Grapefruit juice is a weak inhibitor of CYP3A4 gut wall metabolism and may give rise to modest increases in plasma levels of sildenafil. In another clinical pharmacology study, tadalafil 20mg was studied in combination with up to 4 classes of anti-hypertensives. This medication may also be used for other conditions. Cialis can be taken with or without food. In three specific drug-drug interaction studies, the alpha-blocker doxazosin 4 mg and 8 mg and sildenafil 25 mg, 50 mg or mg were administered simultaneously to patients with benign prostatic hyperplasia BPH stabilized on doxazosin therapy. Prior to initiating treatment with tadalafil for BPH, patients should be examined to rule out the presence of carcinoma of the prostate and carefully assessed for cardiovascular conditions see section 4. European urology, 63 5 , Tadalafil is used to treat erectile dysfunction, a condition where you are unable to get or keep an erection firm enough to have sexual intercourse. It works by . Tadalafil is the generic name of a drug. Cialis® is the brand name owned by the company Eli Lilly. It is a phosphodiesterase type 5 (PDE5) inhibitor used for erectile dysfunction . 7 pm to 10 pm. Saturday & Sunday: 7 pm to 10 pm. Public Holidays: Closed. Cialis® is the brand name of a drug owned by the company Eli Lilly. Tadalafil is the generic name. It .