Losartan

What Does Losartan Do?

Losartan is an angiotensin II receptor blocker used to treat high blood pressure, lowering the risk of cardiac events and stroke. It can also treat kidney disease in type 2 diabetes patients, offer kidney protection in high-pressure cases and left ventricular hypertrophy, with off-label uses in migraine prevention and heart failure treatment.

How Does Losartan Work? (the complicated stuff)

Losartan works by blocking the binding of angiotensin II—a potent vasoconstrictor—to its receptor sites, thus preventing vasoconstriction and the release of aldosterone. As a result of this, peripheral resistance, preload, afterload, and blood volume decrease, effectively lowering the blood pressure.

Drug Type and Category of Losartan

Losartan is a small molecule drug that belongs to the angiotensin II receptor blocker (ARB) class.

What dosage of Losartan should you be taking?

NICE Guidelines ¹

Losartan dosage recommendations according to NICE guidelines vary based on the condition being treated. Here are the key points:

Adult Dosage

Hypertension:

• Initial dose: 50 mg once daily.
• Maximum dose: 100 mg once daily, adjusted based on blood pressure response.

Heart Failure:

• Initial dose: 12.5 mg to 50 mg once daily.
• Target dose: 50 mg to 150 mg once daily.

Diabetic Nephropathy:

• Initial dose: 50 mg once daily.
• Maximum dose: 100 mg once daily, depending on the patient's response.

Elderly Patients:

A lower starting dose of 25 mg may be recommended for those over 75 years or with possible intravascular volume depletion.

Paediatric Dosage

For children aged 6 years and older with hypertension:

• Initial dose: 0.7 mg/kg once daily (up to a maximum of 50 mg).

Adjustments

Hepatic Impairment:

• Initial dose: 25 mg for patients with mild to moderate liver dysfunction.

Renal Impairment:

• Dosage adjustments may be necessary based on renal function and volume status.
• Monitoring of blood pressure, renal function, and potassium levels is essential during treatment to ensure safety and efficacy.
  

What are the side-effects of Losartan?

Losartan can cause both common and serious side effects. The most commonly reported side effects include:

• Dizziness
• Upper respiratory infections, such as the common cold
• Stuffy nose
• Back pain
• Diarrhea
• Fatigue
• Chest pain
• Headache
• Itching
• Muscle pain
• Sexual side effects like erectile dysfunction

Serious side effects of losartan are less common but can include:

• High potassium blood levels (hyperkalemia), which can cause heart rhythm problems, muscle weakness, and slow heart rate
• Allergic reactions with swelling of the face, lips, throat, or tongue
• Low blood pressure, causing lightheadedness or fainting
• Kidney damage, leading to reduced urination, swelling, weakness, and difficulty breathing
• Anemia with symptoms like pale skin, lightheadedness, and shortness of breath
• Fetal harm or pregnancy loss if taken during pregnancy.
  

Drug Interactions

• NSAIDs and Aspirin: Non-steroidal anti-inflammatory drugs (NSAIDs) like ibuprofen (Advil, Motrin), naproxen, diclofenac, celecoxib, and etoricoxib can reduce the blood pressure lowering effects of losartan. Aspirin at doses over 3g per day can also interact.
• ACE Inhibitors and ARBs: Other blood pressure medications like ACE inhibitors (enalapril, captopril, lisinopril, ramipril) and ARBs (aliskiren) can have additive effects with losartan, increasing the risk of low blood pressure and high potassium levels.
• Potassium-sparing diuretics like spironolactone, used to treat heart failure, can cause dangerously high potassium levels when combined with losartan.
• Lithium: Losartan may increase blood levels of lithium, used to treat mental health conditions, potentially leading to lithium toxicity.
• Heparin: The anticoagulant heparin may have an increased effect when taken with losartan.

Supplements

Potassium supplements and salt substitutes containing potassium should be avoided with losartan due to the risk of hyperkalemia.

Natural Alternatives to Losartan

The best way to reduce blood pressure is to exercise and keep your weight at a healthy normal. Keeping low stress levels is also helpful for reducing blood pressure. Maintaining a good diet, exercising regularly, and living a healthy life are essential ways to naturally help reduce high blood pressure. 

Natural alternatives to losartan can include various foods, herbs, and supplements that may help manage hypertension. Here are some notable options:

Natural Sources of Beta-Blockers

1. Garlic: Contains allicin, which has been shown to lower blood pressure and improve heart health. ^2,3
2. Hibiscus: Often used in traditional medicine, hibiscus tea has been found to reduce blood pressure by enhancing nitric oxide production and acting as a diuretic. ²
3. Hawthorn: This herb is traditionally used for cardiovascular health and may help in lowering blood pressure. ³
4. Indian Snakeroot (Rauwolfia serpentina): Known for its antihypertensive properties, it has been used in traditional medicine for managing high blood pressure. ³
5. Omega-3 Fatty Acids: Found in fatty fish like salmon and supplements, omega-3s can help reduce blood pressure and improve overall heart health. ^3,4
6. Potassium: Adequate potassium intake can help lower blood pressure. Foods rich in potassium include bananas, potatoes, and low-fat dairy products. ^3,4
7. L-arginine: An amino acid that promotes the production of nitric oxide, helping to relax blood vessels and lower blood pressure. Sources include nuts, seeds, and leafy greens. ³
8. Coenzyme Q10 (CoQ10): This antioxidant may support heart health and has been linked to lower blood pressure levels. ^3,4

Lifestyle Considerations

Incorporating these natural alternatives into a balanced diet may provide supportive benefits for blood pressure management. However, it is crucial to consult with a healthcare professional before making any changes to medication or treatment plans, especially for those currently taking losartan or other antihypertensive medications. 

Interesting facts about Losartan

Besides its antihypertensive effects, losartan also acts as a uricosuric agent, meaning it helps to lower uric acid levels in the blood. This can be beneficial for patients with gout or high uric acid levels. 

Unlike ACE inhibitors, which can cause a persistent dry cough, Losartan does not usually cause this side effect. This makes it a good alternative for patients who cannot tolerate ACE inhibitors.

Disclaimer

This article is generated for informational purposes only. It was created in December 2024. Medications and medical guidance can change over time. Therefore, it is essential to consult with your general practitioner or healthcare provider before making any decisions regarding medications or treatment plans. Your GP can provide personalised advice based on your specific health needs and conditions.

References:

1. https://bnf.nice.org.uk/drugs/losartan-potassium/
2. https://www.medicalnewstoday.com/articles/natural-beta-blockers
3. https://www.healthline.com/health/natural-beta-blockers
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3989080/