Losartan Medications

Losartan is an angiotensin II receptor blocker (ARB) that lowers blood pressure by preventing the hormone angiotensin II from binding to its AT₁ receptors. Approved originally for hypertension, the drug is also indicated for heart failure, protection of kidney function in type 2 diabetes, and reduction of stroke risk in patients with left-ventricular hypertrophy. It is marketed worldwide under brand names such as Cozaar and Hyzaar, while generic formulations are widely available. Off-label, clinicians sometimes employ losartan to mitigate proteinuria in chronic kidney disease when other options are unsuitable.

What is Losartan?

Losartan belongs to the class of selective angiotensin II type 1 receptor antagonists. The U.S. Food and Drug Administration first approved it in 1995 for hypertension, and the European Medicines Agency followed with the same indication the next year. Singapore’s Health Sciences Authority (HSA) granted registration in 1999, allowing both branded and generic versions to be dispensed locally. By blocking AT₁ receptors, losartan interrupts the vasoconstrictive and aldosterone-secreting actions of angiotensin II, producing vasodilation and reduced sodium-water retention. The molecule is a biphenyl tetrazole derivative, supplied as tablets that can be purchased through our online pharmacy or any licensed pharmacy in Singapore.

How Losartan Works

Mechanism of Action

Losartan competitively inhibits the binding of angiotensin II to AT₁ receptors located on vascular smooth-muscle cells, adrenal glands, and the renal tubules. This blockade prevents the downstream signaling cascade that normally leads to vasoconstriction, aldosterone release, and sympathetic activation.

Therapeutic Effects

The interruption of angiotensin II signaling results in arterial dilation, lowered systemic vascular resistance, and modest diuresis due to decreased aldosterone-mediated sodium reabsorption. Clinically, this translates into reduced systolic and diastolic blood pressure, decreased after-load on the heart, and attenuation of remodeling processes in the myocardium and kidneys.

Onset and Duration

Peak plasma concentrations are reached 1-2 hours after oral administration, and blood-pressure reduction can be observed within 2 hours. Steady-state effects are typically attained after 3-4 days of once-daily dosing. The antihypertensive effect persists for at least 24 hours, supporting once-daily regimens for most patients.

Approved Uses and Applications

Approved Indications

• Essential hypertension - first-line therapy per HSA and international guidelines.
• Heart failure with reduced ejection fraction - improves morbidity when added to standard therapy.
• Diabetic nephropathy - slows progression of proteinuria and preserves glomerular filtration rate, as shown in the RENAAL trial (NEJM, 2001).
• Stroke risk reduction - indicated for patients with left-ventricular hypertrophy, based on data from the LIFE study (Lancet, 2002).

Off-Label Uses

Losartan is occasionally used to manage hypertension in patients intolerant of ACE inhibitors, and to reduce proteinuria in non-diabetic chronic kidney disease. These applications lack formal regulatory approval but are supported by peer-reviewed case series and small randomized trials.

Clinical Efficacy

In the landmark RENAAL trial, losartan reduced the risk of doubling serum creatinine by 25 % compared with placebo (p < .001). The LIFE study demonstrated a 13 % relative risk reduction in stroke among losartan-treated participants versus atenolol (p = .02).

Buying Losartan from Our Online Pharmacy

Why Choose Our Service

Accessing losartan in Singapore can be challenging for patients without a local prescription or those seeking cost-effective options. Our pharmacy service bridges that gap by delivering verified medication directly to your doorstep, while maintaining strict privacy standards.

Brand Names and Generic Options

Common branded products include Cozaar® (100 mg) and Hyzaar® (combination of losartan 50 mg and hydrochlorothiazide 12.5 mg). Generic losartan tablets are chemically identical and typically cost 30-45 % less than the branded versions.

Quality & Safety

We partner with licensed international pharmacies that comply with WHO Good Manufacturing Practice (GMP) standards, ensuring each shipment meets rigorous quality controls.

Pricing & Access

Competitive pricing starts at SGD 12 per 30-tablet pack of generic 50 mg tablets. Returning customers enjoy a Lifetime 10 % discount on all reorders.

Discreet Delivery

Orders are packaged in unmarked, tamper-evident envelopes. Express shipping arrives in approximately 7 days, while standard delivery takes up to 3 weeks, both with full tracking.

Dosing, Formulations & Administration

Available Formulations

Losartan is supplied as immediate-release tablets in strengths of 25 mg, 50 mg, and 100 mg. Fixed-dose combinations with hydrochlorothiazide are also marketed.

Typical Dosing Ranges

For hypertension, clinicians often start adults at 50 mg once daily; the dose may be increased to 100 mg based on response and tolerability. In heart failure, the initial dose may be 12.5 mg twice daily, titrated upward to a target of 150 mg per day. For diabetic nephropathy, 100 mg once daily is common. All dosing decisions should be individualized by a qualified healthcare professional.

