Go for the patented versions whenever possible

An ingredient called Citrus Aurantium has gained in popularity in recent years in the weight loss community, mainly because of reports surfacing that it can stimulate the metabolism and increase energy levels without causing the side effects of stimulants like Caffeine. Also known as Bitter Orange Extract, products that use this ingredient might be decent, but there may be better options.

Advantra-Z is the name of the only patented form of Bitter Orange Extract available as of this post, and you won't find it in too many supplements. A product called MeltRX 24 Ultra is billed as an "unrivaled and unmatachable fat burning appetite suppressant." However, it contains Bitter Orange Extract instead of Advantra-Z, and I don't see any ingredient that qualifies the company's claim that this product can suppress the appetite.