It came with the supplement, so I gave it a try. I used it without reading the instructions at all, not realizing it was a firming serum, so I was surprised by how tingly it was. When I spread it, it tingled quite a bit, especially around my eyes and cheeks. I endured it for a bit, but the tingling continued even when I applied the cream afterwards, and even when I applied the lotion the next morning. It was my first needle-type serum, and it was too irritating for me, so although I still have one more sample, I won't be repurchasing it. (My skin is quite sensitive and prone to irritation during hay fever season, but it generally doesn't irritate during this season.)