The biggest risk with collagen treatments is an allergic reaction. But you can avoid this by taking a skin allergy test. Other risks or side effects may include:

• Abscesses
• Infection
• Lumpiness
• Open sores
• Reactivation of cold sores (herpes)
• Scarring
• Skin necrosis (dead skin)
• Skin peeling
• Uneven skin texture

You may experience some swelling and bruising for the first 24 hours following collagen injections. The area may appear red for a day or up to a week.

It's OK to use makeup anytime, just take care not to rub the treated area. Avoid strenuous exercise, sun and drinking alcohol during the first week after the injections.

Call the doctor. If you experience any sort of sudden, severe pain or any symptoms that seem unusual, call your plastic surgeon immediately.

In the long term

Generally you can expect that the effects of a collagen injection will last about three months, though some people have reported that the effects lasted up to two years. The results of collagen injections are not permanent. Your body will eventually reabsorb the collagen, so follow-up appointments are necessary.

If you decide not to re-treat, your appearance will return to its original condition. Wrinkles and scars will return, and plumped lips will lose volume.