Losartan and Sexual Side Effects: What the Evidence Shows

Losartan (an angiotensin II receptor blocker, ARB) is generally considered neutral or even potentially beneficial for sexual function compared with some older blood pressure medications. Evidence suggests that ARBs like losartan are less likely to cause erectile dysfunction (ED) than thiazide diuretics or non‑selective beta blockers, and in some specific groups, losartan has been studied for improving ED. ^{[1] [2]} In a clinical trial of men with diabetes and ED, losartan improved erectile scores and sexual performance measures, and the combination of losartan with tadalafil was more effective than either alone. ^[3]

That said, official product information and large drug references list sexual adverse events as possible, including decreased libido (lower sex drive) and impotence/ED, though these events appear uncommon. ^{[4] [5]} Consumer-facing medication summaries also list difficulty having or keeping an erection and loss of sexual ability or desire among side effects with an unknown frequency. ^[6] These listings reflect that such events have been reported, but they do not establish that losartan commonly causes them.

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Key Takeaways

• Overall risk appears low: Sexual side effects are reported but not common in clinical trials and labeling; losartan is often favored over drugs with higher sexual side‑effect burdens. ^{[7] [1]}
• Compared with older agents: Older antihypertensives (certain beta blockers and thiazide diuretics) more clearly impair erectile function, while ARBs like losartan tend to be neutral or beneficial. ^{[1] [8]}
• Possible but uncommon events: Decreased libido and impotence are listed in losartan’s official labeling, indicating they can occur, albeit without a well‑defined frequency. ^{[4] [5]}
• Potential benefits in diabetes‑related ED: In men with diabetic ED, losartan improved erectile function, with greater benefit in mild to moderate cases. ^[3]

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What Official Sources and Trials Report

• Official medication guides and labeling for losartan (brand: Cozaar) include sexual adverse events such as “decreased libido” and “impotence” among postmarketing or infrequent reports. ^{[4] [5]} Some consumer drug references also note “trouble having or keeping an erection” and “loss in sexual ability or desire,” with incidence not specified. ^[6]
• Reviews of antihypertensive drugs indicate ARBs have little adverse effect on sexual function compared with older drugs, and may be neutral or beneficial. ^[1] Earlier surveys showed strongest evidence for sexual dysfunction with propranolol and certain older agents, with less consistent findings for others. ^[2]
• A clinical trial in diabetic men with ED found losartan improved International Index of Erectile Function (IIEF‑5) scores and increased successful penetration and intercourse completion rates; combining losartan with tadalafil further improved outcomes. ^[3]
• Large safety datasets of losartan show excellent tolerability, with common adverse events like headache or dizziness; sexual side effects are not prominent in these trial summaries. ^[7]

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Practical Perspective for Users

• If you start losartan and notice changes in libido or erections, the medication could be one of several contributors, including underlying high blood pressure, diabetes, stress, sleep issues, smoking, alcohol, or other medicines. Labeling acknowledges these effects can occur, but they are not frequent. ^{[4] [5]}
• Switching within blood pressure drug classes or adjusting therapy is often possible if sexual side effects appear; ARBs are commonly chosen to minimize sexual dysfunction compared with certain older agents. ^{[8] [1]}
• In diabetes‑related ED, losartan may help, and combining it with a PDE‑5 inhibitor like tadalafil can be more effective, under medical guidance. ^[3]

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Comparison at a Glance

Medication class	Typical effect on sexual function	Notes
ARBs (e.g., losartan)	Neutral to potentially beneficial	Sexual adverse events (decreased libido, ED) are listed but uncommon; favorable profile vs older agents. [1] [4]
Thiazide diuretics	More likely to impair erections	Older data associates with ED more than ARBs. [1] [8]
Non‑selective beta blockers (e.g., propranolol)	More likely to impair erections	Strong evidence for erectile inhibition, especially at high doses. [2]
ACE inhibitors	Generally neutral	Less associated with sexual dysfunction than older classes. [8]
Calcium channel blockers	Generally neutral	Minimal adverse effects on sexual function in reviews. [8]

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When to Seek Help

• New or worsening ED, reduced libido, or difficulty achieving orgasm: Discuss timing relative to starting losartan; your clinician can consider dose adjustments or alternative therapies. ^{[4] [5]}
• Multiple risk factors (diabetes, smoking, depression, sleep apnea): Addressing these often improves sexual function even without changing blood pressure medication. ^[1]
• Considering ED treatments: PDE‑5 inhibitors (like sildenafil/tadalafil) are effective and generally safe in hypertension, but should not be combined with nitrates and need blood pressure review. ^[1]

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Bottom Line

Losartan does not typically increase the risk of sexual side effects and is often chosen to reduce the chance of sexual dysfunction compared with some older blood pressure drugs. ^[1] While decreased libido and impotence are reported in official information, they appear uncommon, and in certain groups such as men with diabetes, losartan has shown benefits for erectile function. ^{[4] [3]} If you experience sexual changes after starting losartan, a careful review with your clinician can help determine whether the medicine, another factor, or a combination is involved, and there are practical options to improve symptoms while maintaining good blood pressure control. ^{[5] [8]}