# Losartan in Nigeria

Losartan has 33 active NAFDAC registrations in our October 2026 copy of the register, from 21 registration holders; 55 further listings have lapsed.

- Source: https://ogbogwu.com/drugs/losartan/
- Drug class: Angiotensin II receptor blocker (ARB) (Hypertension)
- Also known as: Cozaar, Losartan potassium
- Prescription required: yes
- On the WHO Model List of Essential Medicines
- Last updated: October 2026

## Price in Nigeria

As of October 2026, Losartan sells for about ₦1,900 online in Nigeria at MedPlus. The online price is roughly unchanged since July 2026. Open-market prices (e.g. Idumota, Ogbogwu) are often lower.

## What is Losartan?

Losartan is an angiotensin II receptor blocker (ARB), a modern class of blood pressure medication that has become increasingly important in the management of hypertension in Nigeria. It works by blocking the action of angiotensin II, a powerful hormone that causes blood vessels to constrict and raises blood pressure. Unlike ACE inhibitors such as lisinopril — which prevent the production of angiotensin II — losartan allows the hormone to be produced but blocks it from binding to its receptors on the blood vessels. The end result is similar: the blood vessels relax, blood pressure comes down, and the workload on the heart is reduced. Hypertension remains one of the most significant public health challenges in Nigeria, affecting an estimated 30-45% of adults, with the vast majority undiagnosed and untreated.

The most significant advantage of losartan over ACE inhibitors is that it does NOT cause the persistent dry cough that plagues many patients on drugs like lisinopril. This cough, which affects up to 10-20% of ACE inhibitor users, is the single most common reason patients in Nigeria are switched from an ACE inhibitor to an ARB like losartan. Like ACE inhibitors, losartan provides important kidney protection in patients with diabetic nephropathy — the kidney damage caused by diabetes — making it an excellent choice for the many Nigerians who suffer from both diabetes and hypertension simultaneously. Losartan has also been shown to reduce the risk of stroke in hypertensive patients, adding another layer of cardiovascular protection.

Losartan is available in Nigeria under brand names including Cozaar (the original Merck brand) and locally manufactured generics. It is taken once daily, making it convenient for long-term use. However, losartan is generally more expensive than ACE inhibitors in Nigeria, which can be a barrier for some patients requiring lifelong treatment. All genuine brands sold in the country must carry valid NAFDAC registration numbers. Like lisinopril, losartan is ABSOLUTELY CONTRAINDICATED in pregnancy due to the risk of serious harm to the unborn baby.

## What is Losartan used for?

- Treatment of hypertension (high blood pressure) — often the preferred choice when patients cannot tolerate ACE inhibitors due to dry cough
- Protection of the kidneys in patients with type 2 diabetes and diabetic nephropathy — slows the progression of kidney disease
- Management of heart failure — used as an alternative to ACE inhibitors when cough is intolerable, or in combination with other heart failure medications
- Reduction of stroke risk — losartan has been shown to reduce the risk of stroke in patients with hypertension and left ventricular hypertrophy (thickening of the heart muscle)
- Often used in combination with amlodipine or a thiazide diuretic for enhanced blood pressure control in Nigerian patients

## Dosage

Always follow a doctor's or pharmacist's instructions; this is general reference information.

- Adults: For hypertension: the usual starting dose is 50mg taken once daily. If blood pressure is not adequately controlled after several weeks, the dose may be increased to 100mg once daily, or a second antihypertensive (such as amlodipine or hydrochlorothiazide) may be added. For diabetic nephropathy: the usual dose is 50mg once daily, increased to 100mg once daily based on blood pressure response. For patients with liver problems or volume depletion (e.g., from diuretic use), a lower starting dose of 25mg once daily is recommended. Take losartan at the same time each day, with or without food.
- Children: Losartan may be used in children aged 6 years and older for hypertension. The starting dose is typically 0.7mg/kg once daily (up to 50mg). Paediatric dosing must be determined and monitored by a specialist. It is not recommended for children under 6 years or children with significant kidney impairment.
- Elderly: No specific dose adjustment is required for elderly patients solely based on age. However, elderly patients often have reduced kidney function, and a lower starting dose of 25mg may be appropriate. Regular monitoring of kidney function and potassium levels is advisable.

