Viagra is intended to be taken as needed before ... brand-name Cialis is available in only 5-mg doses. At this dose, Cialis can be taken either on an “as-needed” basis or on a daily basis.

Each medication has its own dosage meter. Viagra doses are 25 milligrams (mg), 50 mg, and 100 mg. Cialis and tadalafil doses are 5 mg, 10 mg, and 20 mg. Cialis also has a lower dose of 2.5 mg that ...