But the terbinafine treatment costs only $10 (plus an additional $43 for liver function tests). In conclusion the authors say that terbinafine has a relatively benign adverse effect profile, with liver damage very rare, so it makes more sense cost-wise for the dermatologist to prescribe the treatment without doing the PAS test. (Another option would be to prescribe the treatment only if the potassium hydroxide test is positive, but it gives a false negative in about 20% of cases of fungal infection.) On the other hand, as of 2015 the price of topical (non-oral) treatment with efinaconazole was $2307 per nail, so testing is recommended before prescribing it.The cost of efinaconazole treatment can be reduced to $65 per 1-month dose using drug coupons, bringing the treatment cost to $715 per nail. Canada
In 2019, a study by the Canadian Agency for Drugs and Technologies in Health found the cost for a 48-week efinaconazole course to be $178 for a big toe, and $89 for an other toe. Prognosis
Recurrence may occur following treatment, with a 20-25% relapse rate within 2 years of successful treatment. Nail fungus can be painful and cause permanent damage to nails. It may lead to other serious infections if the immune system is suppressed due to medication, diabetes or other conditions. The risk is most serious for people with diabetes and with immune systems weakened by leukemia or AIDS, or medication after organ transplant.
A laboratory test should be performed to confirm. Proximal subungual onychomycosis is fungal penetration of the newly formed nail plate through the proximal nail fold. It is the least common form of tinea unguium in healthy people, but is found more commonly when the patient is immunocompromised. Endonyx onychomycosis is characterized by leukonychia along with a lack of onycholysis or subungual hyperkeratosis. Candidal onychomycosis is Candida species invasion of the fingernails, usually occurring in persons who frequently immerse their hands in water. This normally requires the prior damage of the nail by infection or trauma. Differential diagnosis
In many cases of suspected nail fungus there is actually no fungal infection, but only nail deformity.To avoid misdiagnosis as nail psoriasis, lichen planus, contact dermatitis, nail bed tumors such as melanoma, trauma, or yellow nail syndrome, laboratory confirmation may be necessary.Other conditions that may appear similar to onychomycosis include: psoriasis, normal aging, yellow nail syndrome, and chronic paronychia. Treatment
Medications
Most treatments are with antifungal medications, either topically or by mouth. Avoiding use of antifungal therapy by mouth (e.g., terbinafine) in persons without a confirmed infection is recommended, because of the possible side effects of that treatment.Medications that may be taken by mouth include terbinafine (76% effective), itraconazole (60% effective), and fluconazole (48% effective). They share characteristics that enhance their effectiveness: prompt penetration of the nail and nail bed, and persistence in the nail for months after discontinuation of therapy. Ketoconazole by mouth is not recommended due to side effects. Oral terbinafine is better tolerated than itraconazole.