Losartan must be taken every day, even when you feel well. Hypertension is a lifelong condition, and stopping medication when blood pressure readings appear normal is one of the most dangerous mistakes patients make — your blood pressure will rise again without treatment, putting you at risk of stroke, heart attack, and kidney failure. Do NOT stop losartan suddenly without medical advice. If you miss a dose, take it as soon as you remember, but skip it if it is almost time for your next dose. Never take a double dose. Your doctor will periodically check your kidney function and potassium levels through blood tests.

## Side effects

Common: Dizziness or lightheadedness, especially during the first few days of treatment or when the dose is increased; Back pain or muscle pain; Fatigue or tiredness; Nasal congestion or upper respiratory symptoms; Diarrhoea or stomach upset; Elevated potassium levels (hyperkalaemia) — usually detected through blood tests and typically mild.

Serious (seek medical help immediately): Angioedema — sudden swelling of the face, lips, tongue, or throat causing difficulty breathing. Although much less common with ARBs than with ACE inhibitors, it can still occur and is a medical emergency; Severe hypotension (very low blood pressure) — causing fainting or collapse, especially in patients who are volume-depleted from diuretic use, vomiting, or diarrhoea; Acute kidney failure — particularly in patients with pre-existing kidney problems, renal artery stenosis, or those taking NSAIDs concurrently; Dangerously elevated potassium levels (severe hyperkalaemia) — can cause life-threatening abnormal heart rhythms; Rhabdomyolysis (muscle breakdown) — very rare but reported; seek medical attention if you experience severe unexplained muscle pain.

When to see a doctor: Seek EMERGENCY medical attention immediately if you experience swelling of the face, lips, tongue, or throat, or if you have difficulty breathing — although angioedema is less common with losartan than with ACE inhibitors, it remains a potentially life-threatening emergency. See your doctor promptly if you experience persistent dizziness, fainting, significantly reduced urine output, severe muscle pain, or any unusual symptoms. If you become pregnant while taking losartan, contact your doctor IMMEDIATELY as the medication must be stopped urgently.

## Warnings

Do not take if: ABSOLUTELY CONTRAINDICATED IN PREGNANCY — losartan can cause serious birth defects, kidney failure, and death in the unborn baby, particularly in the second and third trimesters. Women of childbearing age must use reliable contraception while taking this medication; Do not take if you have a history of angioedema related to previous ARB or ACE inhibitor use; Do not use in combination with aliskiren in patients with diabetes or moderate-to-severe kidney impairment; Do not take if you are allergic to losartan or any of the tablet ingredients; Use with extreme caution in patients with bilateral renal artery stenosis or stenosis of the artery to a single functioning kidney.

Interactions: Potassium supplements and potassium-sparing diuretics (such as spironolactone) — combining with losartan can cause dangerously high potassium levels; regular blood test monitoring is essential; NSAIDs (such as ibuprofen and diclofenac) — can reduce the blood pressure-lowering effect of losartan and increase the risk of kidney damage. This is particularly important in Nigeria where NSAIDs are commonly purchased without prescription for pain relief; Lithium — losartan can increase lithium levels in the blood to potentially toxic concentrations; ACE inhibitors (such as lisinopril) — combining an ARB with an ACE inhibitor is generally NOT recommended as it increases the risk of hypotension, kidney failure, and hyperkalaemia without additional benefit; Rifampicin and fluconazole — rifampicin may reduce losartan's effectiveness, while fluconazole may increase its levels; inform your doctor about all medications you are taking; Salt substitutes containing potassium — avoid these while taking losartan as they can contribute to dangerous potassium elevation.

Pregnancy & breastfeeding: Losartan is ABSOLUTELY CONTRAINDICATED during pregnancy. Like all drugs that act on the renin-angiotensin system, losartan can cause severe harm to the developing baby, including kidney failure, reduced amniotic fluid, skull and limb defects, and foetal death, especially when used in the second and third trimesters. If you discover you are pregnant while taking losartan, STOP the medication immediately and contact your doctor urgently to be switched to a pregnancy-safe antihypertensive such as methyldopa or labetalol. Women who are planning pregnancy should switch to a safe alternative before conceiving. There is insufficient data on losartan in breast milk, and it is not recommended during breastfeeding. Consult your doctor for a safer alternative if you are nursing.

