- Collagen injections rarely cause serious side effects, except on the small percentage of people who are allergic to collagen (about two people out of every 100). This is prevented by performing a skin rash test prior to the application. If an allergy appears, it is often in the form of reddening or peeling of the skin. Itchiness at the site of application is also common. These symptoms usually disappear on their own after a period of several weeks.
- The risk of infection is always a possibility with any foreign substance being injected into the skin. In the case of collagen, infection can result due to improper care of the puncture site or from applying creams or other products over the injection site too soon after the application (doctors recommend waiting at least 24 hours to do so). Infections can lead to other problems, such as scarring or marks, especially if not treated immediately.
- Pain and swelling are the most common side effects of collagen injections. This is especially common the first time the injections are applied and usually go away as the skin gets used to the needles. In most cases, the pain only lasts for a few hours and should start going down soon after the application. If the pain intensifies or if the swelling seems to increase, this may indicate an infection is forming and a doctor should be consulted immediately.
- If collagen is applied over a large surface, the puncture marks caused by the needles may be visible for some time. In most cases, it will resemble an insect bite and will become invisible once the swelling subsides. If lumpiness occurs around the injection site, doctors may recommend using ice or an anti-inflammatory to help reduce the risk of infections.
- In a very small number of people, scarring may occur. This is more likely in people with light skin and those who are sensitive to invasive procedures. Abscesses are also possible, but the possibility is remote. To prevent the chance for lumps, doctors usually ask the patient to remain in their offices for at least 30 minutes, so they can monitor the look and feel of the skin after the application.