Administration Guidelines

Losartan can be taken with or without food; however, taking the tablet with a full glass of water helps ensure consistent absorption. Patients on potassium-sparing diuretics should have serum potassium monitored regularly.

A healthcare provider must determine the exact regimen after evaluating the patient’s medical history, concomitant drugs, and laboratory values.

Safety Profile & Considerations

Common Side Effects

• Dizziness (≈ 15 % of patients)
• Upper-respiratory tract infection (≈ 10 %)
• Back pain (≈ 8 %)
• Hyperkalemia (> 5 mmol/L) observed in 5-7 % of users, especially when combined with potassium-rich diets or supplements

Serious Adverse Events

Angioedema, though rare (< .1 %), requires immediate medical attention. Acute renal failure may occur in patients with bilateral renal artery stenosis.

Contraindications

• Pregnancy (category D) - losartan can cause fetal toxicity.
• Bilateral renal artery stenosis - risk of renal insufficiency.

Drug Interactions

• Potassium-sparing agents (spironolactone, amiloride) - increase risk of hyperkalemia.
• Non-steroidal anti-inflammatory drugs (NSAIDs) - may blunt antihypertensive effect and worsen renal function.
• Lithium - elevated lithium levels; monitoring required.
• ACE inhibitors - concurrent use raises the likelihood of angioedema and renal impairment; generally avoided.

Special Populations

• Pregnancy & breastfeeding: Losartan is contraindicated in pregnancy; minimal amounts are excreted in breast milk, but breastfeeding is discouraged.
• Elderly: Age-related decline in renal function warrants starting at the lower end of dosing ranges.
• Renal impairment: Dose should be reduced in patients with creatinine clearance < 30 mL/min.
• Hepatic dysfunction: No dose adjustment is needed, as losartan is primarily excreted unchanged via the kidneys.

Frequently Asked Questions

• How does losartan differ from ACE inhibitors? Losartan blocks the AT₁ receptor downstream of angiotensin II, whereas ACE inhibitors prevent the formation of angiotensin II itself. This mechanism avoids the persistent dry cough often seen with ACE inhibitors and carries a lower risk of angioedema.

• How long before losartan produces noticeable blood-pressure reduction? Most patients experience a measurable drop in systolic pressure within 2 hours of the first dose, with maximal effect achieved after 3-4 days of consistent daily dosing.

• What should I do if I develop a persistent cough while taking losartan? Cough is uncommon with ARBs, but if it occurs, contact your clinician. They may evaluate for other causes or consider switching to an alternative antihypertensive class.

• Can losartan be taken with potassium-rich foods or supplements? Yes, but regular monitoring of serum potassium is advisable, especially if you also use potassium-sparing diuretics or supplements.

• Does ibuprofen interfere with losartan’s effectiveness? NSAIDs like ibuprofen can reduce the antihypertensive effect of losartan and increase the risk of kidney injury. Use the lowest effective NSAID dose for the shortest duration, and discuss alternatives with your provider.

• What is the recommended dose of losartan for protecting kidney function in diabetes? Clinical guidelines often suggest 100 mg once daily, but the exact dose should be individualized based on blood pressure targets, renal function, and tolerability.

• Should I take losartan with food? Food does not significantly affect absorption, so you may take it with or without meals. Consistency-taking it at the same time each day-helps maintain stable blood levels.

• What happens if I miss a dose? Take the missed tablet as soon as you remember, unless it is near the time of your next scheduled dose. In that case, skip the missed dose and resume your regular schedule; do not double-dose.

• Can losartan cause dizziness, and is it dangerous? Dizziness is a common side effect, especially when standing up quickly. It usually resolves as your body adjusts, but if it persists or leads to falls, inform your clinician for possible dose adjustment.

• What information should I provide my doctor when discussing losartan?

  • Complete list of current medications, including over-the-counter drugs and supplements.
  • History of kidney disease, liver function, or electrolyte abnormalities.
  • Any previous reactions to ACE inhibitors or ARBs.
  • Your blood-pressure goals and any cardiovascular risk factors.

Disclaimer

The information provided about losartan is for general knowledge only. It does not replace professional medical consultation or the official prescribing information for medications containing this ingredient. All treatment decisions, including dosing, formulation selection, and monitoring, should be made under the supervision of a qualified healthcare provider who can assess individual medical history, current medications, and specific health needs. We assume all readers are responsible adults capable of making informed decisions about their health. Our online pharmacy offers access to medications containing losartan for individuals who may have limited availability through traditional pharmacies, prescription-based insurance schemes, or who are seeking affordable generic alternatives. Always consult your doctor before starting, changing, or discontinuing any medication containing losartan.

External Resources about Losartan

• Losartan: Uses, Dosage, Side Effects, Warnings - Drugs.com
• Losartan potassium - DrugBank Online
• Losartan: MedlinePlus Drug Information
• Losartan Related Compound A USP Reference Standard Sigma …
• Losartan Overview - Active Ingredient - RxReasoner