Brief Answer:
Trimming and application of moisturizers help

Detailed Answer:
Dear Madam.Thanks for giving me an opportunity to address your query.

I have a few suggestions/precautions to minimize finger nail splitting-

1.Reduce the frequency of wetting your nails.
2.In case you don't wet your nails often then dehydration might be the cause.Soak the nails in water daily, 15 minutes at a time, to increase the water content (hydration) of the nails.
3.Trim the nails short to reduce worsening of the nail splitting.
4.Protect your nails by wearing plastic or rubber gloves over thin cotton gloves while doing all housework, including food preparation.
5.Apply moisturizers (emollients), such as petroleum jelly or Cetaphil, to improve nail hydration.
6.Apply nail-hardening agents containing formaldehyde to increase nail strength. But they should be used cautiously, as they can cause brittleness and other nail problems. Apply these hardeners only to the free edge (growing end) of the nail.

I would be glad to know if you have any history of nail/skin disease(like psoriasis)?
Do you take any medications like Vitamin A etc?

Hope this answers your query.

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