Furosemide is a loop diuretic commonly prescribed in the UK for managing fluid retention associated with heart failure, kidney disease, and liver cirrhosis. Whilst effective at reducing oedema and blood pressure, some men taking furosemide report concerns about erectile dysfunction. Understanding whether furosemide causes erectile dysfunction—and how to manage sexual side effects whilst continuing essential treatment—is important for maintaining both cardiovascular health and quality of life. This article explores the evidence linking furosemide to erectile dysfunction, the mechanisms involved, and practical management strategies aligned with NHS and NICE guidance.

What Is Furosemide and How Does It Work?

Furosemide is a loop diuretic listed in the British National Formulary (BNF) and widely used in UK primary and secondary care. It is primarily prescribed for managing fluid retention (oedema) associated with conditions such as congestive heart failure, chronic kidney disease, liver cirrhosis with ascites, and pulmonary oedema. Furosemide may also be used for hypertension in selected situations—for example, in people with chronic kidney disease or resistant hypertension—but it is not a first-line treatment for essential high blood pressure (NICE NG136).

The medication works by acting on the loop of Henle in the kidneys, specifically blocking the sodium-potassium-chloride cotransporter. This action prevents the reabsorption of sodium and chloride, leading to increased urine production and subsequent reduction in fluid volume within the body. By promoting diuresis, furosemide effectively reduces the workload on the heart and lowers blood pressure. It typically begins working within one hour of oral administration, with effects lasting approximately six hours, making it especially useful in acute settings where prompt fluid removal is clinically necessary.

Furosemide is available in various formulations, including tablets (20 mg, 40 mg, and 500 mg) and oral solution, as well as intravenous preparations for hospital use. The 500 mg tablet strength is reserved for specialist use in severe renal impairment. The MHRA (Medicines and Healthcare products Regulatory Agency) monitors its safety profile, and prescribers must consider individual patient factors when determining appropriate dosing.

Common side effects include electrolyte imbalances (particularly hypokalaemia, hyponatraemia, and hypomagnesaemia), dehydration, postural hypotension, and increased urination frequency. Other important adverse effects include ototoxicity (hearing loss or tinnitus, especially with rapid intravenous use, high doses, or when combined with aminoglycoside antibiotics), hyperuricaemia (which may precipitate gout), and photosensitivity. If you experience any hearing changes, seek medical advice promptly.

Regular monitoring of renal function and electrolytes (urea and electrolytes, U&Es) is recommended at baseline, after initiation or dose adjustments, and during intercurrent illness, in accordance with NICE guidance on chronic heart failure (NG106) and hypertension management (NG136). Monitoring frequency should be individualised, particularly in elderly patients, those with chronic kidney disease, or those on combination diuretic therapy. If you experience any suspected side effects, you can report them via the MHRA Yellow Card Scheme at yellowcard.mhra.gov.uk or through the Yellow Card app.

Why Diuretics May Affect Sexual Function

The relationship between diuretics and erectile dysfunction (ED) is recognised in clinical practice, though robust evidence linking loop diuretics such as furosemide to ED is limited. Associations between diuretics and sexual dysfunction are better described for thiazide-type diuretics. It is important to note that multiple factors often coexist in patients requiring these medications, and the underlying cardiovascular or renal condition itself frequently contributes more substantially to erectile dysfunction than the medication.

Several mechanisms have been proposed, though these remain largely theoretical for furosemide:

• Reduced blood flow: Diuretics lower overall blood volume and can reduce blood pressure. Since achieving and maintaining an erection requires adequate arterial blood flow to the penile tissues, reductions in vascular perfusion may theoretically impair erectile function, though direct evidence for this mechanism with loop diuretics is lacking.

• Electrolyte disturbances: Furosemide can cause hypokalaemia and hypomagnesaemia, which may affect smooth muscle function and nerve conduction. These electrolyte imbalances could theoretically impact the neurovascular mechanisms essential for normal erectile function.

• Hormonal effects: Some research suggests that certain diuretics may influence testosterone levels or zinc metabolism, though evidence specific to furosemide remains very limited and requires further study.

• Psychological factors: The underlying conditions requiring furosemide—such as heart failure or hypertension—often carry psychological burdens including anxiety and depression, which are themselves significant risk factors for erectile dysfunction.

It is also important to recognise that other medications commonly prescribed alongside furosemide may contribute to erectile dysfunction, including beta-blockers, some antidepressants (SSRIs/SNRIs), and 5-alpha-reductase inhibitors. Endothelial dysfunction, atherosclerosis, and reduced cardiovascular fitness associated with chronic disease are well-established causes of ED. Therefore, whilst furosemide may be a contributory factor, erectile dysfunction in people taking this medication is usually multifactorial.

Managing Erectile Dysfunction While Taking Furosemide

If you are experiencing erectile dysfunction whilst taking furosemide, several management strategies may be appropriate, always in consultation with your healthcare team. Do not stop or adjust your furosemide dose without medical advice, as this medication is often essential for managing serious underlying conditions such as heart failure, kidney disease, or liver cirrhosis.

