Cialis should not be used by patients taking nitrates such as nitroglycerin tablets or patches because the combination of these with Cialis could significantly lower blood pressure and lead to fainting or even death in some men. We will ask about your experience with generic Cialis as part of your visit. One advantage Cialis has over Viagra and Levitra is its What special dietary instructions should I follow? What if I am taking other drugs? Tadalafil may not be safe for people with certain medical conditions, including people who have had a stroke , have coronary heart disease or retinitis pigmentosa an eye disease.Cialis (tadalafil): This ED medication works with the same principle as Viagra, but lasts up to 36 hours. It’s available in mg, 5 mg, 10 mg, and 20 mg tablets. . milligrams (mg) 5 mg 10 mg 20 mg The cost for these different strengths depends on whether you have insurance, your individual plan coverage, and your . tadalafil. erectile dysfunction (ED) benign prostatic hyperplasia, or BPH). Tadalafil (Cialis) is available both as brand-name and generic tablets. Common side .