What is MD Vitamin C Serum?

MD Vitamin C Serum is a physician-formulated, clinical-strength antioxidant serum developed by Dr. Susan Lin, M.D. It delivers a peak 20% concentration of USP-grade L-Ascorbic Acid in a stabilized, water-based matrix — the gold-standard form of Vitamin C for visible brightening, antioxidant defense, and skin-strengthening support.

Why 20% L-Ascorbic Acid instead of a Vitamin C derivative?

L-Ascorbic Acid is the only directly bioavailable form of Vitamin C — the form your skin recognizes and uses without conversion. Derivatives (ascorbyl glucoside, tetrahexyldecyl ascorbate, MAP) must be converted by the skin and deliver lower effective potency. The 20% concentration is the clinical ceiling — higher percentages don't increase efficacy and can irritate.

How is MD Vitamin C Serum stabilized?

L-Ascorbic Acid is notoriously unstable and oxidizes when exposed to light, air, and water — losing potency and turning brown/orange. MD Vitamin C Serum uses an Ionic Stability Matrix that protects the active concentration, keeping the serum crystal clear and effective through normal daily use. Store in a cool, dark location for maximum shelf life.

How do I apply MD Vitamin C Serum?

In the morning, apply 3-5 drops to clean, toned skin. Pat gently into the face and neck. Allow 60 seconds to absorb, then follow with moisturizer and SPF (essential — Vitamin C boosts the photoprotective effect of sunscreen). For sensitive skin, start every other day and build to daily use.

Can I use MD Vitamin C Serum with retinol or niacinamide?

Yes. MD Vitamin C Serum is best used in the morning. Apply Vitamin C in AM (under SPF), and retinol in PM — they target different concerns and work best on separate schedules. Niacinamide can be layered after Vitamin C in the same routine without conflict (the historical they cancel out claim has been refuted by modern research).

Is MD Vitamin C Serum safe for sensitive skin?

20% L-Ascorbic Acid is potent and can cause initial tingling on first applications. For sensitive skin, start every other day for 2 weeks, then build to daily. If you experience persistent redness, reduce to 2-3 times per week. The fragrance-free, oil-free formula minimizes additional irritation sources.

What results can I expect?

Most users see brighter, more luminous skin within 2-4 weeks. For visible fading of dark spots, hyperpigmentation, and improved firmness, expect 8-12 weeks of consistent daily morning use. Pairing with daily SPF amplifies and protects the results.

Where is MD Vitamin C Serum manufactured?

MD Vitamin C Serum is manufactured in the United States in a GMP-certified facility registered with the US FDA for cosmetic, food, and drug manufacturing, under board-certified physician oversight by Dr. Susan Lin, M.D.

MD® Vitamin C Serum

MD Ultimate 20% Vitamin C Serum for face featuring pure L-Ascorbic Acid in a professional-grade clinical bottle for anti-aging and dark spot reduction.

A woman applying MD Ultimate Vitamin C Serum to her face to treat fine lines and hyperpigmentation while providing digital blue light protection.

Close-up of MD Ultimate Vitamin C Serum showing a crystal-clear, non-oxidized dropper to demonstrate formula stability and weightless water-based texture.

MD Ultimate Vitamin C Serum in a laboratory science setting highlighting the 20% USP-grade purity and ionic delivery system for professional skin results

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MD® Vitamin C Serum

MD® SKIN

MD® Vitamin C Serum

$177.00

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Size: 30ml

30ml

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Why MD® Vitamin C Serum

20% USP-grade L-Ascorbic Acid Physician-Formulated Water-Based High-Flux Matrix Fragrance-Free Blue Light Defense Stabilized Made in USA Crystal Clear No Heavy Oils

MD® Ultimate Vitamin C: The 20% L-Ascorbic Clinical Standard

Redefine skin longevity with the purest form of Vitamin C. Unlike prestige formulas that rely on diluted derivatives and heavy oils, MD® delivers a peak 20% concentration of USP-grade L-Ascorbic Acid in a high-flux, water-based matrix. This physician-formulated serum provides instant antioxidant saturation to dismantle dark spots, neutralize digital blue light stress, and rebuild the appearance of collagen-dense skin. Crystal clear, fragrance-free, and meticulously stabilized — the professional's choice for a high-definition, ageless glow.

How to apply MD® Vitamin C Serum

Cleanse face and gently pat dry.
Apply 3–4 drops to face, neck, and décolleté in the morning.
Press into skin; allow 60 seconds to absorb fully.
Layer with moisturizer, then sunscreen (MD® Ultimate Anti-Aging Mineral Sunblock SPF 50 recommended).
Use daily for sustained antioxidant defense and brightening.

The MD® Skin clinical signature: 20% L-Ascorbic Acid at USP-grade purity, stabilized in a water-based matrix engineered for maximum bioavailability. Physician-developed by Dr. Susan Lin, M.D.

