What is Coenzyme-Q1-10 100mg? Coenzyme Q10 is a vitamin like substance, which is produced naturally in the human body although the amount produced declines with age. Q10 is responsible for the production of energy in muscle cells, the heart, liver & muscles being good examples. What Does Coenzyme-Q-10 100mg Do? May help to maintain & support energy metabolism, heart, muscle & immune system function.