Losartan vs. valsartan: Differences, similarities, and which is better for you

Drug overview & main differences | Conditions treated | Efficacy | Insurance coverage and cost comparison | Side effects | Drug interactions | Warnings | FAQ

Losartan and valsartan are generic prescription drugs used to treat hypertension, also known as high blood pressure. They are both included in the same class of drugs called angiotensin II receptor blockers (ARBs), and they work by blocking the actions of angiotensin II, a hormone molecule that causes blood vessels to constrict. By blocking the actions of angiotensin II, ARBs relax the blood vessels to allow blood to flow more easily and reduce blood pressure. 

While losartan and valsartan work in identical ways, they have some differences in how they’re used. They also have slight differences in side effects. Continue reading to learn more about the differences and similarities between losartan and valsartan.

What are the main differences between losartan vs. valsartan

Active ingredients

Losartan and valsartan are ARB medications used for high blood pressure. However, they contain different active ingredients and have different brand names. Losartan is available under the brand name Cozaar and valsartan is available under the brand name Diovan.

Metabolism

Losartan, also known as losartan potassium, is a prodrug that is converted to an active form (metabolite) in the liver. The active metabolite provides most of the drug’s blood pressure lowering effects and reaches peak levels in the blood within three to four hours. Effects of the drug generally last for up to 24 hours, although the exact duration of action can vary based on the dosage prescribed. 

Valsartan is not a prodrug. It does not need to be converted into an active metabolite to provide maximal blood pressure lowering effects. Peak levels of valsartan are reached within two to four hours, and antihypertensive effects typically last for around 24 hours. 

Strengths and dosage

Losartan is available as an oral tablet in strengths of 25 mg, 50 mg, and 100 mg. The usual starting dose in adults for hypertension is 50 mg once daily, which can be increased or decreased depending on the person’s response to treatment. People with liver problems may start losartan on a lower dose than usual.

Valsartan is available as an oral tablet in strengths of  40 mg, 80 mg, 160 mg, and 320 mg. The starting dose in adults for hypertension is 80 or 160 mg once daily, and the usual dose range is 80 to 320 mg once daily. The strength and dosage may vary depending on the condition being treated. In some cases, valsartan may be prescribed to be taken twice daily. No dose adjustments are needed for people with liver problems. 

Conditions treated by losartan and valsartan

Losartan is FDA approved to treat hypertension in adults and children who are 6 years of age or older. It is also approved to treat diabetic nephropathy, a type of kidney disease, in people with type 2 diabetes and hypertension. In addition, losartan can help reduce the risk of stroke in people with hypertension and left ventricular hypertrophy (an enlarged heart). 

Like losartan, valsartan is FDA approved to treat hypertension in adults and children who are at least 6 years of age. However, valsartan is also approved to treat heart failure and reduce the risk of hospitalization in people with congestive heart failure. Valsartan may be prescribed to reduce the risk of death after a heart attack. 

Is losartan or valsartan more effective?

According to data from a randomized, clinical trial, 50 mg of losartan and 80 mg of valsartan are similarly effective for treating hypertension. The trial included almost 500 hypertensive patients and compared the effects of losartan and valsartan over 12 weeks. Results of the study found that the average change in sitting diastolic blood pressure did not significantly differ between people taking 50 mg of losartan or 80 mg of valsartan daily.

Valsartan may be more effective than losartan at doses of 160 mg or 320 mg daily. One meta-analysis found that 160 mg or 320 mg of valsartan daily is more effective than 100 mg of losartan daily at lowering blood pressure. This analysis, published in the International Journal of Clinical Practice, included 31 randomized, clinical trials. 

The most appropriate medication will depend on the condition being treated, other medical conditions a person has, and other medications a person may be taking. Consult with a healthcare provider to determine the most appropriate treatment option. 

Coverage and cost comparison of losartan vs. valsartan

The average retail price of losartan is $71.25 for a 30-day supply of 50 mg tablets. The cash price can vary depending on the dosage and quantity prescribed. Insurance plans generally cover the cost of losartan. Uninsured and underinsured patients may be able to use a SingleCare losartan coupon to help reduce the cash price of losartan to less than $10. 

The average retail price of valsartan is $136.53 for a 30-day supply of 160 mg tablets. The cash price can vary depending on the dosage and quantity prescribed. Most insurance plans will help cover the cost of valsartan. A SingleCare valsartan coupon may help reduce the cash price of valsartan to less than $10. 

