If you are taking tadalafil to treat PAH or BPH, follow your doctor’s directions and the guidelines in this paragraph. In , the Phase 2 clinical studies were initiated for males experiencing ED, then progressed to the Phase 3 trials that supported the drug’s FDA approval. Furthermore, the longer half-life is the basis for tadalafil’s daily therapeutic use in treating pulmonary arterial hypertension. You should take tadalafil one time a day. Cialis will be available by prescription only. If you are already taking medication to treat BPH, your doctor may tell you to stop taking your other medication at least one day before starting treatment with tadalafil.AdComplete the Online Consultation with our Doctor. Personalize Your Needs. If Appropriate, Get a Prescription for ED from RexMD®. Free Shipping AvailableFree Shipping · Discreet Packaging · Real Doctors · Personalized PlanTypes: Testosterone · Finasteride · Hair Growth · Immune Support · Sertraline. Optum Store offers several ED medications with free and discreet shipping. The company sells generic tadalafil in 5, 10, and 20 mg doses. People can choose from a 30, 90, or day supply, with. Generic Cialis is called tadalafil, which is the active ingredient in Cialis. Cialis is Food and Drug Administration (FDA) approved to treat erectile dysfunction (ED) and benign .