When it comes to the safety of hyaluronic acid injection, it is necessary for the partners to know the past life of hyaluronic acid. Hyaluronic acid (hyaluronicacid), also known as hyaluronic acid, glass glyoxylate, is a glycosaminoglycan composed of the basic structure of disaccharides (D-glucuronic acid and N-acetylglucosamine). Hyaluronic acid is widely found in human connective tissue, epithelial tissue and neural tissue, and is an acidic mucopolysaccharide, which is one of the main components of the extracellular matrix. With its unique molecular structure and physicochemical properties, hyaluronic acid shows a variety of important physiological functions in the body, such as lubricating joints, regulating the permeability of blood vessel walls, regulating proteins, water-electrolyte diffusion and operation, and promoting wound healing. Especially important is that hyaluronic acid has a special water retention effect and is the best moisturizing substance found in nature, known as the ideal natural moisturizing factor. Studies have found that the maturation and aging process of human skin also changes with the content and metabolism of hyaluronic acid, which can improve skin nutrient metabolism, make skin soft, smooth, remove wrinkles, increase elasticity, prevent aging, and be a good transdermal absorption promoter at the same time as moisturizing. Used in conjunction with other nutrients, it can have a more desirable effect of promoting nutrient absorption. It can be seen that hyaluronic acid is one of the basic components in human tissues, therefore, hyaluronic acid injection is safe. The safety of hyaluronic acid as a material for enlargement itself has been explained in detail above, so let’s examine the injection operation itself. Let’s start with the picture: this is a cross-sectional view of the penis, does it look complicated? There is a feeling of having a small but complete penis. If you do not have excellent medical skills and practical experience, the consequences of injecting in such an intricate environment are unthinkable. Based on my years of experience with injections, the side effects that my partners are concerned about are nothing more than the following: 1. Will it affect or impair erectile function? The level of hyaluronic acid injection is outside the subcutaneous fascia layer of the penis, i.e., the cavernous body. As long as the injecting doctor is familiar with the local anatomical level and is skilled, it is almost impossible to damage the cavernous body, so it will not affect the normal erectile function. However, if the injecting doctor lacks the relevant knowledge and practical experience and mistakenly injects hyaluronic acid into the corpus cavernosum, it may lead to hematoma in mild cases and may indeed impair the erectile function in serious cases. Therefore, it is especially crucial to choose a professional doctor in a regular hospital for injection. 2.Will it affect the hardness of erection after erection? As I mentioned in my previous article, the principle of hyaluronic acid injection for thickening can be understood as thickening the subcutaneous tissue layer of the penis and putting a thick “coat” on the dingus. Hyaluronic acid injections do not affect the spongy tissue, so the hardness of the penis after erection is closely related to the texture of hyaluronic acid. At present, medical hyaluronic acid can be divided into three categories: low molecular, medium molecular and high molecular, however, this is an agreed name, which is not strictly speaking accurate, but since this name has been deeply rooted in people’s hearts, so let’s follow it. As we know, with the increase of “molecular weight”, the texture of hyaluronic acid becomes harder and more suitable for filling operation. According to my personal operating experience, both medium and high molecular hyaluronic acid can be used for thickening treatment. Under the premise of equal injection, the effect of high molecular hyaluronic acid on hardness is smaller and almost negligible, but the only disadvantage is that the price is slightly higher than medium molecular hyaluronic acid. 3.Will there be foreign body feeling after injection? This question is more vocal for friends who have injected hyaluronic acid in my place. According to their feedback, after 1 week of edema, they did not find any foreign body sensation at the injection site. Theoretically, hyaluronic acid, as one of the components of human tissues, is not antigenic, allergenic or pathogenic, and under the premise of reasonable injection, no foreign body sensation will occur. 4.Will the appearance be unnatural after injection? In my personal opinion, the so-called unnatural appearance is the loss of harmonious beauty, and the most common situation is that it is too much. Although hyaluronic acid is an excellent material for penis enlargement by injection, excessive injection will definitely cause the local tissues to be too bloated and disproportionate to the head of the penis, resulting in an obvious sense of dissonance. Therefore, in addition to having excellent injection techniques, doctors also need to have aesthetic training to precisely grasp the injection dosage and pinpoint the balance between natural appearance and enlargement effect. In 2019, a Korean scholar published an article in TheJournalofSexualMedicine. AComparisonoftheEfficacyandSafetyBetweenHyaluronicAcidandPolylacticAcidFillerInjectioninPenileAugmentation:AMulticenter,Patient/ Evaluator-Blinded,RandomizedTrialThis paper examines the comparative efficacy and safety of hyaluronic acid and polylactic acid injections in penile augmentation in a multicenter randomized controlled study. The study compared the subjects’ satisfaction with penile appearance before and after hyaluronic acid injection. The satisfaction scores of the subjects increased rapidly after the injection and were at a high level until the end of the follow-up period, with more significant changes in the scores of the hyaluronic acid injection group. 5.Does hyaluronic acid flow and deform in the body? From the physical nature, hyaluronic acid does have mobility, and the concern of flow and deformation in the body after injection is not unfounded. But at the same time, we need to know that there is a big difference between hyaluronic acid outside the body and inside the body. After hyaluronic acid is injected into the body, after a shaping period of 2 to 4 weeks, it will form a fibrous wrap in the body, or what we usually call an envelope, to avoid mobility. In addition, good injection technique can also avoid the migration of hyaluronic acid in the body. In order to avoid the displacement of hyaluronic acid in the body and improve the satisfaction of treatment, my experience is that the flow and deformation of hyaluronic acid after injection can be effectively prevented by the following points. (1) The choice of hyaluronic acid. Try to use hyaluronic acid with high cross-linkage, which has low mobility and strong shaping power, and can effectively reduce mobility from the perspective of materials. (2) The choice of injection technology. Adopting the original local anesthetic tissue swelling combined with hyaluronic acid grid injection technology can make hyaluronic acid evenly distributed in the filling area and significantly reduce the disadvantage of gathering and clumping of filling materials. (3) Proper bandaging. It takes some time for the hyaluronic acid and surrounding tissues to fuse, usually 7-10 days depending on personal experience. During this period, erection and daily squeezing may cause the flow and deformation of the filler material. Therefore, after the injection is completed, the penis needs to be properly fixed with an elastic bandage and lightly compressed bandage. As long as the above 3 points are grasped, the problem of flow and deformation will be solved immediately. 6.Will the injection affect the feeling of sex life? The dorsal nerve of the penis is mainly responsible for the transmission of male sensations during sex. For the exact location of the dorsal nerve, please refer to the figure below. During the process of hyaluronic acid injection, most of the filler is distributed in the gap between the superficial fascia and the white membrane of the corpus cavernosum of the penis, which is located below the dorsal nerve; a small portion is distributed between the skin and the superficial fascia, which is located above the dorsal nerve. Although this part of hyaluronic acid increases the distance between the dorsal nerve and the skin to a certain extent, which is suspected of weakening the nerve conduction, its effect is negligible for men with normal sexual function. As mentioned above, in an article published in TheJournalofSexualMedicine, Korean scholars also analyzed the sexual satisfaction of the study subjects before and after the injection, and the results showed that the satisfaction scores of the patients did not decrease, but increased to a certain extent after the injection. I think the reason for this is that the hyaluronic acid located between the skin and the superficial fascia plays a certain “insulating” role, which reduces the sensitivity of the dorsal nerve and therefore has a certain therapeutic effect on some patients with premature ejaculation, but whether there are other mechanisms to be further studied and explored.