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Serum Facial AH-2

Serum Facial AH-2

Product Description

Product overview

Made in Various INTERNATIONAL

A lightweight, fast-absorbing hydrating serum featuring 2% Multi-Weight Hyaluronic Acid Complex (4 types) + 1% Vitamin B5 (Panthenol) to deliver deep, multi-layer hydration that plumps, firms, and adds radiance to all skin types. Clinically proven to increase hydration by 155%.

Cruelty-Free Vegan Fragrance-Free Paraben-Free Silicone-Free Fungal Acne Safe Non-Comedogenic Dermatologically Tested ANVISA Registered
Pregnancy
Consult Doctor
Fungal Acne
Yes
Comedogenic
0/5
Key Active
2% HA Complex
Vitamin B5
1% Panthenol
Size
30ml / 1 fl oz
pH Level
Neutral
HA Types
4 Molecular Weights
Real reviews · YouTube Shorts
Why it's different

Multi-Depth Hydration

4 types of Hyaluronic Acid with different molecular weights penetrate multiple skin layers for comprehensive hydration from surface to deeper epidermis.

01

Texture & feel

SENSORY
Consistency
Lightweight Gel-Serum
Scent
Fragrance-Free
Absorption
Fast (30-60 sec)
Finish
Dewy, Non-Sticky

Multi-Depth Hydration

4 types of Hyaluronic Acid with different molecular weights penetrate multiple skin layers for comprehensive hydration from surface to deeper epidermis.

Clinically Proven Results

155% increase in hydration and 45% reduction in transepidermal water loss demonstrated in clinical studies after 30 days of use.

Barrier Support

Vitamin B5 (Panthenol) provides anti-inflammatory benefits while strengthening the skin barrier and enhancing moisture retention.

Anti-Aging Benefits

Improves firmness by 90% and elasticity by 97% per cutometry studies. Softens fine lines by plumping dehydrated skin.

02

Safety & compatibility

SAFE
Pregnancy & Breastfeeding

Consult your doctor before use. While ingredients are generally considered safe, the brand recommends medical consultation during pregnancy.

Fungal Acne (Malassezia) Safe

Formula is free of fatty acids, ferments, esters, and polysorbates that feed malassezia yeast. Safe for fungal acne-prone skin.

Non-Comedogenic Tested

Clinical comedogenicity study confirmed this serum does not cause blackheads or clogged pores. Rating: 0/5.

Sensitive Skin Approved

Passed primary, accumulated irritability, and skin sensitization tests. Zero participants experienced irritation. Hypoallergenic formula.

Eye Area Safe

Tested and proven safe for use around the delicate eye area. Helps reduce dark circles and under-eye bags.

Compatible with Most Actives

Safe to use with retinol, vitamin C, AHAs, BHAs, niacinamide, and peptides. No significant restrictions with other skincare actives.

03

Ingredient breakdown

INGREDIENTS

Sodium Hyaluronate (High MW) Part of 2%Proven

High molecular weight hyaluronic acid that forms a moisture-retaining film on the skin's surface, providing immediate hydration and plumping effects while preventing transepidermal water loss.

  • Function: Surface hydration, film-forming, immediate plumping
  • Evidence: Extensively studied humectant that can hold up to 1000x its weight in water

Sodium Hyaluronate Crosspolymer Part of 2%Advanced

A modified, crosslinked form of hyaluronic acid that stays on the skin longer than regular HA, providing extended hydration benefits and improved stability.

  • Function: Extended-release hydration, longer-lasting moisture
  • Evidence: Studies show improved moisture retention compared to standard HA

Sodium Acetylated Hyaluronate Part of 2%Premium

Acetylated form of HA with enhanced penetration abilities. The acetyl group acts as an "anchor" that binds more effectively to skin, providing deeper and longer-lasting hydration.

