Ampoules are small bottles with highly concentrated, active treatments. The problem with highly concentrated active ingredients? They are notoriously unstable. (The more effective the active ingredient is, the trickier it is normally.) That is why ampoules are usually encapsulated in sealed glass so that they are not exposed to air that can worsen the formulas. This makes for pretty powerful treatments. This also means that they don't need high-performance preservatives, so the formulas are simple and clean.
And they have become a trend lately. Regardless of your need, you'll usually find one that's tailored for you: you'll find options with soothing phytonutrients against redness, acids for cell turnover, and moisturizers for dry skin. This Vichy LiftActiv Peptide-C ampoule serum uses phyto-peptides, a natural hyaluronic acid and a very strong vitamin C to promote collagen synthesis.