Peels, Procedures & Complication Prevention
The polite art of injuring people on purpose — done well
Chemical peels are one of the oldest tricks in the book and, when done badly, one of the most reliable ways to make a patient look worse than when they walked in. They work for the same reason they harm: they injure the skin in a controlled, dose-dependent way and force it to rebuild. Pick the right depth and the patient leaves brighter, smoother, and more even. Pick the wrong one — or the wrong patient — and you have just spent twenty minutes manufacturing the very pigmentation, scarring or erythema they came to fix.
Module 9 is the procedural counterpart to everything you have already absorbed about barrier, pigmentation, infection and clinical decision-making. The biology hasn't changed. What changes here is that you are now the one holding the bottle.
The framing is simple. Superficial peels live in the epidermis and behave themselves. Medium-depth peels reach the papillary dermis, give bigger results, and start punishing sloppy technique. Deep peels — phenol, deep TCA, full ablative resurfacing — sit firmly outside certificate-level practice, where they belong, because they can cause scarring, ectropion, pigmentary disasters and, in the case of phenol, cardiac and renal toxicity if performed irresponsibly (Lee et al., 2019).
The thesis of this module is unfashionable but true: most peel complications are not caused by the acid. They are caused by treating the wrong patient, picking the wrong agent, going too deep, or sending the patient home with an aftercare sheet they will not read. The acid is the easy bit. Everything around it is where careers quietly end.
We will cover treatment categories and depth, safe and unsafe indications, absolute and relative contraindications, the chemistry that actually matters (free acid concentration vs pH, not the marketing label on the bottle), PIH prevention in skin of colour, the periocular minefield, complication recognition, aftercare, and the consent conversation that separates the cautious clinician from the optimistic one.
Clinical Takeaway
Safe peeling is 80% patient selection, 15% aftercare, and 5% acid. Reverse those proportions and you have a complication waiting to happen.
Frequently Asked Questions
Are chemical peels safe for all skin types?
Superficial peels can be used across all Fitzpatrick types when chosen and dosed appropriately. Medium-depth peels carry significantly higher PIH risk in Fitzpatrick IV–VI and require conservative planning, photoprotection and pigment-control skincare before and after.
Should certificate-level practitioners perform deep peels?
No. Phenol, deep TCA and fully ablative resurfacing carry risks of scarring, ectropion, permanent pigmentary change and systemic toxicity. They sit firmly within specialist scope.
Key Points
- Peels are controlled injuries — depth determines both result and risk
- Most complications come from patient selection, not the acid itself
- Deep peels (phenol, deep TCA, full ablative) are specialist-only
- PIH-prone and melasma-prone skin demands conservative planning
- The acid is the easy bit — consent and aftercare are where you protect the patient and yourself
Clinical Tip
Before every peel, ask yourself one question: "If this exact patient develops PIH, an HSV outbreak or a burn, what will I do, and will I be able to defend the decision to treat?" If the answer to either half is unclear, the patient is not yet ready and neither are you.
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