As long as the shoulder slimming injection is not injected in excess (more than 200 units in a single area), there will be no significant side effects. Shoulder thinning injection is only localized injection, the whole treatment process is about ten minutes. After 8-10 days of local injection, you will feel a significant decrease in shoulder strength, and within one month, you can notice muscle atrophy, and the effect of shoulder slimming will gradually appear. The effect of shoulder thinning injection is maintained for the same time as that of face thinning injection and leg thinning injection, roughly 6-8 months, if you want to maintain a longer period of time, timely supplemental injections can be. The main ingredient of the shoulder injection is botulinum toxin, which is injected into the main muscle of the shoulder, that is, the trapezius muscle, which can make the trapezius muscle get wasteful atrophy, that is, no movement, slowly atrophy to achieve the purpose of slimming the shoulder. If the shoulder injection is not done properly, it will cause some corresponding risks and hazards. The surrounding injection environment, as well as in the injection operation, do not pay attention to the aseptic operation, very easy to cause wound infection. When injecting, if the injection touches the surrounding blood vessels, it will cause bruising. In addition, the injection of shoulder thinning needle is too little, can not achieve the effect of shoulder thinning. If injected into the neighboring other muscles, it will cause other muscles to atrophy accordingly. Also, when injecting too much, the whole shoulder will be lifted up and there will be a laborious feeling when lifting the arm. Shoulder injection time is too large, the number of injections is too frequent, it is easy to produce some botulinum toxin antibodies in the body, so that the injection may not be very good botulinum toxin effect, the above is the main hazards of shoulder injection.