to Ingredients. People who are allergic to any of the following should not take losartan.
- Losartan
- Cozaar
- Any of the ingredients in the specific product dispensed
Your pharmacist can tell you all of the ingredients in the specific losartan products they stock.
Drug Interactions. Losartan should not be taken while you are using certain other medicines. Before taking losartan, tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.
What should I know about losartan before using it?
Do not take losartan unless it has been prescribed to you by a healthcare provider. Take it as prescribed.
Do not share losartan with other people, even if they have the same condition as you. It may harm them.
Keep losartan out of the reach of children.
Losartan can affect your alertness or coordination. Do not drive or do other activities that require alertness or coordination until you know how losartan affects you.
Your pharmacist can make a liquid form of this medicine. If you take this form, keep it refrigerated, between 36 F to 46 F (2 C to 8 C), for up to 4 weeks. Before each use, shake the liquid medicine. Use an accurate measuring device to measure your dose. A household spoon is not an accurate measuring device and may cause you to take the wrong dose. Ask your pharmacist to recommend an appropriate measuring device.
What should I tell my healthcare provider before using losartan?
Tell your healthcare provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them determine if losartan is right for you.
In particular, make sure that you discuss any of the following.
Current and Past Health Conditions. Tell your healthcare provider if you have any of the following.
- Heart problems
- Kidney problems
- Liver problems
- Persistent or severe vomiting or diarrhea
Pregnancy. Losartan can cause death or serious harm to an unborn baby if taken during pregnancy. Tell your healthcare provider if you are or plan to become pregnant. If you become pregnant, stop taking losartan right away and contact your healthcare provider.
Breastfeeding. It is not known if losartan passes into breast milk. Tell your healthcare provider if you are breastfeeding or plan to breastfeed. Your healthcare provider will advise you if you should stop breastfeeding or stop losartan.
Interactions
Does losartan interact with foods or drinks?
There are no known interactions between losartan and foods or drinks.
It is unknown if drinking alcohol will affect losartan. The risk of dizziness may be increased if you drink alcohol while taking losartan.
Does losartan interact with other medicines (drug interactions)?
Always tell your healthcare provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.
In particular, make sure that you discuss if you are using any of the following before taking losartan.
- Aliskiren (Tekturna), which is a medicine for high blood pressure
- A supplement or salt-substitute containing potassium
- A diuretic, also called a water pill, which is a medicine used to reduce edema (fluid retention) and blood pressure
- A nonsteroidal anti-inflammatory drug (NSAID), such as ibuprofen, naproxen, and others, which are contained in many prescription and OTC products for pain, swelling, and fever
- Lithium, which is a medicine for certain mental health conditions
- An angiotensin-converting enzyme (ACE) inhibitor, which is a medicine for high blood pressure, heart failure, and certain kidney problems
- An angiotensin II receptor blocker (ARB), which is a medicine for high blood pressure, heart failure, and other heart conditions
- Any medicine for high blood pressure
Overdose/Missed Dose
What should I do if I accidentally use too much losartan?
If you or someone else has used too much losartan, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.
What should I do if I miss a dose of losartan?
If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and only take the next dose. Do not take double or extra doses.
Are you currently using Losartan (Cozaar)?
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