Complete Guide to Sildenafil Side Effects
Common Side Effects of Sildenafil
The most frequently reported side effects of sildenafil affect up to 1 in 10 men taking the medication. These typically include headaches, flushing (redness of face and neck), indigestion, and nasal congestion. According to BNF guidance, these effects are usually mild to moderate and tend to diminish as your body adjusts to the treatment over several doses.
Headaches are the most common side effect, affecting approximately 16% of men in clinical trials. This occurs because sildenafil can cause blood vessel dilation throughout the body, not just in the genital area. Taking the medication with plenty of water and avoiding alcohol may help reduce this effect.
Visual and Hearing Side Effects
Some men may experience temporary visual disturbances, including mild and temporary changes in colour vision (particularly blue-green discrimination), increased sensitivity to light, or blurred vision. These effects are typically mild and resolve within a few hours. However, if you experience sudden vision loss in one or both eyes, discontinue use immediately and seek urgent medical attention.
Rare hearing-related side effects may include sudden decrease or loss of hearing, sometimes accompanied by ringing in the ears (tinnitus) or dizziness. While uncommon, these symptoms require immediate medical evaluation as they may indicate a serious adverse reaction.
Cardiovascular Considerations
Sildenafil can cause temporary decreases in blood pressure, which may result in dizziness, particularly when standing up quickly. This effect is more pronounced in men already taking blood pressure medications or those with existing cardiovascular conditions. The BNF emphasises careful monitoring for men with heart conditions, as the combination of sildenafil with sexual activity may place additional strain on the cardiovascular system.
Chest pain during or after sexual activity while taking sildenafil requires immediate medical attention, as this may indicate a serious cardiovascular event. Never take nitrate medications (such as GTN spray) if you've used sildenafil within the past 24 hours, as this combination can cause dangerous drops in blood pressure.
Serious Side Effects Requiring Immediate Medical Attention
Priapism, a prolonged erection lasting more than 4 hours, is a rare but serious side effect requiring emergency treatment. This condition can cause permanent damage to penile tissue if not treated promptly. While affecting less than 1% of users, it represents a medical emergency.
Severe allergic reactions to sildenafil are extremely rare but can include difficulty breathing, swelling of face, lips, tongue or throat, and severe skin reactions. Any signs of allergic reaction require immediate discontinuation and emergency medical care.
Minimising Side Effects
Starting with the lowest effective dose (typically 25mg or 50mg) and adjusting based on response and tolerability helps minimise side effects. Taking sildenafil on an empty stomach or with a light meal reduces the likelihood of indigestion, while avoiding alcohol can decrease the risk of headaches and dizziness.
Both Viagra (branded) and sildenafil (generic) contain identical active ingredients with the same side effect profiles. At EverydayMeds, our clinical team provides personalised dosing recommendations following comprehensive health assessments to optimise effectiveness while minimising adverse effects. Regular monitoring ensures ongoing safety and treatment success.
