Fildena CT 100 can affect your heart and blood pressure, so it is important to understand the risks before taking it. Fildena CT 100 is commonly marketed as a 100 mg chewable tablet containing sildenafil, the same active ingredient used in Viagra. Sildenafil relaxes blood vessels, which helps increase blood flow to the ***** but can also lower blood pressure throughout the body. How it can affect your heart Blood pressure may drop: You may experience dizziness, light-headedness, or fainting. Heart rate may change: Some people experience palpitations or a noticeable heartbeat. Existing heart disease matters: ***** activity and sildenafil may be unsafe for some people with unstable heart conditions. Certain medicines are dangerous together: Combining sildenafil with nitrate medicines such as nitroglycerin or isosorbide can cause a potentially life-threatening drop in blood pressure. Riociguat is also contraindicated. For many people with stable cardiovascular health, sildenafil can be used safely when appropriately prescribed. However, 100 mg is the maximum usual recommended single dose, not necessarily the safest starting dose. When to seek medical help Get emergency medical help if you develop chest pain, severe shortness of breath, fainting, or a fast or irregular heartbeat. If chest pain occurs after taking sildenafil, do not take nitroglycerin yourself; tell emergency responders when you took sildenafil. NHS +1