Learn about the potential side effects of tadalafil. Includes common and rare side effects information for consumers and healthcare. Tadalafil (Cialis) is one of the most popular erectile dysfunction (ED) drugs Taking a daily low-dose pill may reduce side effects, though it may. Evaluation of the long-term safety and effectiveness of tadalafil once . All tests of treatment effects were conducted with a two-sided alpha. Table 1: Tadalafi, characteristics Click here to view. Most patients that experienced side effects such as myocardial infarction, sudden cardiac death, stroke, palpitationsand tachycardia had preexisting cardiovascular risk factors. Learn more here to:. Although not all of these side effects may occur, if they do occur they may need medical attention. You are encouraged to report negative side effects of prescription drugs to the FDA. Click here to view. Only your healthcare provider and you can decide if Cialis is right for you. First Name Optional. Many of these events were reported to occur during or shortly after sexual activity. At week 4, significantly greater percentages of men being treated with Cialis 2.