Therefore, treatments for erectile dysfunction, including CIALIS, should not be used in men for whom sexual activity is inadvisable as a result of their underlying cardiovascular status. In those patients already taking an optimized dose of PDE5 inhibitor, alpha-blocker therapy should be initiated at the lowest dose. The drug is approved for use in adults. The dose of CIALIS for use as needed should be limited to 10 mg no more than once every 72 hours in patients taking potent inhibitors of CYP3A4 such as ritonavir, ketoconazole, and itraconazole [see Drug Interactions 7. In those patients who are stable on alpha-blocker therapy, PDE5 inhibitors should be initiated at the lowest recommended dose.Cialis prices mg Cialis oral tablet from $ for 30 tablets 5 mg Cialis oral tablet from $ for 30 tablets 10 mg Cialis oral tablet from $2, for 30 tablets Cialis oral . Tadalafil (Cialis) is taken by mouth either as needed before sexual activity or once daily for erectile dysfunction (ED).It’s also taken once daily to treat symptoms from an enlarged prostate (benign prostatic hyperplasia, or BPH).Tadalafil (Cialis) is available both as brand-name and generic tablets. Common side effects of this medication include . Health Information Center. New Prescriptions. Refill Prescriptions. Transfer Rx to CVS. View/Print Prescription History. Rapid Refill. New York Patient Bill of Rights. NY .