Ask your pharmacist for a list of the ingredients. It may be taken with or without food. Soon, in , ICOS received a patent for compound IC structurally unlike sildenafil and vardenafil , and Phase 1 clinical trials began in Avoid eating a large meal or a lot of food, as this can slow down the effects of the drug. How will Cialis be supplied? This medicine is available only with your doctor’s prescription.Tadalafil (Cialis) is a medicine used to treat erectile dysfunction (ED, also called impotence) and problems with urination caused by an enlarged prostate (benign prostatic hypertrophy or BPH). Tadalafil works by helping to relax the blood vessels in the penis, allowing blood to flow into the penis, and causing an erection. Cialis is taken as an oral tablet, either as a low dose daily medication or as a higher-dose “on-demand” medication. It is the brand name for tadalafil, a medication also . In combination with sexual stimulation, tadalafil works by increasing blood flow to the penis to help a man get and keep an test1.rufil is also used to treat the symptoms of an .