Can TCA Peels Be Done on the Neck As Well As the Face? If Not, is There a Line of Demarkation Between the Face and Neck?

TCA peels are something that everyone should be doing yearly to keep and get their skin looking the best it can be. A Jessner's + 25-35%TCA on the face and chest with a Jessner's +15-25% on the neck is a great combination that is easy to undergo and can make dramatic improvements in one's skin without the demarcations that the old phenol peels did yrs ago. A good prescription cortisone lotion for the 1st week or two is essential as is a good prescription bleaching cream the 2nd week with SPF sunscreens and good followup care by your doc. Sincerely, David Hansen,MD

A variety of superficial chemical peeling agents have proven successful over the years for treating such problems as fine lines and wrinkles, crepeyness,  and uneven skin pigmentation. Favorite agents for these purposes include glycolic acid in concentrations up to its maximum of 70%, Jessner's solution ( a combination of superficial acids), salicylic acid (in strengths up to its maximum) . and trichloroacetic acid in potencies between 10%-25%

In general, prefer to restrict the treatment of the neck with trichloroacetic acid to a concentration of no more than 15% and to neutralize it immediately at the first sign of frosting. When deemed appropriate the face and the neck may be treated with different agents. For example, the face may be treated with TCA 25% and the neck with Jessner's or glycolic acid, depending upon the particular needs.Treatment should only be carried out by a board certified aesthetic physician with extensive experience in the use of all peeling agents. 

TCA chemical peels can be tailored from superficial to medium in depth depending on the strength of the TCA.  Medium depth peels using TCA 25-35% are commonly used on the face, and I have never seen this cause the line of demarcation you are concerned about.  I would be reluctant to use TCA on the neck as this skin is much more prone to scarring and abnormal pigmentation.  For the neck, I would start with a light chemical peel using Jessner's solution or salicylic acid or lower strength glycolic.  The strength of the peel could be gradually increased based on the response at each visit.