→ Full skin clinical evidence dossier

We create beauty through advanced science™

Physician-Formulatedby Dr. Susan Lin, M.D.

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30-Day Returnssatisfaction guaranteed

Peer-Reviewed SafetyJCLT 2008 (PMID 18569264)

To understand the power of MD Vitamin C, it is essential to recognize the visible impact of 20% L-Ascorbic Acid on the skin's structure.

Phase 0: The Signs of Environmental Stress

Before treatment, the skin often reflects the cumulative damage of UV exposure, urban pollution, and digital blue light.

Dullness & Discoloration: Skin appears lackluster and "tired." Cumulative oxidative stress manifests as visible sun spots, age spots, and uneven pigmentation.
Texture & Laxity: As the dermal matrix loses its structural integrity, pores appear enlarged and "stretched." Fine lines become prominent due to collagen depletion and chronic dehydration.

Phase 1: The Glow of Restored Health

After consistent use of our clinical-grade protocol, the skin transitions into a state of active recovery and defense.

Radiance & Clarity: A unified, luminous skin tone emerges. The high-potency formula targets localized melanin clusters, shattering hyperpigmentation and restoring a high-definition clarity.
Firmness & Refinement: Structural resilience is restored. Pores appear tighter, and the skin’s surface feels smoother and firmer. The refined texture evenly reflects light, creating a naturally vibrant, ageless glow.

Why the 30-Day Window Matters

Because the skin’s natural turnover cycle takes approximately 28 days, using the 20% L-Ascorbic Acid consistently for one month allows the "new" skin cells to emerge fully saturated with antioxidants. This ensures that the results you see aren't just surface-level—they reflect improved skin health from the inside out.

Experience the gold standard of anti-aging. Powered by 20% stable L-ascorbic acid, this clinical-strength serum brightens, firms, and smooths skin in just 30 days. Unlike other serums, our formula stays clear, never oxidizes, and is gentle enough for sensitive or Retin-A treated skin.

• 20% Gold-Standard Concentration, Clinically Potent
Utilizes the dermatological “gold standard” of 20% L-ascorbic acid to powerfully stimulate collagen regeneration, fade dark spots and acne marks, and defend against free-radical damage.

• Exclusive “Zero-Oxidation” Stabilization Technology
Unlike vitamin C products that easily turn yellow and lose potency, MD® employs an ultra-stable formula. Even after one year of opening, every drop remains clear and fully active.

• A Boon for Sensitive Skin and Retin-A Users
Features a pH-balanced, non-irritating base, making it safe for fragile skin undergoing Retin-A (tretinoin/retinol) treatment. Enjoy true renewal without redness.

• Combines Fast-Acting and Long-Lasting Effects
Visibly improves uneven skin tone, enlarged pores, and skin laxity within just 30 days.

Clinical-Strength Vitamin C, Engineered Without the Oxidation

20% L-Ascorbic Acid stabilized in an exclusive zero-oxidation formula — the dermatological gold standard of anti-aging, gentle enough for sensitive skin and patients on Retin-A.

MD® Vitamin C Serum delivers what most vitamin C serums promise but few achieve: 20% L-Ascorbic Acid — the dermatological gold standard concentration — in a formula that stays clear and fully active for over a year after opening. Unlike traditional vitamin C serums that oxidize, turn yellow, and lose potency within weeks, MD's exclusive stabilization technology preserves every drop's clinical efficacy.

This high-potency dose of pure Vitamin C powerfully stimulates collagen regeneration, fades dark spots and post-acne marks, and defends against free-radical damage. The pH-balanced, non-irritating base is gentle enough for fragile, reactive skin — and one of the few high-strength vitamin C serums safe for patients undergoing Retin-A (tretinoin/retinol) treatment.

Within 30 days, expect visibly firmer skin, brighter complexion, and even tone — without redness or irritation, even on sensitive skin.

User Proven Results

Real Stories, Remarkable Results

This serum gives you the radiant glow you've always dreamed of, without any stinging sensation! It's a true savior for sensitive skin. Pores visibly shrink, and makeup applies more smoothly. With consistent use, your skin will achieve:
• Brighter: Fades dark spots, improves uneven skin tone and dullness.
• Firmer: Smooths fine lines and wrinkles, boosts skin elasticity.
• Smoother: Minimizes enlarged pores, refines skin texture.
• Stronger: Protects against UV damage and free radicals, builds a stronger skin barrier.

Key Ingredients: The MD^® Clinical Matrix

Powered by Science, Perfected by Nature
Our formula combines the highest concentration of clinical-grade actives with potent botanical stabilizers to deliver results without compromise.

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· 20% L-Ascorbic Acid — The dermatological gold standard concentration of pure Vitamin C. A potent antioxidant that strengthens skin's natural defense, stimulates collagen, fades dark spots, and visibly reverses photoaging.

