If you are thinking about using tadalafil please discuss it with your doctor. Payment options: Consider how you’d like to pay. They have the same benefits and risks as their brand-name counterparts. The most common symptoms of erectile dysfunction include difficulty achieving or maintaining an erection and reduced sexual desire. All PDE5 inhibitors, including Viagra and Cialis, require a valid prescription regardless of the pharmacy or provider. Both options require valid medical documentation, but some online services only require a health questionnaire to be filled out and reviewed for approval—meaning no face-to-face video interaction is needed.Cialis (tadalafil): This ED medication works with the same principle as Viagra, but lasts up to 36 hours. It’s available in mg, 5 mg, 10 mg, and 20 mg tablets. . About tadalafil Brand names: Cialis, Adcirca. About tadalafil. Tadalafil is a medicine used to treat erection problems (erectile dysfunction) and symptoms of an enlarged prostate (benign prostate enlargement). It’s also sometimes used to treat pulmonary hypertension (high blood pressure in the blood vessels that supply the lungs). Cialis comes in several strengths: milligrams (mg), 5mg, 10 mg, and 20 mg. The Cialis cost per pill and daily cost depend on several factors, such as: the strength prescribed by your doctor;.