Professional-C Serum — Reddit Reviews
by Obagi
Updated October 30, 2026
15% ascorbic acid serum with fast absorption; longtime HG status.
What the community says
A 15% ascorbic acid serum with a fast-sinking finish for experienced vitamin C users chasing brighter, more even-looking skin. It has loyal long-term fans, though alcohol denat., fragrance, and citrus extracts make sensitivity a real concern.
What this means for you
Backed by 13 threads from r/30PlusSkinCare, r/40plusskincare and 3 more.
Read the threads ↓What people love
- 15% vitamin C; the community calls it the OG
- Fast-sinking, lightweight feel
- Long-term repurchase appeal; three years of continued use
Watch out for
Product details
Product Traits
Key Ingredients
Based on limited Reddit discussion so far
Where to buy
What the science says
Hyperpigmentation
Some evidence
Vitamin C: 9 studies tested it directly. See all 19 studies
What the studies found
- Most studies found vitamin C helped fade dark patches, especially melasma
- It often worked better than a placebo when put on the skin for melasma
- Used with microneedling or peels, it often improved dark patches more
- Some studies found it worked about as well as other dark-spot treatments, not better
- The side effects were usually mild and brief
Anti-Aging
Some evidence
Vitamin C: 4 studies tested it directly. See all 12 studies
What the studies found
- All 4 studies that tested it directly found it helped with signs of aging
- It improved the look and texture of sun-damaged skin more than a placebo
- It helped smooth wrinkles, roughness, crow’s-feet, and uneven skin tone
- It did not clearly beat a placebo for how much water the skin held
- No irritation or sensitivity was reported in one study
Research context, not treatment advice. Studies are about the ingredient, not necessarily this exact product.
Real Reddit threads — 17 mentions across 13 threads
Obagi Professional-C Serum on Reddit, in one place — 13 threads from r/30PlusSkinCare, r/40plusskincare and 3 more, summarized.
“obagi, either 15% or 20%.”
Positive
“It feels great and sinks in so well.”
Positive
“I've tried others before, but have continued using Obagi for the past 3 years.”
Positive
“I use obagi 15% Vit C serum and it never makes me react.”
Mentioned
“I have rosacea and sensitive skin too.”
Mentioned
“Could be the combo or a personal sensitivity to an ingredient”
Mentioned
“use Exlenia Smoothing Serum and Obagi Vitamin C serum daily”
Positive
“Hi, hoping to get some advice. my eyes constantly looked tired”
Positive
“Not sure what else to try. any ideas?”
Positive
“I really like my Obagi 15% professional.”
Positive
“my Obagi 15% professional”
Positive
“I really like”
Positive
“I used to also use Vitamin C 15% by Obagi, HA5 by Skin Medica, and Plated Eye Serum.”
Mentioned
“The Obagi Vitamin C is really good. I don't think there's a good dupe unfortunately.”
Mentioned
“So I opted for the Obagi, and so far better scent-wise, a little more sensitivity with it though.”
Mentioned
“I would also add vitamin C. I use Obagi 15% professional and it works well.”
Positive
“I use Obagi 15% professional and it works well.”
Positive
“add vitamin C”
Positive