  • Function: Deep penetration, enhanced binding to skin
  • Evidence: 2x better moisture retention than standard HA in studies

Hydrolyzed Sodium Hyaluronate Part of 2%Proven

Ultra-low molecular weight (mini) hyaluronic acid that penetrates deeper into the epidermis, providing hydration at the lower skin layers where it supports collagen synthesis.

  • Function: Deep layer hydration, supports skin structure
  • Evidence: Penetrates to deeper epidermis layers per molecular size studies

Panthenol (Vitamin B5) 1%Proven

Pro-vitamin B5 that deeply penetrates skin, converting to pantothenic acid. Known for its moisturizing, anti-inflammatory, and wound-healing properties. Strengthens skin barrier.

  • Function: Humectant, anti-inflammatory, barrier repair
  • Evidence: Multiple studies confirm wound healing and barrier support benefits
Comedogenic rating: 0 - Will not clog pores

Glycerin SupportingProven

A powerful humectant naturally found in skin. Studies show it may be more effective than hyaluronic acid at drawing moisture. Softens and smooths skin texture.

  • Function: Humectant, skin softening, barrier support
  • Evidence: 2016 study found glycerin more effective than AHAs and HA as humectant

13 ingredients

Aqua (Water), Sodium Hyaluronate, Pentylene Glycol, Propanediol, Sodium Hyaluronate Crosspolymer, Panthenol, Glycerin, Ahnfeltia Concinna Extract, Sodium Acetylated Hyaluronate, Hydrolyzed Sodium Hyaluronate, Sodium Gluconate, Ethylhexylglycerin, Phenoxyethanol

FREE FROM: Parabens, Petrolatum, Silicones, Fragrances, Dyes/Colorants, Gluten, Sulfates, Mineral Oil, Phthalates, Formaldehyde, Animal-Derived Ingredients
04

Where it fits in your routine

ROUTINE
1
Cleanser
2
Toner
3
HA Serum (This Product)
4
Treatment Serum
5
Moisturizer
6
Sunscreen (AM)

Apply on clean, dry skin before heavier products. Can be used both AM & PM. Layer under treatment serums, moisturizers, and sunscreen.

05

How to use

HOW TO USE
1

Cleanse Your Face

Start with clean, dry skin. Pat face dry after cleansing - do not leave skin damp.

2

Dispense 3-4 Drops

Without touching the dropper to skin, dispense a few drops onto fingertips or directly onto face.

3

Apply Gently

Spread evenly across face, including the eye area. Use gentle patting motions to help absorption.

4

Follow with Moisturizer

Always seal with a moisturizer to lock in hydration. In AM, finish with sunscreen.

06

Who is it for?

WHO

Perfect for you if:

  • You have dehydrated skin that needs a moisture boost
  • You want to plump fine lines caused by dryness
  • You need a lightweight hydrator for oily/combination skin
  • You have fungal acne and need a safe hydrating serum
  • You want affordable, clinically-tested skincare
  • You prefer fragrance-free, minimal ingredient formulas
  • You need a hydrating serum safe for the eye area

Consider alternatives if:

  • You have very dry skin and need richer emollients
  • You want anti-aging actives like retinol or peptides
  • You prefer thicker, more occlusive textures
  • You're looking for brightening or exfoliating benefits
  • You want a single product that does everything
07

Skin type compatibility

SKIN TYPES
Oily Skin
Excellent

Lightweight gel texture absorbs quickly without adding shine or greasiness. Perfect for oily skin that still needs hydration.

Dry Skin
Good

Provides excellent hydration but may need a richer moisturizer or facial oil on top for very dry skin types.

Combination Skin
Excellent

Balances well across all zones. Hydrates dry areas without overwhelming oily T-zone. Ideal texture for combination skin.

Sensitive Skin
Excellent

Fragrance-free, hypoallergenic formula tested for irritation. Zero participants experienced sensitivity in clinical trials.

