In some cases, ED can cause a strain on relationships and impact self-esteem. All PDE5 inhibitors, including Viagra and Cialis, require a valid prescription regardless of the pharmacy or provider. Your primary care doctor should always know what medications you’re taking, including ED pills prescribed by another provider. Tadalafil is approved by the FDA to treat erectile dysfunction. Your primary care doctor should always know what medications you’re taking, including ED pills prescribed by another provider. Cialis Daily tadalafil : This low-dose Cialis works by increasing blood flow to the penis over time, making it easier to have an erection when aroused.tadalafil or cialis Savings, Coupons and Information. | TADALAFIL (tah DA la fil) treats erectile dysfunction (ED). It works by increasing blood flow to the penis, which helps to maintain an erection. Cialis is approved by the FDA to treat erectile dysfunction (ED). Our medical team can prescribe Cialis 5mg, 10mg, and 20mg. The starting dose we generally recommend is 10mg. Tadalafil is the name for the active chemical ingredient in Cialis. Used for Benign Prostatic Hyperplasia, Erectile Dysfunction. erectile dysfunction (ED) benign prostatic hyperplasia, or BPH). Tadalafil (Cialis) is available both as brand-name and generic tablets. Common side effects of this medication include headache and indigestion. Tadalafil (Cialis) does interact with some medications.