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Thick Toenails: Trimming, Treatment & Causes

Reviewed by
Dr. Joseph DAmico

Our toenails thicken and harden naturally as we grow older, but this can occur at any age. When toenail thickening occurs in younger people it is most commonly due to infection or injury.

If the thickening is caused by toenail fungus, the nail may turn a yellow or brown color before it begins to thicken. Fungal infections often have a foul odor, and may cause fluid to collect under the nail

While major trauma to the nail is an obvious cause of thickening, it is more often the result of repetitive pressure on the nail during everyday activities. The continual striking of the nail against the shoe causes it to separate from the nail bed.

Certainly we expect to see this in long-distance runners or soccer players, but ordinary walkers are just as susceptible. The likelihood of this occurring is multiplied when mileage is increased, sneakers are too short, or walking routes with steep inclines alter the biomechanics of everyday motion.

Thickened toenails can be painful and difficult to cut, and they can increase one’s susceptibility to infection.

thick toenails

What Causes Toenails to Thicken?

  • Any alteration to the nail plate, nail bed, or root of the nail can result in thickening. This damage may be temporary or permanent, depending on the cause.
  • We can add thickened toenails to the list of changes that occur with age. While it may be simply the accumulation of trauma over time, other factors such as metabolic change and the reduction of blood flow also play a role.
  • As previously mentioned, fungal infections are a major cause of thickening toenails, but bacterial infections, which often accompany ingrown toenails, may have the same effect.
  • Trauma, whether caused by he dropping of a hammer on the toe or by the imperceptible pressure of a shoe, can result in permanent thickening of the nail.
  • Systemic diseases such as psoriasis, eczema, rheumatoid arthritis, cardiovascular disease, and cancer, to name a few, may affect the toenails.

Is There Hope for Thickened Toenails?

Absolutely! Careful filing and trimming with a nail file or emery board can reduce the thickness of a toenail. If you are unsure how to go about grooming yourself, you should talk with your podiatrist or doctor about specific techniques.

Your doctor will be able to show you the proper way to groom your nails to reduce their thickness and prevent them from re-thickening.

Treatment of thickened toenails depends on the cause of the problem. If the thickening is due to a fungal infection, topical or oral anti-fungal medicines may be prescribed. Lasers designed specifically for eradicating fungi have also recently become available.

The procedure is painless, fast, and reported to be 85 percent effective. Regardless of what type of treatment is used, however, anti-fungal agents must still be used to prevent recurrence once the infection is cleared.

If the thickening is due to injury or age, your doctor may first employ conservative treatments, such as reducing the size of the nail plate. In cases where the thickened nail is chronically painful, removal of the nail down to the root may be necessary.

Should the cause be systemic, the underlying disease must be diagnosed and treated before the nail problem can be addressed.

How to Trim Thick Toenails

Trimming thickened toenails is a much more difficult task than trimming normal nails. In most cases your nail trimmer will be ineffective, and you may need a nail file or emery board and podiatry-grade nippers.

Consulting your podiatrist or primary care physician is recommended, especially for individuals with diabetes, poor circulation, or reduced sensation, or those taking anti-coagulants such as Warfarin, Coumadin, or Plavix.

The following is the recommended way to trim thick toenails:

  • Soak your nails for at least ten minutes in warm, soapy water.
  • Completely dry your toenails.
  • Use the emery board or file.
  • Trim the nails, starting at one corner and continuing straight across to the other corner. Smaller cuts with the trimmer will prevent splitting or chipping.
  • One important note: do not use cuticle pushers, which disturb the natural barrier that prevents the introduction of potential pathogens.

Preventing Thick Toenails – It’s Possible!

Here are some tips to help you prevent toenail problems:

  • Always watch for changes in the skin and nails. Such changes may indicate an underlying problem that should be checked by your podiatrist.
  • Trim your nails straight across, and not too short.
  • File your nails regularly in order to prevent sharp edges.
  • Wear properly-fitting shoes and socks with adequate space for toes and nails.
  • Keep your shoelaces tied tightly to prevent the foot from sliding in the shoe.
  • Avoid shoes with small toe boxes or high heels.
  • If you’re having difficulty (for example, if you’re cutting flesh), seek help from a professional.

Questions to Ask Your Doctor

Here are some questions you may wish to ask your doctor about thickened toenails:

  • What should I do if preventive measures aren’t effective and the nails continue to thicken?
  • What caused my toenails to thicken?
  • Do the activities I participate in affect my toenails?
  • Will my toenails return to normal?
  • What treatment option is best for me?
  • Do my shoes fit properly?

Helpful information from other websites:

Medical References:

  1. M. Beers "Merck Manual of Medical Information" 2nd home edition (Pocket Books, 2003) 410
  2. American Medical Association "Family Medical Guide" 4th Edition (John Wiley & Sons, Inc. 2004) 1078
  3. Taber's Cyclopedic Medical Dictionary, 21st edition (F.A. Davis Company, 2005) 1631

This page was last updated on October 2nd, 2015

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