It is fine to cover multiple scars when you suction. Remember the reason for suction is to create a bruise. You would thus spend the seconds as described in the FAQ - Subicsion section overlapping coverage. If it causes you any reaction, stop. Some are prone to things like raised scars called hypertrophic scars or grandulmoas formations. It should then go down on it's own and you can massage it. Concealer over it is fine. If your on any sort of blood thinning meds or excess foods (looks up those) then it can cause bruises "easier."

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