Losartan
NHS information about the medicine losartan, including what it's used for, who can use it, how to use it and side effects.
What losartan is for
Losartan is mainly used to manage high blood pressure (hypertension).
It's a type of medicine called an angiotensin receptor blocker (ARB).
It’s also used to help treat:
- heart failure
- kidney disease caused by type 2 diabetes
How to take losartan
Losartan comes as tablets that you swallow.
How much you need to take and for how long depends on why you're taking it, but you'll usually need to take it long-term.
Most people need to take losartan once a day. Your dose may need to be changed after you've been taking it for several weeks. Do not stop taking losartan unless your doctor tells you to.
When taking losartan:
- take it at any time of day, but try to take it at the same time every day
- take it with water, with or without food
Always check the packet or leaflet that comes with your medicine. Ask a pharmacist or doctor for advice if you're not sure how to take it or have any problems taking it.
Your doctor will arrange for you to have blood tests and blood pressure checks while you’re taking losartan, to check how it’s affecting your blood pressure and kidneys.
If you get ill with vomiting, diarrhoea or high temp when taking bumetanide, there's a risk you'll get dehydrated.
Talk to a pharmacist or doctor for advice, or follow the advice they've already given you.
If you miss a dose of losartan
If you forget to take a dose of losartan, take the next dose as normal.
Do not take 2 doses to make up for a missed dose.
If you take too much losartan
Taking too much losartan can be dangerous.
Side effects of losartan
Like all medicines, losartan can cause side effects, but not everyone gets them.
Common side effects
Common side effects of losartan can include:
- dizziness
- tiredness
- headache
- tummy pain
- feeling sick (nausea) or being sick (vomiting)
- swelling in your legs, ankles or feet (oedema)
Losartan should not affect your ability to drive, ride a bike or use machinery. However, if you feel dizzy or tired while taking it, wait until you no longer have these side effects.
These are not all the side effects of losartan.
For a full list, see the leaflet that came with your medicine or search for your medicine leaflet on the electronic medicines compendium website.
You can report any side effects you get on the Yellow Card website.
Who can and cannot take losartan
Most adults aged 18 years or over can take losartan. Losartan may also be suitable for children aged 6 to 17 years old.
Losartan is not suitable for some people. For example, it may not be suitable if:
- you've had an allergic reaction to other ARB medicines
- you have severe heart failure
- you have problems with your liver
- you've had a condition called angioedema in the past, which is where parts of your body swell suddenly
Before taking losartan, tell your doctor if you have any medical conditions.
Breastfeeding and losartan
Tell your doctor if you're breastfeeding. Losartan is not usually used while breastfeeding. You doctor may offer a different treatment while you're breastfeeding.
Pregnancy and losartan
Tell your doctor if you're pregnant or trying to get pregnant. Losartan is not usually used during pregnancy. Your doctor may offer you different treatment while you're pregnant.
Taking losartan with other medicines, food and drink
There are some medicines and supplements that may not mix well with losartan.
This includes:
- other medicines used to treat high blood pressure, including beta blockers and ACE inhibitors like lisinopril
- some medicines that remove excess fluid in your body through your pee (diuretics), such as spironolactone
- supplements and salt substitutes (used to flavour food) that contain potassium
- some non-steroidal anti-inflammatory drugs (NSAIDs), including ibuprofen
- fluconzanole (an antifungal commonly used to treat thrush)
- tricyclic antidepressants, such as amitriptyline
- antipsychotic medicines, such as quetiapine
- lithium (used to treat some mental health problems)
This is not the full list of medicines that may not mix well with losartan. Before taking it, tell your doctor if you’re taking any other medicines, herbal remedies, vitamins or supplements.
Food, drink and alcohol with losartan
You can generally eat as normal while taking losartan, but avoid drinking grapefruit juice because it can stop your medicine working properly.
Try to limit the amount of alcohol you drink while taking losartan because it can increase the risk of side effects.
Find out more about your medicine
To find out more about your medicine, you can:
- check the leaflet that comes with it
- search for your medicine leaflet on the electronic medicines compendium website
- speak to a pharmacist or doctor for advice
