Yes. The ingredients in CircO2 have a long history of safety. What’s more, we have thousands of customers who have taken it and we have never received reports of serious side effects. That said, one of the benefits of this exclusive formula is that it relaxes the blood vessels and improves blood flow. So people who have low blood pressure should consult with their physician before taking CircO2.
Many people can feel an effect in just a few minutes. For others it takes longer. And some people say they noticed some changes in the first couple of days, and then even more benefits after taking it for a week or two. So each person responds differently. If you don’t notice an immediate difference, we recommend you keep taking it until you finish the box and then see how you feel. You’re protected by my “down to the last lozenge” guarantee. So if you aren’t completely satisfied, you can get a full refund (as long as you return it within 90 days of your purchase).
No, CircO2 doesn’t contain any caffeine … or any other ingredient that can give you an artificial energy jolt. Instead, CircO2 helps improve your blood flow. So all you feel is the natural high energy you had when you were younger.
Many people get great results taking just one tablet in the morning. But we suggest you take CircO2 twice a day for the first week or two. After that, you can try just taking it in the morning and seeing how you feel.
First, keep doing what you’re doing! You’re setting yourself up for continued great health, even as you age. But even if you’re maintaining healthy habits, the fact is that endothelial function decreases with age. Luckily, CircO2 helps protect your endothelium. And since there’s absolutely no downside, you can take it and know that it’s helping to keep you healthy as you get older.
You can purchase CircO2 directly from the official product website—that’s the only reliable and authentic source for this nitric oxide supplement. Buying from the manufacturer ensures you get the genuine formula, access to the 90-day money-back guarantee, and any current discounts or bundle pricing.



