If Fildena CT 100 mg contains sildenafil 100 mg, taking it after a heavy meal—especially a high-fat meal—is generally not dangerous by itself, but it can make the medicine start working later. Sildenafil can be taken with or without food. A high-fat meal can delay the peak blood level by about 1 hour and reduce the peak concentration by about 29%. D DailyMed +1 So instead of feeling an effect around 30–60 minutes, you may need to wait longer. Don't take an extra tablet because it seems slow to work. The food doesn't necessarily eliminate the effect; it mainly slows absorption. P PubMed Since 100 mg is the usual maximum recommended sildenafil dose for ED in 24 hours, don't take another sildenafil-containing product (Cenforce, Malegra, Fildena, etc.) the same day. D DailyMed If you've already taken Fildena CT 100 after a heavy meal, tell me roughly what time you took it and what you ate, and I can estimate when you might expect it to take effect.