Fast-absorbing serum nail strengthener


ISDIN Si-Nails is an innovative nail growth formula that has been clinically proven to strengthen brittle nails by increasing thickness, density, and durability of the nail and cuticle. Visible results in just 14 days.

2.5 mL

Fragrance free, fast-absorbing, invisible finish

Brittle nails

Silanediol salicylate, pistacia lentiscus gum, cationic hyaluronic acid

Improves nail hardness and flexibility
Si-Nails is a fast-absorbing serum nail strengthener which uses a unique combination of effective ingredients to promote healthy, strong nails.
Increases nail strength and durability while helping to repair brittle nails and reduce roughness.
Promotes keratin and silicon in the nails to help improve growth, and overall quality.
Hydrates the nails and cuticles, moisturizing the entire nail structure to keep nails supple and flexible.
Efficacy on brittle nails after 14 days¹
Si-Nails helps strengthen nails and give a healthier appearance after just 14 days of daily use.¹ Image shown corresponds to 28 days of use.


After just 28 days of use¹, consumers reported their nails were:
Harder & grew faster
Less brittle
More attractive
¹Data on file. ISDIN Corp. 2023. Morristown, NJ.


Expert formulations for optimal nail health
Silanediol salicylate
Promotes silicon, which is one of the predominant minerals in the nail.
Pistacia lentiscus gum
Promotes keratin, an essential component to strong and healthy nails.
Cationic hyaluronic acid
An enhanced version of one of the most well known moisturizers in the world, which promotes cuticle moisturization.

How to use

Daily care for damaged nails
Si-Nails nail strengthener is a clear, lightweight serum delivered by an easy-to-use, one-click applicator pen, applied once a day. It can be applied to nails with colored nail polish. The first time you use Si-Nails, activate the brush by pressing down on the applicator until the brush is moistened (approximately 25 times). After first use, just click once for each nail you would like to apply it to. Visible results may be seen in 14 days, with best results achieved from ongoing application.
Step 1
Click and apply nail repair serum to the nail and cuticle, covering the nail edges
Step 2
Apply in vertical strokes across the entire nail surface.
Step 3
Apply underneath nail. Click to repeat Steps 1-3 for each nail Si-Nails is applied to.

Doctor tip

Dr. Bianca Maria Piraccini
Director of European Nail Institute
“ISDIN Si-Nails is specially designed to be both effective and easy-to-use and it can represent one of the first choices of treatment in patients with nail brittleness and tendency to breakage.”
“ISDIN Si-Nails is specially designed to be both effective and easy-to-use and it can represent one of the first choices of treatment in patients with nail brittleness and tendency to breakage.”


Can I use Si-Nails on top of nail polish or gel?
Yes! Si-Nails can be applied on top of colored nail polish or gel.
How long do I need to use Si-Nails for?
Results can be seen from as little as 14 days. However, it depends on the condition of your nails before starting Si-Nails nail strengthening treatment. The condition of your nails will improve with extended use.
The first time I used Si-Nails, I didn’t see any product come out. How do I start using it correctly?
Before using Si-Nails for the first time, activate the click pen by pressing down on the click button at least 25 times, until the applicator is moistened. This will activate the flow and you will be able to start using Si-Nails correctly from then on. You only need to click 25 times at first application.




Fast-absorbing serum nail strengthener