The Review
Peter Thomas Roth Potent-C Power Serum Review
A close look at Potent-C Power Serum: 20 percent THD ascorbate with declared vitamin E and ferulic acid levels, a rich pump texture, and who it suits best.
How this review was made: from the manufacturer's published formula and specifications, the live Amazon listing, and recurring themes in owner commentary. Eclat Press does not claim hands-on testing it has not done, and publishes no scores.
The formula, number by number
The listing declares 20 percent THD ascorbate, an oil soluble form of vitamin C that the brand positions as far more stable than traditional vitamin C, supported by 3 percent vitamin E and 2 percent ferulic acid. Those supporting levels matter: in most serums the antioxidants beside the headline active are present in undisclosed traces, while here they are part of the specification. Squalane and sodium hyaluronate appear in the ingredient list, which explains the moisturising character owners describe. The formula is fragrance free and gluten free, as printed in the listing materials.
Texture and daily use
Expect a serum with body. The pump delivers a measured dose, the texture spreads like a light lotion, and the finish is cushioned rather than watery. In a morning routine it sits comfortably under moisturiser and sunscreen for normal and dry skin. Oily skin owners are the consistent exception in owner commentary, finding the finish richer than they want in warm weather. The brand directs one to two pumps to clean, dry skin, twice daily, across face, neck and the backs of hands.
What owners keep saying
Three themes recur. Owners praise the glow and the look of more even tone that builds with steady use, they praise the pump for hygiene and repeatability, and they praise the absence of the oxidation anxiety that follows pure vitamin C around. The complaints are equally consistent: the texture is too rich for some, the bottle hides how much is left, and purists note that THD ascorbate is a different ingredient from the L-ascorbic acid they originally went shopping for. None of these are surprises once the form is understood, which is why the form decision comes first in this edit.
Where it sits among its rivals
Against Sunday Riley C.E.O., Potent-C is the stronger and more transparent formula, while C.E.O. is the more indulgent experience. Against Obagi Professional-C 20%, the choice is philosophical: stabilised breadth against pure form intensity. Potent-C wins the best overall slot because most readers are better served by the serum they can use daily without ceremony, and its label honesty sets the standard the rest of the edit is judged by.
Potent-C is the easiest top pick this edit produced, because it does the simplest thing well: it prints everything.
From the verdict
In Owners' Hands
Recurring themes, in aggregate and without numbers we cannot stand behind.
What owners praise
- The cushioned texture, which many owners describe as a serum and light moisturiser in one step
- A visible glow and more even looking tone with steady morning use
- The hygienic pump and the absence of a dropper to handle
What owners question
- The texture reads as too rich for some oily and combination skin owners
- The bottle gives little warning before it runs out
- Some owners prefer the feel of a classic water based vitamin C and find this one different from what they expected
Consider Instead
Sunday Riley C.E.O. 15% Vitamin C Brightening Serum
Choose C.E.O. if the experience matters as much as the specification: a lighter 15 percent THD formula with a famous glow and a citrus scent.
Obagi Professional-C Serum 20%
Choose Obagi if pure L-ascorbic acid at 20 percent is the point, and your skin is experienced enough to handle it.
Questions, Answered
Is THD ascorbate the same as pure vitamin C?
No. THD ascorbate, short for tetrahexyldecyl ascorbate, is an oil soluble vitamin C derivative. It is valued for stability and a gentler feel, and the skin converts it toward active vitamin C after application. Readers who specifically want L-ascorbic acid itself should choose one of the pure formulas in this edit instead.
Can Potent-C be used twice a day?
Yes. The brand directs one to two pumps to clean, dry skin twice daily, on face, neck and the backs of hands. If your skin is new to strong vitamin C in any form, begin once a day and let tolerance, not the label, set the pace of the first fortnight.
Keep Researching
Every page in the Vitamin C Serums edit.
- 01Vitamin C Serums: the hubHub
- 02Best Vitamin C Serums 2027Best of
- 03Vitamin C Serums for Sensitive SkinGuide
- 04Vitamin C Serums for the Look of Dark SpotsGuide
- 05Vitamin C and Ferulic Acid SerumsGuide
- 06Sunday Riley C.E.O. 15% Vitamin C Brightening Serum ReviewReview
- 07Obagi Professional-C Serum 20% ReviewReview
- 08Peter Thomas Roth Potent-C Power Serum vs Sunday Riley C.E.O. Brightening SerumComparison
- 09La Roche-Posay Pure Vitamin C12 Serum vs Caudalie Vinoperfect Brightening SerumComparison
- 10Vitamin C Serums Buying GuideBuying guide
- 11Vitamin C Serum Care and KeepingCare
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