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Si-Nails Nail Strengthener
Is this right for my skin?
Not sure if this product is right for your Baumann Skin Type®? Take the quiz to find out and get up to 20% off your custom routine.
Take the quiz Finish the quizRight for your skin type
Nothing in this product works against any of your four letters, so it is safe for your skin type.
Not recommended for your sensitivity
If your nails are weakened by psoriasis, illness, or medications like chemotherapy, our nail care collection offers solutions.
- Formaldehyde and Toluene Free
- Helps nails grow longer
- Strengthens nails
Authorized retailer
We hold a direct account with ISDIN. Every unit is authentic, in date, and stored properly.
Free shipping over $49 · easy returns
Ships in 1 to 2 business days. 30 days to return anything unopened.
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Approved for Baumann Skin Types
- 1
- 2
- 3
- 4
- 5
- 6
- 7
- 8
- 9
- 10
- 11
- 12
- 13
- 14
- 15
- 16
Approved for all 16 Baumann Skin Types. Dr. Baumann reviews every product against all 16 types before it goes on the site.
Fragrance Free
Oxybenzone Free
Dye Free
Gluten Free
Phthalate Free
Formaldehyde Free and FRA Free
What it is and what it does
ISDIN Si-Nail Strengthener is an innovative nail growth treatment, clinically proven to strengthen brittle nails by increasing their thickness, density, and durability. In just 14 days, you'll notice visible improvements in nail strength and overall quality. After 28 days, 97% of users reported harder, faster-growing nails. This nail polish-friendly formula is fragrance-free, and free from toluene and formaldehyde, making it safe for regular use.
Key ingredients include Silanediol Salicylate, which promotes silicon, a key mineral for nail health, and Pistacia Lentiscus Gum, which encourages keratin production—essential for strong, healthy nails. Additionally, the inclusion of Cationic Hyaluronic Acid enhances cuticle moisture and repairs brittle nails, reducing roughness and boosting overall nail durability.
Who it is for
- Formaldehyde and Toluene Free
- Helps nails grow longer
- Strengthens nails
Approved for all 16 Baumann Skin Types.
Key ingredients
Caprylic/Capric Triglyceride
Combination of hydrating coconut oil and glycerin to moisturize skin.
Full ingredient list
Product type and skin type data
| Brand | ISDIN |
|---|---|
| Product type | Textiles |
| Size | 2.5 mL |
| Item number | ISD-74153 |
| Approved Baumann Skin Types | ORPT, ORNT, ORPW, ORNW, DRPT, DRNT, DRPW, DRNW, DSPT, DSNT, DSPW, DSNW, OSPT, OSNT, OSPW, OSNW |
| Recommended for these sensitivities | Acne, Redness, Stinging |
Frequently bought together
Dr. Baumann pairs these together.
Questions about this product
Answered by Dr. Leslie Baumann, MD, FAAD · Miami, FL · 200+ partner practices
Visible improvements typically begin in 14 days, but for
best results, ongoing application is recommended. Most users report stronger,
thicker nails after 2-4 weeks of consistent use.
No, ISDIN Si-Nails needs to be applied directly onto bare
nails daily. It's best to avoid nail polish during treatment to maximize the
product’s effectiveness.
Apply the product daily to clean, dry nails. Consistent
daily application is key to seeing visible improvements in nail strength and
growth.
ISDIN Si-Nails is unique because it boosts nail thickness
and density while also hydrating the cuticle. Unlike many strengtheners, it
promotes overall nail health and growth in as little as 14 days.
Reviews
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