· Zero-Oxidation Stabilization Technology — MD's exclusive formula remains clear, potent, and fully active for over a year after opening, unlike traditional vitamin C serums that oxidize within weeks.

· pH-Balanced, Non-Irritating Base — Engineered to be safe for sensitive, reactive skin and patients on Retin-A (tretinoin/retinol) treatment.

✨ Result: Skin appears firmer, brighter, and more even-toned within 30 days — without redness or irritation.

How to Use

Maximize results with a precise application protocol.

Professional Protocol: How to Use

1. PREP: Begin with a thoroughly cleansed and slightly damp face. For maximum bio-availability, ensure no residue from oil-based cleansers remains.

2. DISPENSE: Place 3–5 drops into the palm or onto fingertips. The water-based matrix has high molecular mobility, so a small amount is sufficient to cover the entire treatment area.

3. ACTIVATE: Press the serum into the face, neck, and the backs of hands using firm, upward motions. Avoid the immediate eye area. The "Press & Roll" technique ensures the 20% L-Ascorbic Acid reaches the deeper dermal layers.

4. THE ASCORBIC GAP: Allow 10 minutes for the serum to fully penetrate and for the skin’s pH to calibrate. This "activation window" ensures the 20% concentration is locked into the skin’s reservoir before it is sealed by subsequent products.

5. SEAL: Follow with a broad-spectrum SPF in the morning or a lipid-rich moisturizer in the evening.

Tip: A brief tingling sensation is a clinical sign of the 20% L-Ascorbic Acid optimizing your skin’s pH environment. This typically subsides within 3–5 days as your skin’s resilience increases. A slight tingling sensation may occur during initial use.

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Woman on a sunny beach using a non-greasy beach SPF. This sweat-resistant mineral shield for sensitive skin provides broad-spectrum UVA/UVB protection without a white cast.

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Clinical ingredient breakdown of reduced L-glutathione, vitamin C, and alpha lipoic acid

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Clinical and User Trials

Frequently Asked Questions

Because MD® Vitamin C s a pure water-based formula without irritating Ferulic Acid or synthetic fragrances, it is an excellent post-procedure antioxidant. Once the skin barrier has closed (typically 48–72 hours post-treatment), applying our 20% L-Ascorbic Acid helps provide the essential building blocks for collagen synthesis and prevents post-inflammatory hyperpigmentation.

High-Energy Visible (HEV) light from screens generates oxidative stress that leads to "digital dullness" and collagen breakdown. Clinical-grade 20% L-Ascorbic Acid acts as a molecular shield, neutralizing the specific free radicals triggered by blue light exposure. This makes it an essential daily treatment for professionals in high-tech environments.

To ensure maximum bioavailability. L-Ascorbic Acid requires a specific acidic pH (approx. 2.7) to penetrate the skin barrier. Applying a moisturizer (which usually has a neutral pH) too quickly can "buffer" or neutralize the Vitamin C before it reaches the dermis. The 10-minute "Ascorbic Gap" allows the serum to fully saturate the skin's reservoir for 72-hour protection.

While 20% is the maximum clinical strength for Vitamin C, MD® Ultimate is formulated with a high-flux water-base rather than heavy oils, which reduces the "trapped" heat sensation often associated with irritation. While a slight tingling is a normal sign of Active Saturation, our formula is designed to deliver high-potency anti-aging results with a focus on skin-barrier compatibility.

Clarity is the ultimate indicator of antioxidant stability. Many Vitamin C serums use Ferulic Acid or synthetic dyes to mask oxidation (turning orange or brown). MD® Ultimate is meticulously stabilized through a physician-formulated ionic matrix, ensuring the 20% L-Ascorbic Acid remains crystal clear and 100% bio-active for up to 12 months. If a serum is yellow, it has already begun to lose its potency.

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Feels Like A Facial Oil-Moisturizing, Boring Package, Bottle Leaking On Arrival-Not Sealed Properly

Do I think this is a bad serum? No Do I think it is excellent? Also no. So far, I think it is okay. I haven’t noticed any amazing results, but I think I need to use more consistently and pay closer attention. This is the first vitamin c serum I have used that feels oily. It isn’t excessively oily so doesn’t bother me, just an observation. It feels like a thin facial oil that absorbs well. It feels moisturizing. There is no detectable scent. The packaging is very plain and boring compared to others I have used. This is fine, but it is rather expensive, so I was surprised to see such a boring bottle. It is a dark glass with a dropper lid which is nice. My major complaint about the packaging is that it arrived feeling oily on the outside. I could tell some product had leaked out somehow- not cool especially considering the price. Also the product was poorly sealed. The plastic to seal covered the glass bottle and didn’t extend up to cover the dropper. Someone could easily have tampered with this. Both those issues should be fixed as it doesn’t seem to be an isolated incidence. I did see some other reviews mention the same thing. Overall, I like the way the serum feels on my skin, but haven’t noticed any real changes other than maybe my skin feeling somewhat moisturized after using. I haven’t had any irritation from using on my sensitive skin. I’m going to try to use this very consistently and regularly for awhile to see if I notice anything as I do have some dark spots that I would love to be gone. I’ll be sure to update this review if any issues arise or I have comments to make. As of now, this product seems fine, but is not a good value for me at all for the price since I haven’t noticed results. I hope my review was helpful in some way, and if so, I would love to know-thanks!

