Losartan
Losartan is an angiotensin II receptor blocker (ARB). It is commonly prescribed for high blood pressure and may be used to protect the kidneys in some people with diabetes and protein in the urine, when your clinician judges it appropriate.
This medicine is part of the Blood pressure, cholesterol & related category.
Generic name: losartan
Quick answers
Short replies to searches people often run before speaking to a clinician. For the overview of what the medicine is used for, see the short summary under the page title above.
What is it for?
Losartan is an angiotensin II receptor blocker (ARB).
How long does it take to work?
Blood pressure can fall over days to weeks after starting or changing dose; attend follow-up checks your GP arranges.
What are common side effects?
Possible effects include dizziness (especially when standing), tiredness, or mild stomach upset.
Can you take paracetamol or ibuprofen with it?
Losartan can interact with potassium supplements, potassium-sparing diuretics, NSAIDs, and some other blood pressure drugs.
Compare this medicine
Side-by-side guides and related reads — use these links for fuller context; they do not mean you should switch treatment yourself.
- Ramipril vs Losartan — side-by-side guide
More about what Losartan is used for
Losartan is an angiotensin II receptor blocker (ARB). It is commonly prescribed for high blood pressure and may be used to protect the kidneys in some people with diabetes and protein in the urine, when your clinician judges it appropriate.
Your GP or pharmacist may explain how it fits with other cardiovascular medicines and lifestyle advice.
How does Losartan work, and how long does it take to work?
ARBs block the action of a hormone that narrows blood vessels, helping vessels relax and blood pressure fall. The effect builds with regular use.
Unlike ACE inhibitors, ARBs do not usually cause the same dry cough, though individual responses vary.
How and when should you take Losartan?
Losartan is often taken once daily, with or without food. Swallow tablets with water and follow the strength on your label.
Do not change your dose or stop without speaking to your GP, especially if you have heart or kidney disease.
What are the common side effects of Losartan?
Possible effects include dizziness (especially when standing), tiredness, or mild stomach upset. Many people tolerate losartan well.
Report persistent or troublesome symptoms to your GP or pharmacist.
Serious side effects of Losartan — when to get urgent help
Seek urgent help for swelling of the face, lips, or tongue; difficulty breathing; severe dizziness; or a high fever with rash.
If you become dehydrated (vomiting, diarrhoea), contact your GP — blood pressure and kidney function may need review.
What if you miss a dose of Losartan?
If you miss a dose, take it when you remember unless your next dose is due soon. Do not double up.
Your pharmacist can advise if you are unsure how to catch up.
Who should not take Losartan?
Losartan is not used in pregnancy. If you could become pregnant, discuss contraception and planning with your prescriber.
Your doctor will consider kidney problems, narrowing of kidney arteries, and potassium supplements before prescribing.
Can you take paracetamol or ibuprofen with Losartan? — other interactions
Losartan can interact with potassium supplements, potassium-sparing diuretics, NSAIDs, and some other blood pressure drugs. This list is not exhaustive.
Always mention all medicines and herbal products when prescriptions are reviewed.
Losartan in pregnancy and breastfeeding
ARBs are avoided in pregnancy due to risk to the baby. If you think you may be pregnant, contact your GP promptly.
Breastfeeding advice is individual; your GP or pharmacist can guide you.
Blood tests and monitoring on Losartan
Blood tests for kidney function and potassium are often done when starting losartan and after dose changes.
Home blood pressure readings may be suggested as part of your care plan.
What might your GP prescribe instead of Losartan?
Your GP may consider ACE inhibitors (such as Ramipril), other ARBs, calcium channel blockers, or beta-blockers if losartan is not suitable.
Choices depend on your overall health and other medicines.
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Frequently asked questions about Losartan
People also ask — common Google searches
- What is Losartan used for?
- Losartan is an angiotensin II receptor blocker (ARB). It is commonly prescribed for high blood pressure and may be used to protect the kidneys in some people with diabetes and protein in the urine, when your clinician judges it appropriate.
- How long does Losartan take to work?
- Blood pressure can fall over days to weeks after starting or changing dose; attend follow-up checks your GP arranges. Always follow your prescriber’s follow-up plan.
- Can you take Losartan with paracetamol or ibuprofen?
- Losartan can interact with potassium supplements, potassium-sparing diuretics, NSAIDs, and some other blood pressure drugs.
- What are the side effects of Losartan?
- Possible effects include dizziness (especially when standing), tiredness, or mild stomach upset. Many people tolerate losartan well. See the sections below for more detail, including serious side effects and when to seek urgent help.
- Losartan vs ramipril — what is the difference?
- Ramipril is an ACE inhibitor; losartan is an ARB. Both lower blood pressure but work in different ways. ACE inhibitors may cause a dry cough; ARBs often do not. Your prescriber chooses what suits you.
- Does losartan protect the kidneys?
- In some people with diabetes and kidney involvement, prescribers use ARBs for organ protection as part of a care plan. This is decided individually with blood tests and reviews.
Need personalised advice?
Your local pharmacist or GP surgery can help with questions about your medicines, side effects, and alternatives that may be suitable for you.
Links open the NHS website for finding services. DrugABC does not sell prescription-only medicines or replace clinical care.
Often used with
People searching for Losartan often read about these medicines too — for example when treatments are combined under GP or specialist care. This is not a prescribing suggestion.
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