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ISDIN Si-Nails - Fast Absorbing Nail Strengthening and Hardening Serum for Nail Durability in Thin Nails, made with Cationic Hyaluronic Acid 0.08 FL OZ

  • Based on 2,173 reviews
Condition: New
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Availability: In Stock.
Fulfilled by Amazon

Arrives Sunday, May 18
Order within 6 hours and 23 minutes
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Brand: ISDIN


Item Form: Gel


Specialty: Strengthener


Number of Items: 1


Unit Count: 1 Count


Is Discontinued By Manufacturer ‏ : ‎ No


Product Dimensions ‏ : ‎ 1.61 x 1.14 x 5.67 inches; 0.32 ounces


Country of Origin ‏ : ‎ Spain


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Sunday, May 18

This item is non-returnable:

Non-returnable. Transportation of this item is subject to hazardous materials regulation

View our full returns policy here.

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Leasing options through Acima may also be available during checkout.

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Top Amazon Reviews


  • It Works!!!!
It works! I've tried so many products that were "supposed" to strengthen my nails so I was skeptical. I went to a new nail salon and they drilled my already thin nails into nothing. My nail beds were tender for 2 weeks. I was looking for ANYTHING that might help. I read the reviews and decided to give it a try. After the first week, I noticed my nails were definitely stronger. I've been using for 2 weeks now and I've been amazed. This stuff is the real deal! ... show more
Reviewed in the United States on April 11, 2025 by Kindle Customer

  • Effective in repairing thin, splitting nails
I used this every day on my nails for 2 months. That's how long it lasts - not long - but in that time, it really helped my nails, which were thin, splitting, and breaking constantly. Part of the reason for the poor condition of my nails is simply age when nails tend to thin, but I also had been using nail polish and nail polish remover regularly. I gave my nails a rest from all of that while I used this product and they began to grow back in much better condition. I think that to really transform your nails, it would help to use this product until the old nail completely grows out. It is expensive, which is a minus, and there isn't much product, but it is very effective. ... show more
Reviewed in the United States on July 25, 2024 by donatella

  • Dried my nails out worse
I have spent hundreds of dollars trying to fix my nails. Over the last year they have become super thin and they peel like crazy. I don't do polish or fake nails that would damage them. I'm on all kinds of hair skin nails supplements. I've tried moisturizers, repairs treatments, strengtheners, hardeners. Nothing is working. And this product actually dried my nails out even more. Super bummed for how much I spent on it. What a waste. ... show more
Reviewed in the United States on May 11, 2025 by Tawni S

  • Really works!
I’ve been using this off and on for about 2 months and have noticed a difference on my brittle, peeling nails. I’ve tried dozens of different products and nothing else has helped. I’ve put this on my bare nails 3-4 times a week at night (when I wasn’t wearing nail polish) and it has drastically reduced the peeling and cracking that has taken over my nails as I’ve gotten older. It is pretty expensive but I’m on the same tube 2 months later so it’s definitely worth a try! ... show more
Reviewed in the United States on March 29, 2025 by AP

  • A Miracle
I have waited four months to write this review because it just seemed too good to be true. But it is true. I am a senior citizen who suddenly found all my nails chipping, cracking, and splitting. I thought about posting a "before" picture, but they looked too awful. I used to try to hide my hands when in public. I tried nine months of biotin capsules, and no results. I found a recommendation from other users online of the ISDN product. When I started using it, I was completely skeptical. The product is clear, thin, and more like water than anything else. I could not see how this could work. It took six to eight weeks before I began to see genuine results - tiny 1/8" nails taking the place of nails that looked like they had been chewed off by rats. Now, five months on, I have 1/4" normal-looking nails that make me happy every day. I have to file them to keep from getting too long, but not in order to even out breakage. They don't seem to chip or break at all under normal use. I actually took the ISDIN box to show my doctor. She said they often have people ask for help with breaking nails, and they never have anything to suggest. She took down the info about this product. For me, a container lasts about two months or longer. I have noticed that the applicator doesn't always work the way the instructions say. Often I get enough product from one "click" to do a whole hand. Other times, the applicator needs to be primed several times. But I don't care as long as it works SO well. Reading over my review, it looks like someone paid me to write it! It's all true. ... show more
Reviewed in the United States on May 11, 2025 by Amazon Customer

  • Really truly works
Life changing (at least for my nails LOL). I never leave reviews but this is too good not to share. Disclaimer: I'm a nail nut. A few years ago, at the age of 53, I decided I was very tired of brittle, flaky, dry, weak nails. I have always taken care of my nails, so the changes I was seeing were age related. I was eating healthy and exercising, was using nail polish but never gel, I moisturized etc. Nothing was helping. I used a special nail oil 6-8 times a day and no acetone and no nail polish for A YEAR and saw very little improvement. Then I discovered Dr Dana's Deep Hydrading Formula and saw an immediate improvement using their Deep Hydrating Formula...again I applied it on average 6 times a day so definitely was committed. My nails stayed short but stopped splitting and chipping...that was after about a month of use. They also have a hyaluronic serum but recommend using once a week. Then I discovered this product and went nuts with it. I bought three applicators, kept one by my desk, one in my bathroom and one in my car. I probably apply it 12 times a day LOL...certainly after any time I was my hands. It's easy. I apply a top 'coat' of the Dr Dana Formula after using the SI-NAILS. This is the magical combo. My nails are strong, flexible, and growing. This is the best they've looked in 20 years. So if you are unhinged like me and willing to go the distance, the combo of these two products changed my nails, they look 30 years younger ;) ... show more
Reviewed in the United States on April 11, 2025 by GdF GdF

  • did strengthen slightly, but ridges not affected
I used this product daily for 8 weeks. I do believe it has slightly strengthened my nails as I haven't had any split in the past month. However, I was mostly hoping it would make the ridges in my nails less evident, and that has not changed. I will use up what I have (I found one tube lasts me a month), but due to expense will probably not buy any more. ... show more
Reviewed in the United States on March 1, 2025 by Carl J Wold

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