Can I take Sildenafil and Losartan together?

Why this happens

Both medications work by widening your blood vessels to lower blood pressure. When used together, their effects can add up, causing a more significant drop in blood pressure than either drug would cause on its own.

What you should do

Use caution when combining these medications. If you feel dizzy or lightheaded, sit or lie down until the feeling passes. It is best to avoid rising quickly from a sitting or lying position. If you experience severe dizziness or fainting, contact your doctor.

Important precautions

Pregnancy

You must not take losartan if you are pregnant or planning to become pregnant, as it can cause serious harm or death to an unborn baby, particularly in the second and third trimesters.

Nitrate medication use

Never take sildenafil if you are also using nitrate medicines (such as glyceryl trinitrate or isosorbide mononitrate) for chest pain or heart problems. Combining them can cause a sudden, life-threatening drop in blood pressure.

High potassium levels (Hyperkalaemia)

Losartan can increase potassium levels in your blood. Avoid using potassium supplements or salt substitutes containing potassium unless specifically advised by your doctor.

Food and drink warnings

Alcohol

Drinking alcohol while taking losartan can increase the blood pressure-lowering effect of the medicine. This may make you feel dizzy, lightheaded, or faint, especially when standing up. It is best to keep your alcohol intake within recommended limits and see how the medicine affects you before drinking.

Potassium-rich foods and salt substitutes

Losartan can increase the levels of potassium in your blood. You should avoid using salt substitutes that contain potassium (often labelled as 'low sodium' salts) and speak to your doctor before significantly increasing your intake of high-potassium foods like bananas, spinach, or sweet potatoes. High potassium levels can affect your heart rhythm.

Grapefruit juice

Grapefruit juice can increase the amount of sildenafil in your bloodstream, which may increase the risk of side effects. It is generally advised to avoid drinking large amounts of grapefruit juice when using this medication.

High-fat meals

If you take sildenafil with a heavy or high-fat meal (such as a burger and chips), the medicine may take longer to start working. For the fastest effect, it is best taken on an empty stomach or with a light meal.

Using other medicines

Taking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.

Disclaimer

This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.