Tadalafil: new preparation. Slightly more convenient, but poorly assessed in organic disorders

(1) The standard oral treatment for erectile dysfunction is sildenafil, a type 5 phosphodiesterase inhibitor, whether the underlying problem is organic (for example, post prostatectomy or spinal cord damage) or psychological. (2) Another inhibitor of the same type, tadalafil, has been available in France since early 2003. (3) At 10 mg to 20 mg, tadalafil is more effective than placebo, including in diabetic patients. But placebo-controlled trials have included few patients with a history of total prostatectomy, spinal cord damage, or sildenafil failure. One trial, which was not published in detail, reported that the effects last more than 12 hours. But the European Medicines Evaluation Agency considered that the reported data did not support this conclusion. There was no significant difference between active treatment and placebo groups after 12 hours. The risk-benefit ratio of long term treatment with tadalafil is unknown. (4) The two available comparative trials do not rule out the possibility that tadalafil is less effective than sildenafil. (5) Known adverse effects and drug interactions are similar in both tadalafil and sildenafil. Both drugs are contraindicated in patients using nitrate derivatives, because of a risk of abrupt hypotension. (6) Unlike sildenafil, administration of tadalafil does not retard its action. (7) In practice, sildenafil remains the first line option for treating erectile dysfunction with an organic cause. Tadalafil is slightly easier to use.