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(881)881

Potent-C™ Power Serum

Peter Thomas Roth

Sold Out

SOLD OUT

This item is no longer available. Browse our recommendations for something similar.

Details & care

What it is: A brightening and anti-aging vitamin C serum formulated with high-potency 20% THD ascorbate, an advanced form of vitamin C that is 50 times more powerful than traditional vitamin C.

Who it's for: Ideal for all skin types. Good for those looking to reduce dullness and uneven texture, loss of firmness and elasticity.

What it does: Brightening cvitamin C serum is packed with 20% THD ascorbate, an advanced form of vitamin C that is 50 times more powerful than traditional vC. The high concentration helps defy seven signs of aging* at once, helping to visibly improve the look of fine lines, wrinkles, uneven tone, loss of brightness, loss of firmness, uneven texture and dehydration. Boosted by potent antioxidants of 3% vitamin E and 2% ferulic acid, this creamy serum is further enhanced with turmeric, ginseng, jojoba and squalane, offering a complete solution for brightening and anti-aging concerns.
*Based on a 4-week consumer perception study on 33 women ranging in age from 49 to 65.

Key ingredients:
- 20% THD ascorbate vitamin C: high-potency, brightening vitamin C that helps defy 7 signs of aging at once
- 3% Vitamin E and 2% ferulic acid: provide antioxidant benefits and help boost vitamin C performance
- Turmeric, ginseng and squalane: improve the look of uneven tone, dullness and dehydration

Research results:
Based on a 28-day consumer perception study with 35 female subjects:
- Users agree they saw an improvement in wrinkles, firmness and brightness in 7 days

How to use: Apply the serum to clean, dry skin. For best results, use twice daily on face and neck with continued use.

  • 1 oz.
  • Paraben-free; sulfate-free; alcohol-free; fragrance-free; gluten-free; formaldehyde-free; mineral oil-free; retinyl palmitate-free; oxybenzone-free; coal tar-free; hydroquinone-free; synthetic fragrance-free; triclocarban-free; triclosan-free
  • Made in the USA
  • Item #5586713
  • Core Product ID 333335CGRG

Ingredients

Water/Aqua/Eau, Tetrahexyldecyl Ascorbate, Butylene Glycol, C9-12 Alkane, Caprylyl Methicone, Tocopheryl Acetate, C10-18 Triglycerides, Squalane, Ferulic Acid, Polyglyceryl-6 Distearate, Propanediol, Hydrogenated Lecithin, Sodium Hyaluronate, Curcuma Longa (Turmeric) Root Extract, Panax Ginseng Root Extract, Jojoba Esters, Leuconostoc/Radish Root Ferment Filtrate, Coco-Caprylate/Caprate, Cetyl Alcohol, Polyglyceryl-3 Beeswax, Xanthan Gum, Sodium Phytate, Potassium Sorbate, Sodium Benzoate, Mica, Ethylhexylglycerin, Phenoxyethanol.
Ingredients are subject to change at the manufacturer's discretion. For the most complete and up-to-date list of ingredients, refer to the product packaging

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Peter Thomas Roth

Launched in 1993, Peter Thomas Roth blends ancient Hungarian health and skin care philosophies with 21st-century technologies and ingredients. Founder Peter Thomas Roth's passion for skin care grew from his family's heritage as spa owners in Hungary, coupled with a personal quest to find solutions for his own skin problems. The result is breakthrough formulas that deliver astonishing results.

Reviews

(881)8814.2 out of 5
Write a Review

Most helpful positive review

Dec 26, 2025

Another out of the park transformer!

I finally tried the PTR C serum. In three days I noticed a difference. My skin felt smoother. I still have some mild sun spots , which will take longer to disappear. I expect that. I just didn't imagine such a difference in under a week!! This is definitely a HIGHLY recommended product!
Kfallon

Most helpful critical review

June 10, 2026

Decreased Quality - Do Not Purchase

TL;DR. Packaging opens up and leaks. Product does not stay emulsified and is greasy not silky. Find an alternative Vitamin C. I've purchased this product for years and have noticed changes with time. However, my latest was the last. The packaging is poorly constructed and unscrews constantly. The first package was leaking and I had to return it. The product itself is separates and does not stay emulsified. I have to shake it before I dispense it to mix the oil and creme together, however there are no such instructions on the bottle. It seems the quality of the ingredients have decreased. Really disappointing.
JRBK

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5 stars55%
4 stars22%
3 stars14%
2 stars4%
1 star5%

Pros:

Cons:

June 10, 2026

Decreased Quality - Do Not Purchase

TL;DR. Packaging opens up and leaks. Product does not stay emulsified and is greasy not silky. Find an alternative Vitamin C. I've purchased this product for years and have noticed changes with time. However, my latest was the last. The packaging is poorly constructed and unscrews constantly. The first package was leaking and I had to return it. The product itself is separates and does not stay emulsified. I have to shake it before I dispense it to mix the oil and creme together, however there are no such instructions on the bottle. It seems the quality of the ingredients have decreased. Really disappointing.
JRBK
Dec 26, 2025

Another out of the park transformer!

I finally tried the PTR C serum. In three days I noticed a difference. My skin felt smoother. I still have some mild sun spots , which will take longer to disappear. I expect that. I just didn't imagine such a difference in under a week!! This is definitely a HIGHLY recommended product!
Kfallon
Dec 2, 2025
I loved the old power serum. It was clear and glided on my skin. Whyyyy if you say it's the same product would you not only change the packaging but also the consistency from a clear hydrating serum to a white thicker serum. Do not like the feel. You did the same thing to the wrinkle resist power serum to these white seeums. No longer a fan of this whole new set of serums. They used to make my skin glow. No longer....the consistency is different. On the hunt for new products.
SBRI
June 16, 2025

Stinks!!

Yikes it smells so bad! I tried it for the first time 6/10/25 . Smells like rotten eggs plus it came out of the bottle really thick and a wierd color yellow. I still could smell it once i put it on. Had to go into a public bathroom to wash it off.
Juju2025
May 16, 2025

Unpleasant smell

The odor of this product line is very unpleasant. I thought that this would be useful for my skin but the odor is offensive. I will be returning for a refund as I cannot use the product.
Wyobreeze
Apr 20, 2025

In love with this serum

I have owned a lot of serums throughout my adult life. PTR Potential-C is by far a superior quality than the rest. It starts with the beauty of the bottle itself, the sublime experience of rubbing in the serum. It is exquisite. The light smell and ease of application are divine. The results can be seen almost immediately. I will never use another serum again.
Verified purchase
Fannoone
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