If you are taking tadalafil to treat erectile dysfunction, you should know that it does not cure erectile dysfunction or increase sexual desire. Will Cialis be prescription or OTC over-the-counter? You can report an adverse event either online, by regular mail or by fax, using the contact information at the bottom of this page. Do not take more or less of it or take it more often than prescribed by your doctor. The safety and effectiveness of Cialis when used with other treatments for impotence has not been studied.The drug comes in low-dose versions that can be taken daily. This means you can have sex at any time, rather than needing to take a pill from time to time as needed like other ED brands. The starting dose for daily-use Cialis is milligrams (mg). If that doesn’t work, you can increase your daily dose up to 5 mg. Do not break or split a Cialis tablet. Swallow it whole. For erectile dysfunction, take Cialis just before sexual activity but not more than once per day. It can be used up to 36 hours before sexual activity. Cialis can help achieve an erection when sexual stimulation occurs. An erection will not occur just by taking a pill. 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.