If you miss a dose of Fildena CT 100, you should take it as soon as you remember, but only if you plan to engage in sexual activity. Fildena CT 100, containing sildenafil citrate, is not meant for daily use unless prescribed that way. It is usually taken as needed, about 30 to 60 minutes before sexual activity. If it's almost time for your next planned dose or if you don't intend to have sexual activity, skip the missed dose and do not double up to make up for it. Taking more than the prescribed amount can increase the risk of serious side effects, including dizziness, vision changes, or prolonged erections. Always follow your doctor’s instructions.