Levitra vardenafil : This medication is taken one hour before sex and can last up to 24 hours. 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. Erectile dysfunction medications require a prescription from a licensed provider. You take one 2. You can see an in-person provider or speak with a doctor virtually. Some platforms have a digital pharmacy that ships the medication to your home, while others send an electronic prescription to your local pharmacy. Some services offer a subscription option where they’ll send your medications every month at a discount.All US based pharmacies must follow FDA regulations to ensure safe and high quality medicine. A large proportion of the Cialis available online is counterfeit, so it’s important to get your Cialis from a reputable pharmacy you trust that is based in the US.  · But on average, its effects start to lessen 2 to 3 hours after you take a dose. The typical dose for once-daily Cialis for ED is milligrams (mg) to 5 mg. When used as needed for ED, the usual. Cialis and generic tadalafil are available in four different strengths— mg, 5 mg, 10 mg and 20 mg—but which one should you take? If you’ve never tried Cialis before, your doctor will likely start you on a low dose, like mg or 5 mg. The 20 mg tablet is the highest strength and is often not preferred because it has the potential to.