Abstract Introduction The penis is often seen as a symbol of masculinity and sexual prowess, making its size a significant concern for many men. This has led to a search for new possibilities for increasing penile circumference and length. The demand for safe, minimally invasive procedures has made tissue filler injections popular for penile augmentation. Hyaluronic acid (HA) has been widely used since 2003. HA, a natural substance in mammalian cells, offers benefits such as anti-inflammatory and antioxidative properties, and it maintains tissue hydration and turgidity. It is utilized in various medical fields due to its favorable biomechanical properties and hypoallergenic nature. Hyaluronic acid appears to be a secure option with promising results. This study describes a technique using HA filler for penile girth augmentation in men dissatisfied with their penis size. Objective The aim of this study is to describe a new approach to penile filling with hyaluronic acid through a series of 100 cases. Methods A total of 100 patients were selected to undergo the hyaluronic acid penile filling Bastidas protocol. All patients signed the informed consent form. All subjects underwent the same protocol, using the same material and a total of 10 mL of hyaluronic acid. All measurements were taken by the same urologist, and patients returned after 30 days for further evaluation. Measurements of flaccid penis length and girth were taken before, immediately after, and 30 days post-procedure. Satisfaction levels were assessed 30 days post-procedure using a 0–10 scale. The procedure begins with local asepsis using a 2% aqueous chlorhexidine solution and an anesthetic block with a 2% lidocaine solution. The penis is marked with longitudinal lines around the urethra and six equidistant segments on the dorsolateral aspect (Fig. 1). A cannula is used to inject the HA filler in small boluses, totaling 10 mL. Patients were instructed to observe sexual abstinence for 72 hours and to perform specific massage techniques. Patients with sexual dysfunction or those using anticoagulants were excluded from the study. Initial penile size was not used as an exclusion criterion. Results Between July 2024 and July 2025, one hundred men, aged 20–59 years, underwent the procedure. The average stretched flaccid penile length was 12.6 cm, and the pre-procedure girth averaged 8.38 cm. The penile girth increased by 1.1–2.5 cm, with a mean value of 1.47 cm, immediately after the procedure. After 30 days, the mean penile girth increase was maintained at 1.38 cm. Seven patients needed minor corrections. No major complications were reported, and the mean satisfaction score was 8.7. Conclusions Hyaluronic acid (HA) is an effective method to increase penile girth. While the increase in length was observed in all patients, this study focused primarily on girth. The Bastidas protocol utilizing HA filler demonstrated reproducibility, yielding high satisfaction rates among patients without significant adverse effects. Disclosure No
G Bastidas (Mon,) studied this question.