I couldn't find anything that said it was ok to use both. But, I'm sure I would only take one of these and not both (too much of a good thing can be bad).
Policosanol is a chemical most often obtained from sugar cane, plants or wheat. Why take a chemical compound when garlic is natural, just my thoughts.
Have you tried Apple Cider Vinegar, 2 teaspoons a day with apple juice or tea and hone reduces cholesterol, the Vietnamese have used it for years.

I actually started taking a capful of apple cider vinegar about a week ago for my gastritis