The effect of local anesthetic on the hypersensitive and nonsensitive areas of the penis is different in primary premature ejaculation: a pilot study

Abstract Background Penile hypersensitivity is not the whole penis, but rather only a part of the penis. Though local anesthetic can prolong intravaginal ejaculation latency time by reducing penile hypersensitivity, the effect on the hypersensitive and nonsensitive areas of penis is still unclear. Aim The study aimed to explore whether the effect of local anesthetic on the hypersensitive and nonsensitive areas of the penis is different in premature ejaculation. Methods Penile neurophysiological tests were performed on 290 patients with primary premature ejaculation. The sensory threshold, latency, and amplitude were recorded before and after the topical application of a local anesthetic (lidocaine cream) on the penis. Outcomes Local anesthetics increased the sensory thresholds of hypersensitive and nonsensitive areas of the penis without difference but only prolonged the latency of the hypersensitive areas. Results According to the neurophysiological results, 149 of 290 patients with primary premature ejaculation had normal penile sensitivity and 141 had penile hypersensitivity. While penile hypersensitivity does not necessarily mean that the whole penis is hypersensitive, and may be that only a part of the penis is hypersensitive, and we examined the following hypersensitivities: glans hypersensitivity only (14 cases), shaft hypersensitivity only (77 cases), and whole penis hypersensitivity (50 cases). Local anesthetics (lidocaine cream) increased the sensory thresholds of hypersensitive and nonsensitive areas of the penis without difference (P < .001) but only prolonged the latency of the hypersensitive areas (P < .001), and the latency of the nonsensitive areas was not different (P > .05). Clinical Implications The present discovery implies that it is possible to improve ejaculation by applying local anesthetics externally to the hypersensitive areas of the penis to reduce the afferent local sensory signals, and improve intravaginal ejaculation latency time through accurately decreasing penile sensibility. Strengths & Limitations This is the first large-sample study to explore the difference of local anesthetics’ effects on the hypersensitive and nonsensitive areas of the penis by means of neurophysiological methods in premature ejaculation. Our study exclusively examines alterations in penile evoked potential following electrical stimulation, which may not entirely encompass shifts in penile receptivity during sexual activity. Conclusion The effects of local anesthetics on the same penis varied with penile sensitivity, and can only prolong the latency of hypersensitive area of the penis. The effect of local anesthetic on the hypersensitive and nonsensitive areas of the penis is different in premature ejaculation.