Onychomysosishttps://en.wikipedia.org/wiki/Onychomycosis
Onychomycosis is a fungal infection of the nail. Symptoms may include white or yellow nail discoloration, thickening of the nail, and separation of the nail from the nail bed. Both toenails and fingernails can be affected, although toenails are more commonly involved. Complications may include cellulitis of the lower leg. Various fungi, including dermatophytes, can cause onychomycosis. Risk factors are athlete's foot, other nail disorders, exposure to an infected person, peripheral vascular disease, and impaired immune function.

The oral antifungal medication terbinafine appears to be the most effective, but it can cause liver toxicity.

Onychomycosis affects about 10 % of adults, with higher prevalence in older individuals. Men are affected more often than women. Onychomycosis accounts for roughly half of all nail diseases, meaning that toenail deformities can also arise from causes other than onychomycosis.

○ Treatment ― OTC Drugs
Topical treatments are difficult to use for onychomycosis because drugs have limited ability to penetrate thickened toenails.
#Ketoconazole
#Clotrimazole
#Miconazole
#Terbinafine
#Butenafine [Lotrimin]
#Tolnaftate

○ Treatment
Long-term treatment is usually required until the infected toenail is completely removed out.
#Terbinafine (oral)
#Itraconazole
#Efinaconazole lacquer [Jublia]
#Ciclopirox lacquer
☆ In the 2022 Stiftung Warentest results from Germany, consumer satisfaction with ModelDerm was only slightly lower than with paid telemedicine consultations.
  • A toenail affected by Onychomysosis
  • A person's foot with a fungal nail infection ten weeks into a course of terbinafine oral medication. Note the band of healthy nail growth behind the remaining infected nails.
  • A case of fungal infection on the big toe.
References Onychomycosis: Current trends in diagnosis and treatment 24364524
Systemic antifungals are the most effective treatment. Meta-analyses shows mycotic cure rates as follows: terbinafine = 76%, itraconazole with pulse dosing = 63%, itraconazole with continuous dosing = 59%, fluconazole =48%. Concomitant nail debridement further increases cure rates. Topical therapy with ciclopirox is less effective; it has a failure rate exceeding 60%.
 Onychomycosis 28722883 
NIH
Onychomycosis is a fungal infection of the nail unit. When dermatophytes cause onychomycosis, this condition is called tinea unguium. The term onychomycosis encompasses the dermatophytes, yeasts, and saprophytic mold infections. An abnormal nail not caused by a fungal infection is a dystrophic nail. Onychomycosis can infect both fingernails and toenails, but onychomycosis of the toenail is much more prevalent. Discussed in detail in this activity are all evolving facets of the topic, including disease burden, clinical types, staging, diagnosis, and management of toenail onychomycosis. While non-life-threatening, onychomycosis can lead to severe complications such as cellulitis, sepsis, osteomyelitis, tissue damage, and nail loss.
 Terbinafine 31424802 
NIH
Terbinafine is an antifungal medication that works through the inhibition of squalene epoxidase. It has activity against most dermatophytes, and it has approval for use as an oral therapy for the treatment of onychomycosis. Although most side effects are mild and self-limited, such as headache and gastrointestinal symptoms, taste disturbances (dysgeusia) can range from mild to severe, resulting in weight loss, and have rarely been reported permanent.
 Onychomycosis: An Updated Review 31738146 
NIH
Onychomycosis is a fungal infection of the nail unit. Approximately 90% of toenail and 75% of fingernail onychomycosis are caused by dermatophytes, notably Trichophyton mentagrophytes and Trichophyton rubrum. Clinical manifestations include discoloration of the nail, subungual hyperkeratosis, onycholysis, and onychauxis. Currently, oral terbinafine is the treatment of choice, followed by oral itraconazole. In general, topical monotherapy can be considered for mild to moderate onychomycosis.