Acne-Prone Skin
Excellent

Non-comedogenic and non-acnegenic tested. Fungal acne safe. Brand states it may actually benefit acne-prone skin.

Mature Skin
Good

Helps plump fine lines via hydration and improves elasticity. Best paired with anti-aging actives like retinol for mature skin.

08

Results timeline

30+ DAYS
Immediately

Instant Hydration Boost

Skin feels immediately hydrated and plumped. Lightweight, non-sticky finish absorbs within 30-60 seconds.

100% noticed
1 Hour

Measurable Hydration Increase

Corneometry studies show 40% increase in skin hydration levels within just one hour of application.

40% hydration increase
Week 2

Improved Skin Texture

Continued hydration leads to smoother, softer skin. 15-day corneometry shows sustained 40% hydration improvement.

100% noticed softness
Week 4

Visible Firmness & Radiance

Clinical studies show 125% improvement in softness/hydration, 97% in elasticity, and 23% in firmness. Fine lines appear reduced.

90% noticed firmness
30+ Days

Complete Transformation

155% total hydration increase. 45% reduction in water loss. 85% noticed improvement in wrinkles and fine lines.

85% noticed wrinkle reduction
09

Ratings by platform

726+ REVIEWS
Principia Official
4.9
Rating
226+
Reviews
Main feedback: Some users with very dry skin need additional moisturizer on top
Amazon Brazil
4.7
Rating
500+
Reviews
Main complaint: Small bottle size (30ml) runs out quickly with twice-daily use
SkinSort
#1
Top Rated
Principia
Best Serum
Note: Rated the top Principia serum on SkinSort for ingredient quality and safety
Guia do Skincare
4.0
Rating
Expert
Review
Expert note: Excellent hydration; anti-aging claims may be overstated for hydration-only benefits
10

Pros & cons

BALANCED

Praised

  • Excellent multi-depth hydration with 4 HA types
  • Lightweight, fast-absorbing, non-sticky texture
  • Clinically proven results (155% hydration increase)
  • Fungal acne safe and non-comedogenic
  • Safe for sensitive skin and eye area
  • Clean formula - no parabens, fragrance, silicones
  • Very affordable price point (~$10-11 USD)
  • Cruelty-free and vegan
  • Works well under makeup and sunscreen

Criticized

  • Small 30ml bottle runs out quickly
  • May need additional moisturizer for very dry skin
  • Anti-aging claims may overstate hydration-only benefits
  • Limited international availability
  • Some users report pilling with certain sunscreens
  • No additional actives (purely hydrating)
11

Budget-friendly alternatives (dupes)

DUPES
90% Match
Hyaluronic Acid 2% + B5 Serum
$8.90
Budget Pick

Very similar formula with 2% HA complex and vitamin B5. Original version has 4 HA types like Principia. Globally available. Slightly thicker texture.

85% Match
The Ordinary HA 2% + B5 with Ceramides (New)
$9.90
Budget Pick

Updated formula with 5 types of HA plus ceramides for added barrier support. Lighter texture than original. Contains Polysorbate 20 (check for FA safety).

75% Match
Hyalu B5 Eyes Serum
$35.00

Contains 2 types of HA + vitamin B5 + madecassoside. Richer texture, includes fragrance. Added soothing benefits from thermal water. Not fungal acne safe.

70% Match
Hyaluronic Acid Hydra Power Essence
$15.00
Similar Price

K-beauty option with sodium hyaluronate. Lighter essence texture. Contains niacinamide for added benefits. May not be fungal acne safe - check ingredients.

