What is a Chemical Peel?

What is a Chemical Peel?
Chemical peels use chemical solutions to loosen skin cells, ultimately improving the skin's appearance through increased collagen and decreased melanin deposits. Chemical peels are most often performed on the face, neck, chest, hands, arms, and legs.  Various strengths of chemical peels can be part of your anti-aging arsenal to
  • reduce or eliminate fine lines or wrinkles
  • correct uneven skin pigmentation
  • remove precancerous skin growths
  • soften acne scars
  • lighten or eliminate sun spots
What substances are used for chemical peels?
Chemical peels are categorized into light, medium, and deep peels, depending upon solution, strength, and time.  The substances used in light, medium, and deep peels, include alpha-hydroxy acids (AHAs), trichloroacetic acid (TCA), and carbolic acid (Phenol). The exact formula used may be one chemical or a combination.  For example, Jessner’s peel contains Lactic Acid, Salicylic, and Resorcinol.  Here is more information on each:

Light Peels - Alpha Hydroxy Acids (AHAs)
Although lights peels may also include lower strength TCA, most use alpha hydroxy acids (AHAs) such as glycolic, lactic, or fruit acids are the most superficial or mildest of the peel formulations, and they produce light peels that actually don’t normally peel but cause mild flaking.  They can provide smoother, brighter-looking skin. AHA peels may be used to
  • reduce very fine wrinkles
  • reduce uneven pigmentation
  • control of acne
  • improve texture
AHA peels may cause stinging, redness, irritation, dryness, crusting, cracking, and flaking.  Generally, no anesthesia is used for AHA peels since they cause only a slight stinging sensation during application.  Protecting skin from the sun is important following AHA peels.

Medium Peels -

A medium-depth chemical peel is “damage” to the epidermis and papillary dermis. Vehicles currently used in medium depth peels include combinations of Jessner's solution, 70% glycolic acid, and Co2 with 35% trichloroacetic acid (TCA).  The benchmark for a medium peel used to be 50% TCA. It was successful in eliminating fine wrinkles and precancerous formations; however, since TCA has a history of complications, such as scarring in strengths of 50% or higher, it is seldom used today in such high strength.  Combination products along with a 35% TCA formula have been equally effective in producing desired results without the risk of side-effects.
  • smooth fine surface wrinkles
  • remove superficial blemishes
  • correct pigment problems
  • reduce tattoo ink
  • improve stretch marks
TCA can be used on the neck or other body areas, and may require pre-treatment with AHA creams or other peeling agent. Anesthesia is not usually required for TCA peels because the chemical solution acts as an anesthetic, depending upon the concentration and time left on the skin. Multiple TCA peels may be needed over several months to obtain more refined results, and mild TCA peels may be repeated more frequently.
TCA-peel users should avoid sun exposure for several months, so plan your peels during the winter.  If you live in an area where winter doesn’t afford you that protection, plan accordingly and buy lots of good physical sunblock or sunscreen. TCA peels also produce hyperpigmentation in the skin if it is not protected.

Deep Peels - Phenol
Although 50% TCA is considered a deep peel, most doctors use phenol when deep peels are in order. Phenol is made from carbolic acid and is the strongest of the chemical peel solutions.  It yields a very deep peel. A phenol peel is primarily used to
  • correct severe skin discolorations
  • smooth out coarse wrinkles
  • remove pre-cancerous growths

Phenol should be used only on the face since scarring may result on the neck or other body areas.  Phenol is not recommended for darker-skinned individuals, and it may pose risk for patients with heart problems.  The good news is that it may permanently remove facial freckles.  And for some, another disadvantage is that the peel may cause permanent skin lightening.  Recovery is slow and complete healing may take several months and new skin may never produce pigment again, which means it will not tan, and that can be a problem. The skin will be always have to be protected from the sun.

Phenol is also included in other products designed to remove buildup of skin, such as scales from psoriasis.

The procedure:

An appropriate chemical solution is applied to the skin after patch testing to rule out allergy. The solution loosens dead cells or a layer of skin and causes it to peel or flake. The new skin is usually smoother, less wrinkled, and more even in color than the old skin, in most cases, although it may take several peels to achieve desired results.  See my page How to Apply a Chemical Peel for detailed step-by-step instructions for applying a chemical peel.

Possible problems:

Possible complications associated with chemical peels may include but are not limited to the following:

Unwanted change in skin tone color
For certain skin types, usually those with darker pigmented skin, there is a risk of developing a temporary or permanent skin color change, or an uneven color change. Hormones, such as those from birth control pills or being pregnant, can exacerbate the problem; and having a family history of melasma may also contribute.

Chemical peels can cause scarring if not applied, neutralized, or allowed to heal properly.

Fever blisters
Those people who have herpes simplex infections, also referred to as fever blisters, may experience an outbreak following a chemical peel.  You can avoid this by taking appropriate medications.

At-home Chemical Peels:

I would never use any peel solution stronger than 50% TCA, and I wouldn't use that strength on a large area. 50% TCA can be effective to remove skin tags, moles, or other growths that have been confirmed as non-cancerous by a qualified healthcare provider. I do not advise anyone to perform at-home chemical peels. Always see a qualified, board-certified healthcare provider. This is simply a blog of my experience.