Common side effects of losartan vs. valsartan

The most common side effects of losartan are dizziness, nasal congestion, upper respiratory tract infections, and back pain. Other side effects may include fatigue, abdominal pain, diarrhea, joint pain, and cough. 

The most common side effects of valsartan are headache, dizziness, viral infections, fatigue, and abdominal pain. Other possible side effects include diarrhea, back pain, and cough. 

Frequency is not based on data from a head-to-head trial. This may not be a complete list of adverse effects that can occur. Please refer to your doctor or healthcare provider to learn more.

Source: DailyMed (Losartan), DailyMed (Valsartan)

Drug interactions of losartan vs. valsartan

Losartan and valsartan interact with the same types of drugs. 

Taking an ARB with lithium can increase the risk of lithium toxicity. Lithium levels need to be monitored when lithium is taken with an ARB. 

Combining an ARB with a nonsteroidal anti-inflammatory drug (NSAID) may increase the risk of kidney problems. Kidney function may need to be monitored while taking an ARB and NSAID. 

Taking an ARB with aliskiren, ACE inhibitors, or other ARBs can increase the risk of dangerously low blood pressure (hypotension), high potassium levels (hyperkalemia), and kidney problems. 

Potassium levels in the blood should be monitored when taking an ARB with potassium-sparing diuretics, potassium supplements, or salt substitutes containing potassium. Combining an ARB with a drug or product containing potassium may increase the risk of hyperkalemia. 

This may not be a complete list of all possible drug interactions. Consult a healthcare provider with all medications you may be taking. 

Warnings of losartan and valsartan

Losartan and valsartan carry a risk of low blood pressure, or hypotension. Monitor for signs and symptoms of hypotension, including dizziness or fainting. The risk of hypotension is increased in people who take diuretics, have heart problems, or undergo dialysis. 

Losartan and valsartan may cause high potassium levels, or hyperkalemia, and changes in kidney function. Potassium levels may need to be monitored throughout treatment with an ARB like losartan or valsartan. Monitor for adverse events like weight gain and swelling in the hands or legs. 

Losartan and valsartan can cause harm to an unborn baby. These medications should not be taken during pregnancy. Consult a healthcare provider before taking an ARB while breastfeeding. 

Frequently asked questions about losartan vs. valsartan

What is losartan?

Losartan is a generic prescription drug used for the treatment of hypertension and kidney problems associated with diabetes. It can also reduce the risk of stroke in people with hypertension and left ventricular hypertrophy. Losartan is an angiotensin II receptor blocker (ARB) available as a daily oral tablet. 

What is valsartan?

Valsartan is a generic prescription drug approved to treat hypertension and heart failure. It is also approved to reduce the risk of death after a heart attack. Valsartan is an angiotensin II receptor blocker (ARB) available as an oral tablet that is taken once or twice daily. 

Are losartan and valsartan the same?

Both losartan and valsartan can lower blood pressure, which may help prevent or manage cardiovascular disease. The brand name of losartan is Cozaar while the brand name of valsartan is Diovan. They have different FDA approved uses and come in different strength tablets. 

Is losartan or valsartan better?

Losartan and valsartan are both effective antihypertensive agents. They both have generally good tolerability with mild side effects. The effectiveness of either drug may depend on certain factors, such as the dosage prescribed and the condition being treated. 

Can I use losartan or valsartan while pregnant?

Losartan and valsartan should be avoided during pregnancy. Both ARBs can cause harm to an unborn baby. 

Can I use losartan or valsartan with alcohol?

There is no direct interaction between ARBs and alcohol. In general, drinking alcohol in moderation is safe while taking an ARB. However, alcohol may worsen potential side effects of ARBs, such as dizziness.  

What is a good replacement for valsartan?

Valsartan is an ARB that can help lower blood pressure. Other examples of ARBs include Cozaar (losartan), Avapro (irbesartan), Atacand (candesartan), Benicar (olmesartan), and Micardis (telmisartan). In some cases, valsartan may be switched to a drug in a different drug class, such as ACE inhibitors, beta-blockers, alpha-blockers, calcium channel blockers, or diuretics. 

What is the safest blood pressure medication with the least side effects?

The incidence and severity of side effects can vary among blood pressure medications. Different factors, such as other medical conditions and other medications being taken, can affect how a person experiences side effects. A high daily dose of a blood pressure medication may cause more side effects than a low daily dose. A healthcare provider should be consulted on the safest blood pressure medication based on individual factors.