Hyaluronic acid products should not be injected if allergic reactions to fillers have been observed in the past. Taking blood-thinning medication or acetylsalicylic acid (e.g. Aspirin), vitamin E, ginkgo or garlic during treatment may lead to slight bruising at the injection sites. In principle, any wrinkle or skin defect can be filled. However, if the skin defect is too extensive or large areas of the body are affected, treatment would be too expensive. In such cases other procedures are often more appropriate.
For all fillers it is important that the right substance is selected and the right layer of the skin treated with the substance. Some substances have to be injected just under the epidermis, that is in the upper dermis. Others, on the other hand, have to be injected in the lower or deep layer of the dermis. The injection is made under the wrinkle or scar and follows its line. Lip filling follows the course of the contours of the lips. For skin defects covering larger areas, filling is usually carried out in a fan or grid shape.
The injection of hyaluronic acid products is generally well-tolerated. Nevertheless in rare cases side-effects may occur which are normally only temporary. These are: skin rashes and itching, allergic reactions, infection of the site of the injection, altered pigmentation of the skin. In some individual cases headaches are experienced on the day of the injections. No long-term undesirable side-effects from hyaluronic acid are known. Toxic reactions to unintended injections have also not been observed.