12

Comparison with competitors

SIDE-BY-SIDE
Pycnogenol 5%
HA Types 4 Molecular Weights
Vitamin B5 Yes (Panthenol)
Size 30ml
Fungal Acne Safe Yes
Fragrance None
Clinical Studies Limited
Hyalu B5 Cream
HA Types 2 Molecular Weights
Vitamin B5 Yes (Panthenol)
Size 30ml
Fungal Acne Safe No
Fragrance Yes (Added)
Clinical Studies Yes
Minéral 89 Hyaluronic Acid Booster
HA Types 1 Type
Vitamin B5 No
Size 50ml
Fungal Acne Safe No
Fragrance Yes (Added)
Clinical Studies Yes
13

Storage & shelf life

36 MONTHS
Period After Opening (PAO)

36 months (3 years) from date of manufacture. Check packaging for specific expiration date.

Storage

Store in a cool, dry place away from direct sunlight. No refrigeration required.

Packaging

Glass dropper bottle with pipette applicator. Hygienic dispensing without product contamination.

Travel Friendly

Yes, 30ml is under the 100ml TSA liquid limit. Compact glass bottle fits easily in toiletry bags.

13

Frequently asked questions

FAQ

The brand recommends consulting your doctor before use during pregnancy. While the ingredients (hyaluronic acid, panthenol, glycerin) are generally considered safe and don't contain any known pregnancy-unsafe actives like retinoids or salicylic acid, medical consultation is advised out of caution. The formula is free from the most concerning pregnancy-unsafe ingredients.

Yes! This serum is fungal acne safe. The formula is free from fatty acids, fermented ingredients, esters, polysorbates, and oils that can feed malassezia yeast. SkinSort rates Principia serums as fungal acne safe. It's an excellent hydrating option for those dealing with fungal acne.

Yes! According to Principia, there are practically no restrictions for combining this serum with other actives. Hyaluronic acid is a hydrating ingredient that pairs well with retinol (helps buffer dryness), vitamin C (apply HA after), AHAs, BHAs, and niacinamide. Apply the HA serum before treatment serums or after water-based treatments, before oils and creams.

This serum works for ALL skin types. It's particularly excellent for oily, combination, sensitive, and acne-prone skin due to its lightweight, non-comedogenic formula. Dry skin types will benefit from the hydration but may need a richer moisturizer on top. Clinical testing confirms it's safe for all skin types and the eye area.

Hydration effects are immediate - you'll feel plumper, softer skin right away. Clinical studies show 40% hydration increase within 1 hour. After 15-30 days, you'll see 155% hydration improvement, 90% firmness improvement, and 85% reduction in fine lines. Best results come with consistent twice-daily use for at least 4 weeks.

Apply after cleansing and toning, on clean, dry skin. This serum should go BEFORE treatment serums (like vitamin C, retinol), moisturizers, and sunscreen. General rule: thinnest to thickest consistency. Use both morning and night for best results.

No! This serum underwent clinical comedogenicity and acnegenicity testing and showed NO comedogenic or acnegenic effects. Comedogenic rating: 0/5. The brand states it may actually benefit acne-prone skin. All ingredients have low comedogenic ratings - panthenol and glycerin are both rated 0.

The product has a 3-year shelf life from the date of manufacture. Once opened, it should be used within a reasonable timeframe (typically 12 months for serums). The 30ml bottle typically lasts 1-2 months with twice-daily use. Store in a cool, dry place away from direct sunlight.

— Skincarisma verdict
4.6 / 5 ★★★★★

Verdict: Principia AH-2 is an outstanding value in the hyaluronic acid serum category. With 4 types of HA at different molecular weights plus vitamin B5, it delivers clinically-proven multi-layer hydration that rivals products 3x its price. The clean, fungal-acne-safe, fragrance-free formula makes it suitable for virtually everyone, including sensitive and acne-prone skin. While the small 30ml size and limited international availability are drawbacks, the impressive clinical results (155% hydration increase, 97% elasticity improvement) and budget-friendly price make this Brazilian gem a top pick for anyone seeking serious hydration without irritation. An excellent choice as a standalone hydrator or to layer under your treatment serums.

