Why Nail Fungus Treatments Don't Work & What to Do About It
Todd Weinfield
Ever wonder why the topical nail fungus treatments you've tried don't work? There are many treatments on the market, and despite their claims, your nails are still infected. Here's why:
The Obstacles
Water Solubility. The first obstacle is getting the medication to the infection. The nail becomes a barrier that keeps the medication from reaching the infection. Worse, the infection creates another layer or structure underneath the outer nail under which the infection can hide. During its lifetime, the infection continually builds this layer, thickening the nail and making the condition more difficult to treat over time.
Fortunately, the nail and underlying structure love to absorb water - especially warm water - which is why your nails become soft after a warm shower. Most topical medications do not dissolve in water and and are unable to penetrate the nail. The medications we use in our ToeMate® line are water soluble and are carried through the nail with the warm water to treat the infection.
Energy. The second obstacle is energy. Most medications are applied at room temperature (for convenience and because they denature at higher temperatures) even though more energy is needed to penetrate the nail (why nails soften in warm bath water but less so in cold water). This is why ToeMate® soaks infected nails in warm medication we call thermal solution.
Nail Thickness. The third obstacle is nail thickness. Even with warm water and soluble medication, the increased nail thickness substructure makes it difficult for the medication to reach the infection. Included in our ToeMate® kits is a nail cleaner that removes the underlying structure and facilitates thermal solution delivery to the infection. For this reason, treatment times using ToeMate® kits are shorter than other treatments, usually only up to 3 months instead of 9 to 12 months.
Modes of Action. The fourth obstacle is most topical treatments have too few weapons or modes of action to effectively treat infections. Instead of only one or two modes of action, the thermal solution in ToeMate® kits has 6 or more making it difficult for the infection to survive. The table below includes modes of action and water solubility for several popular nail fungus treatments and compares them with those used in ToeMate® kits.
Limitations of Existing Treatments
1) Oral treatments include Griseofulvin (Gris-PEG), Ketoconazole (Nizoral), Lamisil (Terbinafine), Sporanox (Itraconazole), and Posaconazole (Noxafil), and Albaconazole. Lamisil has been the most effective with a mycological cure rate of 40% and a nine month treatment course for $1,350 to $2,700. The limited success of Lamisil in the market is attributed to its potential for toxic side effects, high relapse rate, long treatment times, marginal cure rates, and the tendency of the infection to inhabit portions of the nail that do not have a blood supply. Posaconazole and Albaconazole have posted similar results with fewer toxic side effects.
2) Topical treatments include amorolfine (Loceryl), ciclopirox (Penlac), Kerydin (Tavaborole) . Efinaconazole (Jublia), luliconazole (Lulicon). Amorolfine and Ciclopirox provide the highest topical cure rates, however those rates are much lower than those for systemic medications. Amorolfine does not have FDA approval. Amorolfine has shown cure rates of 40 to 55% for mild onychomycosis without nail matrix involvement, however, it is not effective against severe onychomycosis involving the nail bed (nine month treatment course costs $1,080). Ciclopirox (Penlac) and Efinaconazole (Jublia) are the only FDA approved medications for this condition and have cure rates about 8.5% and 17.8% respectively for mild infections not involving the nail bed. Placebo cure rate is 6%.
Kerydin (Tavaborole) achieved complete cure in 6% of the 600 patients in a recent study. Other topical treatments of less interest include: Cindacin (DSMO and tolnaftate from Pedicis Research); Emtrix, Nalox, and Kerasal Nail (urea, propylene glycol and lactic acid from Paladin Labs) are used to treat symptoms of onychomycosis.
3) Light, electromagnetic, and gas plasma Companies such as Keraderm, Patholase, Nomir, and Devicefarm have developed light energy and gas plasma technology to treat infections taking advantage of UV, laser light and chlorine gas plasma's ability to inhibit fungal growth in vitro. The build up of keratin debris under the nail plate prevents light and plasma from penetrating the nail. The best published effective rate for light energy is Patholase with a 10% cure rate (placebo is 6%) administered during an office visit for $900 – $1,200 per application. Devicefarm gas plasma ($1,500 to $2,000 for three office visits) has not published the results from their clinical trial.
4) Iontophoresis, electrophoresis and implant startups that developed electrophoresis techniques to transport medication through the nail have not been successful (e.g., NB Therapeutics) and Lamisil implant startup Hallux (formerly Talima) has only started recruiting for clinical trials.