Dear Dr. G,I am a 25-year-old man who is currently at the peak of my career. While I have a great job, I often get asked why I have not engaged in any romantic relationships. The truth is, I feel somewhat apprehensive about intimacy because I consider my penis to be somewhat deficient.Don’t get me wrong; I am reasonably happy with the length of my penis. However, the real issue I’ve struggled with since puberty is that it appears long and thin. I have consulted online resources and attended a specialist clinic, both of which have assured me that my penile girth is within the normal range. However, I believe I would be happier and feel more confident if my penis were bulkier.I have read about the old methods of using penile bulking agents, such as paraffin, which have given injectable treatments a bad reputation due to complications. However, I know that recent advances in medical aesthetics, particularly in facial fillers, have been successfully applied to the penis.I understand that using fillers for penile bulking is an off-label application, but I am willing to take the risk of complications in exchange for a bulkier girth.So, I am putting Dr G on the spot before embarking on this treatment.Specifically, what bulking agents are used for penile enhancement?What complications should I be aware of?What advancements and research have been made in the use of fillers for bulking?Finally, what efficacy and complications might I expect if I decide to proceed with the treatment?Yours truly,Bulking Billy Injection of bulking agents in the penis has evolved over more than a century, reflecting changing attitudes toward aesthetics, sexuality, urological function, and medical safety. Historically, attempts at penile enlargement through injectable substances date back to the late nineteenth and early twentieth centuries, when paraffin and other early synthetic materials were used in soft-tissue augmentation. These early experiments were driven largely by the desire to improve appearance, restore tissue loss, or enhance perceived masculinity. However, they were fraught with serious complications, including granuloma formation, chronic inflammation, migration of material, and tissue destruction. In the mid-twentieth century, liquid silicone and other oils were used in parts of Europe, Latin America and Asia, often outside regulated medical practice. While initially believed to be inert, liquid silicone and non-medical oils frequently triggered severe foreign-body reactions, chronic infection, ulceration and disfigurement that required major reconstructive surgery. The modern era of penile bulking emerged in the 1990s and 2000s alongside the rise of medical-grade dermal fillers in cosmetic dermatology. Materials such as hyaluronic acid, calcium hydroxylapatite, poly-L-lactic acid, and other collagen stimulators began to be used off-label in the penis, primarily to increase girth rather than length. Hyaluronic acid, in particular, gained traction because it is reversible, resorbable, and familiar to aesthetic practitioners, allowing for more predictable outcomes compared with permanent synthetic substances. Although such fillers were designed for facial aesthetics, their adaptation to penile augmentation represented an attempt to offer a minimally invasive alternative to surgical girth enhancement. Penile bulking also intersects with traditional urology in a different context, where peri-urethral bulking agents have been used for decades to treat urinary incontinence by increasing tissue resistance and sphincteric coaptation. The prevalence of cosmetic penile bulking is difficult to measure because many procedures occur outside regulated health systems. Nevertheless, it has become a small but growing niche within men’s aesthetic medicine, driven by increasing visibility of cosmetic procedures on social media and the normalisation of minimally invasive interventions. Men seeking these treatments often report dissatisfaction with penile size despite being within normal ranges, with psychological drivers such as anxiety, low self-confidence, and perceived performance pressure playing significant roles. Short-term efficacy studies suggest increases in penile girth that may range from modest to moderate, depending on filler type, volume, and technique, with hyaluronic acid generally lasting six months to over a year before gradually resorbing. Patient satisfaction rates are often high in the early months following treatment. The risks and complications associated with penile bulking reflect the sensitivity and anatomy of the organ. Early complications include swelling, bruising, pain, infection, and hematoma. More serious but rare acute events, such as vascular compromise, can lead to tissue ischemia and necrosis if not promptly recognised and treated. Intermediate and late complications include palpable nodules, asymmetry, migration of material into adjacent tissue planes, chronic pain, sensory disturbances, and foreign-body granulomas. Chronic infection, ulceration, scar formation, and fistula development can emerge months or years after injection. In severe cases, complications may require debulking, excisional surgery, or complex reconstructive procedures involving grafts or flaps, and even then, cosmetic and functional outcomes may remain suboptimal. Ethical and regulatory considerations surround the practice, particularly with respect to informed consent and patient selection. Because penile size concerns can overlap with body dysmorphic disorder and other psychological issues, screening and counselling are essential. Patients must be informed about the temporary nature of most safe fillers, the possibility of requiring repeated treatments, and the potential for irreversible complications. Ultimately, the injection of bulking agents in the penis remains a procedure that straddles the boundary between medical treatment and aesthetic demand. While advances in biomaterials and technique have improved the safety profile compared with historical practices, long-term data remain limited and the risk–benefit balance must be assessed carefully, with a clear understanding that even seemingly minor injections can carry lasting consequences for function, appearance, and sexual health. The renowned American philosopher Ralph Waldo Emerson once said, “Greatness has no fixed girth; it widens with every act of courage.” Men who feel dissatisfied with the size of their penis often put Dr G on the spot about injectable enhancements. His advice is simple: “Allow your fixed girth to grow into greatness with every courageous action!”