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Product Overview

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Quick product notes are a great way to check if a product is free from commonly avoided ingredients by skincare enthusiasts. These preferences come about for different reasons depending on the ingredient such as personal experiences, sensitivities, health preferences & etc.

muscle Pro Tip Alert!

Just because a product is not free from a common preference does not mean it's a bad product! You can make a personal decision whether or not you want to use a product that contains these ingredients or not - click the labels of the preference to read more about them.

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Quick Product Notes

Click on icons for more information
question
lightbulb What are Notable Effects & Ingredients?

Ever used a product that promised a certain effect but provided no results? It might not have contained any notable ingredients that could have been responsible for that promised effect. It doesn't matter what the marketing or packaging «promises» it can do, if it doesn't contain anything that can help - then the likelihood of it helping is low.

We help you identify key notable ingredients that have been shown to help with effects such as acne-fighting, brightening, UV-protection, wound healing & anti-aging to help you achieve your skincare goals smarter. Please note that different notable ingredients have varying levels of research behind them, some are extremely well proven yet some have mixed research in their efficacy.

muscle Pro Tip Alert!

Just because a product doesn't contain any notable ingredients doesn't mean it's bad. And a product with notable ingredients (or even many) doesn't necessarily guarantee the efficacy of the product performing these effects either. There are other factors such as ingredient quality, concentration and formulation that will ultimately determine this.

Be smart and use this as just a starting point for you to make more informed and smarter choices and compare it with reviews to see if the product is right for you

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Notable Effects & Ingredients

brightening Brightening from 1 ingredient(s):
Glycerin
wound Promotes Wound Healing from 4 ingredient(s):
Sodium Hyaluronate Hydrolyzed Sodium Hyaluronate Glycerin Panthenol
question
lightbulb What are Ingredients Related to Skin Type?

Why are some products great for some people and horrible for others? Well everyone has different skin types and different reactions to the same ingredients.

We've identified a range of ingredients that are commonly regarded as potentially good or bad for those with Dry, Oily/Acne-Prone or Sensitive skin.

muscle Pro Tip Alert!

A product that contains good or bad ingredients for your skin type doesn't always flat out make the entire product good or bad for your skin. There are other factors such as ingredient quality, concentration and formulation that will ultimately determine your skins reaction.

One of the best ways to use this section is to troubleshoot products you've had bad experiences with in the past. Check if it contains any of the marked ingredients to point out suspect ingredients to avoid in the future!

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Ingredients Related to Skin Types

Click on icons for more information
dry-skin Dry Skin
3
oily-skin Oily/Acne-Prone Skin
sensitive-skin Sensitive Skin
question
lightbulb What is the Ingredient Safety Breakdown?

Ingredient Safety Breakdown refers to the percentage % of ingredients in different risk categories as classified by EWG (Environment Working Group) if they are available. There are almost endless cosmetic ingredients and they are one of the few organisations globally that have assigned ratings to a lot of the more commonly used ingredients which is why we reference them.

muscle Pro Tip Alert!

EWG is seen by many to be more on the alarmist side in their assignment of health ratings resulting in rating ingredients as riskier than they actually are. We recommend using this a reference point rather than a strict guide of ingredient safety and to always do further research if into ingredients that you may find suspect.

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Ingredient Safety Breakdown

EWG Health Ratings
Low risk
Medium risk
High risk
Unknown risk
76% 15% 7%

Product ingredient list

Showing first 5 of 13 ingredients
EWG CIR Ingredient Name & Cosmetic Functions Notes
1 Unknown
Water
Solvent, Skin Conditioning
1 Unknown
Sodium Hyaluronate Crosspolymer
Skin Conditioning, Humectant
1 A
Pentylene Glycol
Solvent, Skin Conditioning
1 A
Sodium Hyaluronate
Skin Conditioning, Humectant
Promotes Wound Healing
Hydrating
1 Unknown
Sodium Acetylated Hyaluronate
Humectant
VIEW ALL INGREDIENTS