Male erectile dysfunction is treated with tadalafil CT 20. It helps men achieve an erection by increasing blood flow to the penis. You can take Tadalafil CT 20 with food or without any food. It must be taken exactly as prescribed by your physician. You must be sexually excited for the medication to assist you in achieving an erection. About an hour before you intend to have sex, you should take it. Individual differences in productivity mean that working takes anywhere from half an hour to an hour. You can take Tadalafil CT 20 with food or without any food. It must be taken exactly as prescribed by your physician.