Medicines used for erectile dysfunction (ED) can be effective, but they are not suitable for everyone. Before using any ED treatment, it is important to understand what the medicine contains, how it should be taken and whether it could interact with your health conditions or other medicines.

This guide provides general information to help you make informed decisions. It should not replace the patient information leaflet supplied with a medicine or advice from a doctor or pharmacist.

Understanding ED Medicines

Several medicines are used to treat erectile dysfunction. Sildenafil is one of the best known and belongs to a group of medicines called PDE5 inhibitors. It works by supporting increased blood flow to the penis when a man is sexually stimulated.

ED medicines do not automatically cause an erection and sexual stimulation is still required. Different treatments can also vary in strength, how quickly they work and how long their effects may last.

Always check the active ingredient and strength rather than relying only on a brand or product name.

Before Taking ED Medication

ED treatment is not appropriate for every person. Speak to a doctor or pharmacist if you are unsure whether a medicine is suitable, particularly if you have heart problems, very low or uncontrolled high blood pressure, liver or kidney problems, or have previously experienced a serious reaction to an ED medicine.

You should also tell a healthcare professional about other medicines, supplements or herbal products you take.

Sildenafil must not be taken with nitrate medicines commonly used for chest pain. Combining the two can cause a dangerous fall in blood pressure. Sildenafil can also interact with some other medicines, including certain treatments for high blood pressure, HIV, fungal infections and other conditions.

Taking Your Medicine Safely

Follow the instructions provided with your particular medicine. Do not assume that instructions for one ED treatment apply to another.

For sildenafil used for erectile dysfunction, it is commonly taken before sexual activity. The correct dose and timing depend on the product and individual circumstances. Never take more than the recommended amount in an attempt to make the treatment work faster or produce a stronger effect.

Heavy alcohol consumption may make it more difficult to achieve an erection and can increase unwanted effects such as dizziness.

Possible Side Effects

Like all medicines, ED treatments can cause side effects. With sildenafil, commonly reported effects include headache, facial flushing, indigestion, dizziness, a blocked nose and temporary changes in vision.

Most side effects are not serious, but you should seek medical advice if symptoms are persistent or concerning.

Urgent medical attention is needed for serious reactions. These can include severe chest pain, a seizure, a serious allergic reaction or a painful erection lasting more than four hours. Sudden changes or loss of vision also require prompt medical assessment.

Accessing Medicines Online

Take care when obtaining any medicine online. A professional-looking website alone does not show that a seller is properly regulated or that a medicine is genuine.

UK guidance recommends checking that an online pharmacy is appropriately registered. In Great Britain, pharmacy registration can be checked through the General Pharmaceutical Council (GPhC). Unregulated websites may supply medicines that are falsified, incorrectly dosed, unsuitable or unauthorised.

You should be particularly cautious of websites offering prescription-only medicines without an appropriate prescription or health assessment.

Keep the Patient Leaflet

Read the patient information leaflet before taking any medicine and keep it in case you need to check something later. The leaflet contains product-specific information about dosage, interactions, side effects and situations in which the medicine should not be used.

If you are uncertain about a medicine, have an existing medical condition or take other medication, speak to a pharmacist or doctor before using it.