No, as long as you take P6 Extreme as directed you should not experience any adverse side effects! P6 Extreme is a natural testosterone booster not a pro hormone or a steroid. It containes Beta-sitosterol which inhibits 5-alpha reductase, an enzyme that converts testosterone to dihydrotestosterone (DHT). By blocking DHT conversion, beta-sitosterol minimizes undesirable side effects resulting from excessive DHT levels such as male pattern baldness. P6 Extreme also contains Agaricus bisporous which has a mutagenic effect on the aromatase enzyme—the enzyme responsible for converting androgens, such as testosterone, into estradiol (estrogen).Unlike other aromatase inhibitors that only block the aromatase enzyme, this compound cleaves amino acids that make up aromatase, disabling it from converting androgens into estradiol (estogen)—blocking estrogen and thereby preventing any estrogenic side effects.