Duac generic equivalent it is taken by mouth with a glass of water approximately 0,5-1 hour before sexual activity. Fildena should not be taken more than once a day. Super P-Force cannot be used in patients with allergy to the medication and its components and also in individuals treated with nitrates (such as nitroglycerin). This combination can cause very low blood pressure potentially dangerous to result in a stroke, heart attack, or death. Do not take this medication if you are under 18 y.o.