Medication review: Your GP may consider whether your overall medication regimen can be optimised. Switching from a loop diuretic to another class (such as a thiazide or potassium-sparing agent) is only appropriate in selected situations—for example, if furosemide was prescribed for hypertension without oedema—and must be done under close medical supervision. In people with heart failure, chronic kidney disease, or liver cirrhosis requiring oedema control, changing from a loop diuretic may risk clinical decompensation and is rarely appropriate. Any changes must be carefully monitored with blood tests to assess renal function and electrolyte balance.

Electrolyte optimisation: Ensuring adequate potassium and magnesium levels may help. Your GP can arrange blood tests to check for deficiencies. Foods rich in potassium include bananas, oranges, spinach, and potatoes. However, if you have chronic kidney disease or are taking ACE inhibitors, angiotensin receptor blockers (ARBs), or spironolactone, do not increase dietary potassium without medical advice, as this may cause dangerously high potassium levels (hyperkalaemia). Dietary advice should be individualised based on your blood test results and renal function.

Phosphodiesterase-5 (PDE5) inhibitors: Medications such as sildenafil (Viagra), tadalafil (Cialis), or vardenafil may be prescribed for erectile dysfunction. These are generally safe to use alongside furosemide, though your doctor will assess for contraindications and cautions:

• Contraindicated with nitrates (e.g., GTN spray or tablets for angina) or riociguat (for pulmonary hypertension)

• Caution required with alpha-blockers (e.g., doxazosin, tamsulosin) due to risk of low blood pressure

• Dose adjustments may be needed if you have significant kidney or liver impairment (check BNF)

Generic sildenafil is generally available on NHS prescription; some PDE5 formulations or dosing regimens may be subject to Selected List Scheme (SLS) restrictions—your GP can advise on NHS prescribing options. NICE guidance (CKS: Erectile dysfunction) supports the use of PDE5 inhibitors as first-line treatment for ED.

If you are prescribed a PDE5 inhibitor, seek urgent medical care if you develop an erection lasting more than four hours (priapism) or sudden visual or hearing loss.

Non-pharmacological options: Vacuum erection devices and psychosexual therapy or counselling may be helpful, particularly where psychological factors are prominent. Your GP can discuss these options and arrange referral if appropriate.

Lifestyle modifications: Addressing modifiable risk factors can significantly improve erectile function:

• Maintaining a healthy weight

• Regular physical activity (as appropriate for your cardiac status)

• Smoking cessation

• Limiting alcohol consumption

• Managing stress and mental health

Cardiovascular optimisation: Improving the management of your underlying heart or kidney condition may indirectly benefit sexual function by improving overall cardiovascular fitness and wellbeing. Cardiac rehabilitation programmes, where appropriate, can be particularly beneficial.

When to Speak to Your GP About Sexual Side Effects

Sexual health is an important aspect of overall wellbeing, and discussing erectile dysfunction with your GP is both appropriate and encouraged. Many men feel embarrassed about raising these concerns, but healthcare professionals routinely address such issues and can offer effective support.

Seek emergency care (call 999 or attend A&E) if you experience:

• Chest pain, particularly if severe, crushing, or radiating to the arm, neck, or jaw

• Acute severe breathlessness or symptoms suggestive of acute coronary syndrome

You should arrange an appointment with your GP if:

• You develop new or worsening erectile dysfunction after starting furosemide or increasing the dose

• Sexual difficulties are affecting your quality of life or relationships

• You are considering stopping your medication due to sexual side effects (your GP can explore safer alternatives)

• You experience erectile dysfunction alongside other concerning symptoms such as leg swelling or reduced exercise tolerance

• You have persistent difficulties despite trying lifestyle modifications

During your consultation, your GP will likely:

• Take a comprehensive history, including the onset and severity of symptoms

• Review all your current medications, as multiple drugs can contribute to ED

• Assess cardiovascular risk factors and overall disease control

• Arrange blood tests to check testosterone levels (measured in the early morning and repeated if low), HbA1c (to exclude diabetes), lipid profile, thyroid function (TSH), and renal function with electrolytes (U&Es)

• Examine blood pressure control and consider whether adjustments to your treatment regimen are appropriate

Your GP may refer you to specialist services if:

• There is diagnostic uncertainty requiring further investigation

• First-line treatments are ineffective or contraindicated

• Underlying cardiovascular disease requires specialist input

• Psychological factors are prominent and would benefit from specialist psychosexual counselling

Remember: Erectile dysfunction can be an early warning sign of cardiovascular disease, so discussing these symptoms may have broader health benefits beyond sexual function. The NHS provides access to various treatment options, and addressing the issue promptly can significantly improve your quality of life whilst ensuring your essential medications like furosemide continue to protect your heart and kidneys effectively.

Frequently Asked Questions