How does it work? The specific extract being used in garcinia cambogia supplements is called hydroxycitric acid (HCA) and it works in two ways to promote. Find helpful customer reviews and review ratings for Garcinia Cambogia Burn (2 Bottles) - Clinical Strength Drink lots of water and do not take without consulting your physician. .. Hope It continues to work when I am on second bottle. Find patient medical information for GARCINIA on WebMD including its uses, How does it work? Garcinia contains the chemical hydroxycitric acid (HCA).