How to layer acids without wrecking your barrier
More actives is not better. Here is the rule of three that stops over-exfoliation before it starts.
The rule of three
You do not need more than three active steps in a single routine. Cleanse counts as one active if it contains an acid. Toner counts as one. Serum counts as one. Moisturiser is not usually counted. Beyond three, you are stacking exfoliation on already-exfoliated skin, and the barrier starts to leak water.
Alternate, do not compound
If your cleanser has Salicylic Acid, your toner does not need to. If your serum has AHAs, skip the acid toner that night. The kits are already balanced this way; if you add outside products, subtract one of ours to keep the load steady.
Signs of over-exfoliation
Tightness, stinging with plain water, sudden shiny patches, breakouts in new places. Stop all actives, use only a bland cleanser and a barrier cream for 5 to 7 days. Then reintroduce actives one at a time.
AHA + BHA + PHA Kit
The resurfacing routine for texture, dullness and uneven tone