Giuliano F et al. (2007) Efficacy and safety of tadalafil in men with erectile dysfunction following spinal cord injury. Arch Neurol [doi:10.1001/archneur.64.11.nct70001]

Erectile dysfunction (ED) is a common complication of spinal cord injury (SCI), which occurs most frequently in young men. The severity of sexual problems experienced depends on the neurological lesion, but only a quarter of men with SCI have erections that enable them to have intercourse. This has serious consequences for their quality of life.

Tadalafil, a potent oral phosphodiesterase-5 inhibitor, is known to be effective and well tolerated in men with ED unrelated to SCI. Following sexual stimulation, tadalafil facilitates an erection through the action of the second messenger cyclic guanosine monophosphate in smooth muscle cells. Giuliano et al. have investigated whether tadalafil can also improve sexual function in men with SCI.

To determine the safety and efficacy of tadalafil, they performed a multicenter, randomized, double-blind, placebo-controlled study in patients with ED secondary to SCI. All men had sustained their injury at least 6 months before the trial began. Following a 4-week assessment period, 142 patients were given tadalafil and 44 patients were given placebo for a 12-week, on-demand treatment period.

Erectile function improved significantly in the men taking tadalafil compared with controls. Penetration attempts and intercourse attempts were both more successful and the treatment group experienced a higher percentage of improved erections and ejaculatory frequency than the control group. Only mild adverse effects, such as headache, were noted. The authors conclude that tadalafil improves erectile function and is well tolerated by men with ED secondary to traumatic SCI.