## Brands in Nigeria

Well-known NAFDAC-registered brands: Cozaar (Merck, made in USA); Emzor Losartan (Emzor, made in Nigeria).
Full searchable brand list: https://ogbogwu.com/drugs/losartan/brands/

## How to verify it is genuine

1. Check the NAFDAC registration number on the packaging — all genuine losartan brands sold in Nigeria must display a valid NAFDAC number (e.g., A4-XXXX or B4-XXXX format)
2. Verify the NAFDAC number using the NAFDAC Green Book or the NAFDAC mobile verification app available on Android and iOS
3. Purchase only from licensed pharmacies and registered patent medicine stores — avoid buying blood pressure medications from unregistered vendors, open markets, or unverified online stores
4. Check the expiry date and ensure the packaging is properly sealed, intact, and shows no signs of tampering, water damage, or repackaging
5. Genuine tablets should have consistent size, shape, colour, and markings. If tablets appear uneven, crumbly, discoloured, or have an unusual smell or taste, do not use them and report to NAFDAC
6. For Cozaar (Merck), look for the distinctive tablet shape, film-coating colour, and embossed markings corresponding to the strength. For Emzor products, verify the holographic security seal and batch number on the outer packaging

Verify any NAFDAC number free (no login): https://ogbogwu.com/nafdac-checker/

## FAQs

### Why would my doctor switch me from lisinopril to losartan?

The most common reason doctors in Nigeria switch patients from lisinopril to losartan is the persistent dry cough caused by ACE inhibitors. This cough affects up to 10-20% of patients on lisinopril and can be very troublesome — keeping patients awake at night and causing significant discomfort. Since losartan works through a different mechanism (blocking angiotensin II receptors rather than ACE), it does NOT cause this cough. Losartan provides very similar benefits to lisinopril — including blood pressure reduction, heart protection, and kidney protection in diabetic patients — without the cough side effect. Other less common reasons for switching include angioedema (swelling) caused by the ACE inhibitor, or simply patient preference. If your doctor switches you, the transition is usually straightforward — you simply stop lisinopril one day and start losartan the next, though your doctor will advise on the specific timing and dosing.

### Can losartan protect my kidneys if I have diabetes?

Yes, kidney protection is one of the most important benefits of losartan for diabetic patients. The RENAAL study, a landmark clinical trial, demonstrated that losartan significantly reduces the progression of diabetic nephropathy (kidney disease caused by type 2 diabetes) and lowers the risk of end-stage kidney disease requiring dialysis. Losartan achieves this by reducing the pressure inside the kidney's filtering units (glomeruli) and by decreasing the amount of protein leaking into the urine (proteinuria), which is a key marker of kidney damage. In Nigeria, where diabetes and hypertension frequently occur together and diabetic kidney disease is a leading cause of kidney failure, this kidney-protective property makes losartan an extremely valuable medication. If you have both diabetes and high blood pressure, your doctor will likely consider losartan (or an ACE inhibitor like lisinopril) specifically because of this kidney protection. Regular monitoring through blood tests and urine tests is essential to track your kidney health.

### Can I take losartan together with amlodipine?

Yes, combining losartan with amlodipine is a well-established and highly effective antihypertensive strategy that is widely used in Nigeria. This combination works particularly well because the two drugs lower blood pressure through completely different mechanisms — amlodipine relaxes the blood vessels by blocking calcium channels, while losartan blocks the angiotensin II system. Together, they provide stronger blood pressure reduction than either drug alone. This combination is especially relevant for Nigerian and Black patients, who often require two or more antihypertensive medications to achieve target blood pressure levels. An added benefit is that losartan can help counteract the ankle swelling that amlodipine sometimes causes. Some pharmaceutical companies produce fixed-dose combination tablets containing both losartan and amlodipine in a single pill, which simplifies the daily medication routine and can improve adherence to treatment — a critical factor in the lifelong management of hypertension.

## Sources

- NAFDAC Greenbook (official register of approved products in Nigeria)
- WHO Model List of Essential Medicines
- British National Formulary (BNF)
- Nigerian Standard Treatment Guidelines (Federal Ministry of Health)