Antioxidant Serum
A daily antioxidant serum built around a stable, gentle form of vitamin C (sodium ascorbyl phosphate) with vitamin E and ferulic acid. Worn under sunscreen each morning, it helps defend sensitive skin from pollution and free radicals and supports a brighter, more even-looking tone.
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Concerns: Dullness · Early signs of aging · Environmental damage
When: AM, under SPF
☀︎ The Morning Routine
Get the full 3-step morning routine for a calm, protected, and radiant complexion and save 20%.
$103.99 value · save $20.80
- Neutralizes free radicals with stable Vitamin C and Vitamin E
- Enhances natural glow and radiance
- Ferulic Acid stabilises and amplifies the antioxidant effect
- Gentle, non-stinging form of Vitamin C
- Dullness
- Environmental Damage
- Early Signs of Aging
- Sensitivity to Vitamin C
Antioxidant Serum
Ingredients
Calming botanicals and proven actives work together to support and strengthen sensitive skin.
Fragrance-free.
Full ingredient list (INCI)
Key actives: Sodium Ascorbyl Phosphate (Vitamin C), Tocopherol (Vitamin E), Ferulic Acid. The complete INCI list is printed on the packaging.
SODIUM ASCORBYL PHOSPHATE
A stable, gentle form of vitamin C that neutralizes free radicals at a skin-friendly pH.
Read the ingredient guideNihon in real routines
Nihon hasn’t been through a consumer study yet — we won’t imply otherwise. Here’s how people use it.
In real routines
Videos from customers and creators. Tap the speaker to listen.
"Most vitamin C is L-ascorbic acid. It works — and on reactive skin it also stings, and it turns brown in your cabinet before the bottle is finished. Nihon uses the stable form."
“The glow factor of this antioxidant serum is shocking. I am frequently complimented on my dewy skin…”
Concerns & Benefits
A morning antioxidant shield for skin that reacts to conventional vitamin C: stable vitamin C, vitamin E and ferulic acid, without the acidity that causes stinging.
Your Concerns
- 01Dullness
- 02Environmental Damage
- 03Early Fine Lines
- 04Sensitivity to Vitamin C
Our Benefits
- Antioxidant protection
- Brighter, more even glow
- Stable, non-oxidising vitamin C
- No sting, no flush
- Layers under moisturizer and SPF
How to Use
Instructions
Step 1: Cleanse with KIREI on damp skin and pat dry.
Step 2: Apply 2–3 drops of NIHON to face and neck.
Step 3: Moisturize with IRO, then SPF.
Suggested Routine
KIREI · NIHON · IRO · SPF
Frequency
Daily use, AM. Morning product — that’s the whole rule.
Questions about Nihon
Straight answers, no marketing. If yours is not here, write to [email protected].
Which form of vitamin C does Nihon use?
Sodium ascorbyl phosphate (SAP), a stable, gentle vitamin C derivative, combined with vitamin E and ferulic acid. Unlike pure L-ascorbic acid, SAP does not need a very low pH to work, which makes it much better tolerated by sensitive skin.
When should I apply it?
In the morning, after cleansing with Kirei and before Iro and your sunscreen. Antioxidants do their best work under SPF during the day.
Can I use Nihon with Kido or Izumi?
Yes. Use Nihon in the morning and Kido or Izumi at night. That is exactly how the Complete routines are built.
Will it sting or tingle?
It is unlikely. SAP is far gentler than pure L-ascorbic acid. If your barrier is very compromised, start with three or four mornings a week and build up.
Has Nihon been through a consumer study?
Not yet. Kirei, Iro, Kido, Izumi and Gaman each have an independent 30-day study published on this site. We only publish results we actually have.
Is it safe during pregnancy?
Vitamin C, vitamin E and ferulic acid are generally considered compatible with pregnancy, but please confirm your routine with your doctor.
What if it is not right for my skin?
Every order on ikiskincare.com is covered by our 30-night money-back guarantee. Email [email protected] within 30 days of delivery with your order number and we will take care of it. See our Shipping & Returns page for the full policy.
How much is shipping?
Standard US shipping is free on orders over $65. Orders are processed in 1–2 business days and standard delivery takes 3–7 business days. We currently ship within the United States only.
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