By Vivian Valenty, Ph.D.
A product that claims to remove calluses is a drug, not a cosmetic. Drugs must first obtain U.S. Food and Drug Administration (FDA) approval before being sold on the market. The term “callus remover” is FDA-regulated. FDA-approved drugs will have monographs published in the Code of Federal Registrations (CFR) Title 21.
The final monograph covering corn and callus remover products found in 21 CFR part 358 subpart F states, “only active ingredients that meet monograph conditions are salicylic acid at 12-40% in a plaster vehicle and 12-17.6% in a collodion-like vehicle.” Therefore, a product without salicylic acid present at these concentrations when sold for use as a corn or callus remover is in nonconformance to 21 CFR. It is called misbranded and is prohibited from the market for this use before obtaining FDA approval as a new drug.
The FDA-approved salicylic acid products for callus removing do not provide instant results and require multiple applications for two weeks or more. This procedure does not lend itself to being incorporated into a quick salon pedicure in which the client demands immediate results. Thus, products are called callus softeners, callus erasers, callus eliminators, callus off, callus away, etc., to avoid using the term callus remover. To conform with the final monograph on callus removers, these products claim callus softening instead of callus removing and require the intervention of implements to facilitate the removal of the softened calluses during a single pedicure session.
In a usual pedicure, nail technicians theoretically and practically do both callussoftening and removing because they do not just apply the callus softener and leave it on the client for the product to dissolve or peel the callus at home as with a callus remover.
Callus Softener Types
Caustic. Caustic softeners are usually aqueous gels and contain sodium or potassium hydroxide with a pH over 13.5. These are highly alkaline and should be used with proper personal protection equipment (PPE) to avoid skin injury to nail technicians and their clients. Serious injury results when they contact live skin or accidentally get into the eyes.
Urea. Urea-based softeners are commonly aqueous liquids containing about 20% urea with a pH of 6 to 9.
AHA/BHA. Alpha- and beta-hydroxy acid-based softeners are available in liquid or cream formulations. These products are acidic (pH of about 3 to 4).
Some nail professionals prefer to use alkaline softeners because they dissolve the dead skin cells faster than either urea-based or acid-based softeners. However, due to their safer nature, I recommend urea-based and acid-based softeners. To me, safety is above speed in importance. The acid softeners are safe for clients to use at home for the maintenance of their salon pedicure. By selling these acid softeners to clients with proper instructions to use daily on the heels, the nail professional makes a nice profit on the retail sale. If the client adheres to the prescribed regimen, the nail technician will find it easier and quicker to perform callus reduction during subsequent client’s visits.
The next step of a pedicure service is callus removal, where the nail technician uses a foot file to reduce the thickness of the callus and gently smooth out the newly exposed skin surface. We should call this step callus reduction because some calluses on the heels and soles of feet are necessary.
Calluses are common and develop on our soles to protect the skin against the pressure from supporting our body weight. Calluses on feet are therefore essential, and we should not be removing them completely. However, when allowed to develop unchecked, the hardened thick skin could lead to discomfort and develop cracks, which might harbor pathogenic microorganisms. Calluses should therefore be regularly reduced and smoothed out.
The best foot files are those that have just the right level of abrasiveness (a.k.a. grit) or do not have sharp edges. Therefore, they will not cause injury to the foot by tearing the live skin. They must be seamless stainless steel for best sanitization after each use or disposable for single use.
Step 1. Sanitize the client’s feet.
Step 2. Analyze feet for any open wounds or any abnormalities that may prevent a service from being performed on the client.
Step 3. Remove old nail polish using cotton saturated with polish remover. If the client has naked nails, skip this step.
Step 4. Apply a small bead of cuticle remover to all 10 proximal nail folds. Keep it confined to the cuticle, and do not coat the nail plate with the remover.
Step 5. Spray the soles of the feet with a urea-based callus softener and wrap feet in steamed towels. You may use warm booties. Allow the softener to sit on the soles for three to five minutes.
Step 6. Expose the first foot’s toes, leaving the rest of the foot wrapped to maintain warmth and moisture.
Step 7. Deactivate cuticle remover by spraying with water and thoroughly wash off the first foot.
Step 8. Gently push back cuticles using a pusher. Never push back cuticles with cuticle softener still on the nail plate, as this can cause damage to the natural nail.
Step 9. Perform cuticle grooming.
Step 10. Apply one drop of cuticle oil per foot, and massage into each nail.
Step 11. Expose the toes on the second foot, and repeat steps seven to 10.
Step 12. Unwrap first foot, and spray the sole with urea-based callus softener, including the tips of toes and all calluses.
Step 13. File sole of foot using an abrasive foot file until the dead skin rolls off the foot file, and refine with the softer side of the foot file.
Step 14. Unwrap second foot, and repeat steps 12 and 13.
Step 15. Wipe both feet clean with a steamed towel to remove residual callus softener and skin debris.
Step 16. Apply a fruit acid-based softener cream to both feet.
Step 17. Gently clean under toenails using a precision tool or orangewood stick.
Step 18. If the client requested polish on toes, add the steps for polish application protocol here.
Step 19. Massage feet and legs using a no-rinse scrub and a moisturizing cream as a relaxing treatment and good ending to a wellness spa pedicure.
Note: Our feet could signal potential health issues before they become serious. Diagnosing adverse health conditions is a no-no for nail professionals, so stay in your scope of practice. Do be observant and suggest that the client checks with a physician if something abnormal about the feet or toes presents during the pedicure service.
There are retail options for clients to maintain their feet at home between services. These include the moisturizing cream used in the pedicure, a fruit acid-based softener to apply daily on the soles of the feet and toes and the nail and cuticle oil used in the pedicure.
About the author:
Vivian Valenty, Ph.D., is the founder and president of VB Cosmetics, the maker of Dazzle Dry. She obtained her doctorate in chemistry from Penn State University, and she has a passion for combining wellness with performance.