The importance of an early pharmacological prophylaxis for erectile function following nerve-sparing radical prostatectomy has been recently stressed by several authors. In spite of that, patient's compliance to erectile rehabilitation protocols seems to be low. The present review is an attempt to define the expected benefits of the currently proposed rehabilitative protocols in terms of cost-efficiency and quality of life. The conclusion is that current scientific evidence in support of an early postoperative use of erectile aids is based mainly on indirect proof of a cavernosal damage that may follow the temporary postoperative 'erectile silence'. Intracavernosal injections or a vacuum device may represent the best first-line treatment option for the first few months from the procedure as their mechanism of action does not require intact neural tissue for erection. Thereafter oral phosphodiesterase 5 inhibitor therapy may be a reasonable choice for those patients who can achieve at least a partial erection. A phosphodiesterase 5 inhibitor may not be effective when spontaneous erections are absent. It is possible, since the rehabilitation of sexual function aims to prevent cavernosal tissue damage by providing oxygenation to the erectile tissue, the choice of a potentially ineffective treatment may jeopardize the results of a reasonable nerve-sparing procedure.