Losartan
Losartan (often found in brands like Cozaar-comp) acts as a medication to manage high blood pressure and support kidney health. It is associated with well-known options such as Cozaar and Hyzaar. Available in various formulations, it remains a standard option in cardiovascular management.
Key points
- An angiotensin II receptor blocker that also helps protect kidney function in people with type 2 diabetes, beyond lowering blood pressure.
- Should be avoided during pregnancy or in severe liver impairment, and used cautiously with diuretics or anti-inflammatory drugs.
- Potassium supplements and salt substitutes can raise potassium levels further, since the medicine already tends to increase them.
What is Losartan?
Losartan functions as an angiotensin II receptor blocker. It works by relaxing blood vessels, which allows blood to flow with less resistance. Because several commercial brands exist, patients can find variations in formulation and brand names to suit specific treatment plans.
What Losartan is used for
Primary indications for this ingredient include Hypertension and the prevention of Diabetic Nephropathy, which involves guarding kidney function in individuals with type 2 diabetes.
How does Losartan work?
When your body produces a chemical called angiotensin II, blood vessels can tighten, which raises blood pressure. Losartan blocks the receptors that angiotensin II binds to, preventing this tightening response. By keeping vessels open and relaxed, the medication maintains lower blood pressure and eases the workload on your heart.
Losartan brands and forms
While the medical structure of the ingredient remains consistent, manufacturers provide different brand options. Patients often see choices between originator medications and generic versions, which provide the same active compound. You can explore relevant medical products within our Heart & Blood Pressure section. The primary available form is a film-coated tablet for oral intake.
Safety overview for Losartan
What to check before using this medicine
Use of this medication is not suitable if you are pregnant or have a history of severe liver impairment. Interactions with other diuretics or anti-inflammatory drugs are common, as these may alter how the medication performs.
Possible reactions and tolerability
Some individuals experience dizziness, fatigue, or an increase in potassium levels. Persistent symptoms or changes in health status often require a review of the dosage or therapy plan.
Interactions and health factors
Potassium supplements and certain salt substitutes can interact with this medication. Product labelling and verified clinical sources remain the correct references for specific contraindications, interactions and reactions.
Further reading
What is losartan used for?
Losartan is used mainly for hypertension and for the prevention of diabetic nephropathy, which means guarding kidney function in people with type 2 diabetes.
How does losartan work?
Losartan blocks the receptors that angiotensin II binds to, so blood vessels do not tighten as much. This keeps vessels open and relaxed, which maintains lower blood pressure and eases the workload on your heart.
How long does losartan take to work?
Losartan starts working within 1 to 2 weeks, and each dose lasts about 24 hours.
What are the side effects of losartan?
Some people experience dizziness, fatigue or an increase in potassium levels, and hypotension and hyperkalaemia are also possible. Angioedema and renal failure are serious reactions that require immediate medical attention, so speak to a doctor or pharmacist if you notice anything unusual.
Can losartan be taken with other medicines?
Losartan can interact with diuretics and anti-inflammatory drugs, which may alter how the medication works. Potassium supplements and certain salt substitutes can also interact with it, so check with a doctor or pharmacist before combining medicines.
Who should not take losartan?
It is not suitable if you are pregnant or have a history of severe liver impairment. It should also be used cautiously with diuretics or anti-inflammatory drugs.
In which products can I find losartan?
Products containing losartan include Cozaar and Hyzaar. Compare forms, strengths and packs in the listings above.
Which brands contain losartan?
Besides the products listed here, losartan is sold under brand names such as Cozaar-Comp. Names differ from country to country, so the active ingredient is the surest way to compare.
Do I need a prescription for losartan in Thailand?
No. In Thailand losartan is sold by pharmacists without a prescription, and Yasabai does not ask for one either. We are an online store, not a dispensing pharmacy; we arrange your order and delivery on your behalf.
Ordering without a prescription →Can I order losartan online in Thailand?
Yes. Our pharmacy partners ship from India to Thailand and across Asia in discreet packaging. Standard Airmail takes up to 3 weeks; Express Tracked Courier takes up to 1 week.
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