Content provided by Cleveland Clinic.

Collagen injections replenish one of the natural proteins in your skin, giving your skin a plumper, smoother appearance. To understand collagen, you should first understand your skin.

Skin consists of two layers: the epidermis and the dermis. The upper-most layer, known as the epidermis, controls the loss of water from cells and tissue. Without this protective barrier, the body would quickly dehydrate. Just below the epidermis lies the second layer, the dermis. The dermis, although it contains blood vessels, nerves, and hair follicles, is primarily made up of a protein called "collagen." This protein forms a network of fibers that provides a framework for the growth of cells and blood vessels. Because it is the primary component of the dermis, collagen acts as the support structure for the skin.

1. Why do lines appear?

In young skin, the collagen framework is intact and the skin remains moisturized and elastic. It's resistant to the many facial expressions we adopt as well as our daily environmental exposure. However, over time, the support structure weakens and the collagen support wears down. The skin loses its elasticity and tone. Every time you smile, frown or squint, you put stress on the collagen in your skin. The effect of these facial expressions is cumulative, and facial lines begin to appear.

2. Why aren't creams containing collagen enough to smooth out lines?

Collagen creams work only on the skin surface. A moisturizer with or without collagen cannot penetrate the skin and is not designed to be absorbed. No moisturizer can undo the cumulative effect of collagen loss. Creams primarily slow the rate of water loss from the skin and help keep the skin supple.

3. How do collagen injections work?

Collagen injections replenish the skin's natural collagen. The natural beauty of your skin is enhanced as the contour of the support structure is restored.

Zyderm and Zyplast are bovine-derived collagen products that replace the collagen your skin loses over time. Zyderm and Zyplast collagen are placed just beneath the skin, in the dermis where the body readily accepts it as its own.

CosmoDerm and CosmoPlast are bioengineered human collagen products that are used for similar indications as Zyderm and Zyplast but have the advantage of not requiring a skin test prior to the first treatment.
Collagen should be injected into your skin only by a trained health care professional. By supplementing your skin's own collagen, collagen replacement therapy helps smooth facial lines as well as most types of scars.

4. What can I expect?

You should expect to receive a small injection of local anesthesia to numb the area being treated. There is a possibility of slight bruising, and you may experience puffiness, redness, and tenderness around the treated site.

It's important to discuss with your physician exactly what you can expect from each treatment. Together, you can prioritize which facial areas are most important to you and discuss how many treatments you may need as well as the estimated cost. It's important to know that one treatment may not remove every line on your face; a full correction generally requires continued treatments.

5. How many collagen injections will I need?

Just like natural collagen, collagen replacements begin to lose form and will eventually wear down. Full correction occurs and is maintained only with a series of treatments.

Treatment may require collagen injections two to four times a year to maintain the smoothing effects. Depending on age, skin condition, amount of sun damage and genetics, your treatment program will be specifically tailored to incorporate your individual needs.

6. How do I find out if collagen injections are right for me?

You and your physician will discuss your medical history and the areas you want treated. Collagen injections are not app