Other types of subungual nail fungus infections include lateral subungual (spreading along the side of the nail), and proximal subungual (starting near the cuticle and root of the nail). All of these forms of the infection tend to involve dermatophytes - fungi that are specially adapted to grow in nails, skin, and hair - but distal subungual onychomycosis is by far the one most commonly seen. Lateral infections usually accompany the distal form while proximal infections are quite rare and tend to occur in cases of nail injury or in patients whose immune system is not functioning properly.

After lateral and distal subungual onychomycosis, the next most common type of fungal nail infection is white superficial onychomycosis. As the name implies, in this condition the fungus invades the nail from the top surface, producing a white patch that spreads to cover the entire surface over time. The infection usually involves the toenails. Like subungual nail fungus, superficial infections are usually caused by dermatophytes, though the fungal species involved may be different. Only about ten percent of fungal nail infections are superficial. This type of infection probably responds better to topical antifungal treatments because the thickness of the nail does not lie between the treatment and the fungus.

All nail conditions suspicious of distal subungual onychomycosis, and indeed any form of fungal nail infection, should be properly diagnosed by a medical professional. Just as there are different types of fungal nail infections, there are also other conditions that can cause deformation and discoloration of nails. Some of these look surprising like superficial or subungual nail fungus - be sure that fungus is the cause of your nail problem before attempting to treat it. Once you are sure of the diagnosis, you can choose between prescription drugs for onychomycosis, an alternative nail fungus remedy, or one of the traditional home remedies.

R. Drysdale is a freelance writer with more than 25 years experience as a health care professional. She is a contributing editor to Distal Subungual Onychomycosis at Nail Fungus Treatment, a blog dedicated to the treatment of fingernail and toenail fungus.