Olmesartan
Olmesartan lowers blood pressure by blocking angiotensin II receptors. It is used for hypertension when your prescriber selects this ARB. It may be combined with other agents such as a calcium channel blocker or diuretic in fixed-dose tablets.
This medicine is part of the Blood pressure, cholesterol & related category.
Generic name: olmesartan
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?
Olmesartan lowers blood pressure by blocking angiotensin II receptors.
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?
Dizziness, headache, or tiredness may appear early on.
Can you take paracetamol or ibuprofen with it?
NSAIDs, potassium tablets, and some diuretics interact.
More about what Olmesartan is used for
Olmesartan lowers blood pressure by blocking angiotensin II receptors. It is used for hypertension when your prescriber selects this ARB.
It may be combined with other agents such as a calcium channel blocker or diuretic in fixed-dose tablets.
How does Olmesartan work, and how long does it take to work?
Vasodilation and reduced hormonal effects on vessels lower pressure over days of regular use.
Dose adjustments follow clinic measurements and blood tests.
How and when should you take Olmesartan?
Usually once daily, with or without food. Swallow tablets whole.
If you use a combination product, do not split tablets unless the label says they are scored for it.
What are the common side effects of Olmesartan?
Dizziness, headache, or tiredness may appear early on. Gut symptoms such as diarrhoea are uncommon but should be reported if severe or prolonged.
Raised potassium is possible.
Serious side effects of Olmesartan — when to get urgent help
Seek urgent help for severe allergic swelling, fainting with injury, or pregnancy if on olmesartan.
Severe chronic diarrhoea and weight loss have rarely been linked to olmesartan in product literature — report ongoing symptoms.
What if you miss a dose of Olmesartan?
Take when remembered unless nearly time for the next dose; do not double.
Who should not take Olmesartan?
Pregnancy, certain kidney artery problems, and some potassium disorders need alternatives.
Discuss all medicines before surgery.
Can you take paracetamol or ibuprofen with Olmesartan? — other interactions
NSAIDs, potassium tablets, and some diuretics interact. Lithium requires caution.
Olmesartan in pregnancy and breastfeeding
Avoid in pregnancy. Ask your prescriber about breastfeeding.
Blood tests and monitoring on Olmesartan
Kidney function and electrolytes may be checked after starting and periodically.
What might your GP prescribe instead of Olmesartan?
Other ARBs or different antihypertensive classes may suit you if olmesartan is not tolerated.
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Frequently asked questions about Olmesartan
People also ask — common Google searches
- What is Olmesartan used for?
- Olmesartan lowers blood pressure by blocking angiotensin II receptors. It is used for hypertension when your prescriber selects this ARB. It may be combined with other agents such as a calcium channel blocker or diuretic in fixed-dose tablets.
- How long does Olmesartan 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 Olmesartan with paracetamol or ibuprofen?
- NSAIDs, potassium tablets, and some diuretics interact.
- What are the side effects of Olmesartan?
- Dizziness, headache, or tiredness may appear early on. Gut symptoms such as diarrhoea are uncommon but should be reported if severe or prolonged. See the sections below for more detail, including serious side effects and when to seek urgent help.
- Does olmesartan cause a cough like ramipril?
- ACE inhibitors such as Ramipril more often cause cough; ARBs like olmesartan are sometimes used when cough is troublesome, though any new cough should still be reviewed.
- Can olmesartan be taken at night?
- Many people take it once daily at a consistent time that suits them — follow your prescription label unless your prescriber advises otherwise.
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