Works great, but arrived leaking

My wife swears by vitamin C serum, and after a few months of using it I’m firmly on board. In the last few months my skin has visibly plumped, and flaws like crow’s feet - which always look their worst when I’m hungover and dehydrated - have noticeably smoothed out. I’d usually give 5 stars to any vit C serum that did the job as promised, but I have to mark this down a star because, as is a common complaint in the other reviews I’ve read, the bottle arrived with some leakage. Not a huge amount, but when you’re charging $100 for a small bottle of *anything* it’s completely unacceptable for it to be packaged insecurely enough to lose a single drop. Get it together, guys.

Unassuming Packaging With an Amazing Formulation

In the MD Factor Vitamin C serum, I was blown away by this serum's instant results upon the first application. Before trying this product, I had tried other vitamin C products from the ordinary with minor results, but the formulation of this product seems to be unique. The one major drawback to this product, at least for my skin, is the oiliness. Having Combination oily acne-prone skin, the serum could compound on top of my natural oils leading to an oily mess. To combat this serum's oiliness, I apply a mattifying moisturizer that somewhat cancels out the oiliness of this product. I think the oiliness wouldn't be as much of an issue for mature skin or dry skin. The bottom line, I think this is a great formulation of a vitamin C serum. It instantly brightens and reduces redness on the skin.

High quality vitamin c serum

I’ve used quite a lot of Vitamin C serums in my day. As I know the natural anti-aging benefits of vitamin c. I would say the MD Factor Vitamin C serum is a tad bit oiler compared to ones I’ve used before which I don’t mind at all. I actually quite like this texture and thickness of this serum. I feel it keeps my face moisturized longer. I would recommend this splurge item.

A great serum.

MD Factor’s Vitamin C serum comes in a small glass bottle with a screw off glass dropper. The serum is clear and has no fragrance, unlike some other vitamin C serums that smells like citrus. The serum is fairly thick and applies to my skin well. It leaves my skin feeling a bit oily and nicely moisturizing. A little bit of the serum goes a long way. I use the serum nightly under my night lotion. It makes my skin glow and seems to reduce spots and fine lines. I have noticed no issues with skin irritation or rashes. All in all... great serum.

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MD® SKIN

MD® Vitamin C Serum

Why MD® Vitamin C Serum

MD® Ultimate Vitamin C: The 20% L-Ascorbic Clinical Standard

How to apply MD® Vitamin C Serum

Phase 0: The Signs of Environmental Stress

Phase 1: The Glow of Restored Health

Why the 30-Day Window Matters

Clinical-Strength Vitamin C, Engineered Without the Oxidation

User Proven Results

Key Ingredients: The MD^® Clinical Matrix

How to Use

Complete Your MD® Protocol

Our customers' most-coveted products.

Customer Proven:

Real Results from MD Lash,MD Hair,MD Wellness

Clinical and User Trials

Customer Reviews

Reviews in Other Languages

La Canada Ventures, Inc. · NMSDC Certified MBE · WBENC Certified WBE · Veteran-Owned Small Business · U.S. Federal Contractor (SAM.gov GHQRVKN8GEG7) · GMP & FDA-Registered Manufacturing

Your Cart

MD® SKIN

MD® Vitamin C Serum

Why MD® Vitamin C Serum

MD® Ultimate Vitamin C: The 20% L-Ascorbic Clinical Standard

How to apply MD® Vitamin C Serum

Phase 0: The Signs of Environmental Stress

Phase 1: The Glow of Restored Health

Why the 30-Day Window Matters

Clinical-Strength Vitamin C, Engineered Without the Oxidation

User Proven Results

Key Ingredients: The MD® Clinical Matrix

How to Use

Complete Your MD® Protocol

Our customers' most-coveted products.

Customer Proven:

Real Results from MD Lash,MD Hair,MD Wellness

Clinical and User Trials

Subscribe & Save

Customer Reviews

Reviews in Other Languages

La Canada Ventures, Inc. · NMSDC Certified MBE · WBENC Certified WBE · Veteran-Owned Small Business · U.S. Federal Contractor (SAM.gov GHQRVKN8GEG7) · GMP & FDA-Registered Manufacturing

Your Cart

Key Ingredients: The MD^® Clinical Matrix