Erectile dysfunction is a condition where the penis does not harden and expand when a man is sexually excited, or when he cannot keep an erection. It’s best to check your chosen provider’s site for more information. Tadalafil works on the PDE5 enzyme in the lungs to relax the blood vessels. Without physical action to the penis, such as that occurring during sexual intercourse, tadalafil will not work to cause an erection. More serious side effects may include a drop in blood pressure or an erection that lasts longer than four hours. Tadalafil will make these symptoms less severe and reduce the chance that prostate surgery will be needed. You can see an in-person provider or speak with a doctor virtually.Drug details Here are some details about Cialis: Drug form: oral tablet Generic version: tadalafil Read on to learn about Cialis and cost, as well as how to save money on prescriptions and find. stockcam / Getty Images What is generic Cialis? Generic Cialis is called tadalafil, which is the active ingredient in Cialis. Cialis is Food and Drug Administration (FDA) approved to treat. Cialis Prices, Coupons and Patient Assistance Programs. Cialis (tadalafil) is a member of the impotence agents drug class and is commonly used for Benign Prostatic Hyperplasia, and Erectile Dysfunction. The cost for Cialis oral tablet mg is around $ for a supply of 30 tablets, depending on the pharmacy you visit.