Your doctor will probably tell you not to take tadalafil if you are taking street drugs containing nitrates. Read more on male sexual health on the Sexual Health Australia site. Cialis will be available by prescription only. How can I buy tadalafil? If you have an erection that lasts for more than 4 hours, you should go to the nearest hospital emergency department. Communicate with your partner and interact with them after you take Cialis to help the medication work.The most commonly reported side effects in patients treated with Cialis during the testing of the product were: headache. indigestion. back pain. muscle pain. flushing. stuffy nose. Patients who. Roman is a telehealth prescription service and online pharmacy that provides prescription Cialis for ED and a host of other conditions, like hair loss, cold sores, and premature ejaculation. When. Tadalafil (Cialis) is used to treat erectile dysfunction (ED, impotence; inability to get or keep an erection), and the symptoms of benign prostatic hyperplasia (BPH; an enlarged prostate) which include difficulty urinating (hesitation, dribbling, weak stream, and incomplete bladder emptying), painful urination, and urinary frequency and urgency in adult men.