Botulinum Toxin A (Botox) for Relieving Penile Retraction

ABSTRACT Introduction The flaccid penis undergoes retraction upon contraction of the dartos muscle. These contractions are most pronounced in the situations of cold, stress, and upon exercising, and can be the source of embarrassment to those who have a hyperactive retraction reflex, especially when exposed to their partners or to others in showers and dressing rooms, despite a normal and satisfactory length in the erect state. Aim In this work, we propose an alternative to surgery and penile extenders for alleviating penile retraction, by injection of botulinum toxin into the dartos to induce muscle relaxation. This is the first report of the technique. Methods Ten male patients complaining of a short penis exclusively in the flaccid state, despite normal and satisfactory erect and outstretched lengths, were selected for the study. One hundred units of BOTOX were injected into the dartos muscle. Main Outcome Measures Frequency and amplitude of penile retraction, flaccid unstretched length, and patient satisfaction. Results Seven out of 10 cases (70%) subjectively reported a decrease in the frequency and amplitude of penile retraction, as well as improvement in flaccid length. Clinical measurements were less pronounced but still showed an improvement that was mainly in terms of less retraction rather than more length. No side effects were reported. Improvement faded completely by the 6th month. Conclusion This preliminary report of botulinum toxin A (Botox) injection into the dartos muscle shows that Botox may have a potential effect in temporarily decreasing penile retractions in terms of frequency and amplitude.