The Ordinary- Caffeine Solution 5% + EGCGDescription Caffeine Solution 5% + EGCG is a water based serum that reduces the look of puffiness and dark circles in the eye contour. The formula works by combining a high concentration of caffeine with a highly purified epigallocatechin gallatyl glucoside (EGCG). In your regimen Prep Step 2: Treat Seal Use after cleansing, before water based serums, anhydrous serums, oils, suspensions or creams.