On this page
- TL;DR
- The Current DC 7813 Rating
- The General Rating Formula for the Skin provides:
- Area Evidence for Nail Disease
- Diagnosis and Treatment Evidence
- Direct Service Connection
- Secondary to Diabetes or Another Condition
- Alternative Skin Rating Routes
- What the C&P Record Should Establish
- The record should answer:
- Common Failure Modes
- Bottom Line
VA expressly includes tinea unguium, or onychomycosis, under Diagnostic Code 7813 for dermatophytosis. It is generally evaluated under the General Rating Formula for the Skin in 38 CFR § 4.118, using either the percentage of body or exposed area affected or the duration of qualifying systemic therapy during the previous 12 months.
Many nail-only cases fall at 0 percent because the affected area is small and treatment is topical. A compensable rating can still be supported when the documented area or systemic-treatment criteria are met.
TL;DR
- Onychomycosis is listed under DC 7813 as tinea unguium.
- DC 7813 generally uses the 0, 10, 30, and 60-percent General Rating Formula for the Skin.
- The formula has two routes: affected body/exposed area or qualifying systemic therapy in the last 12 months.
- Topical therapy applied through the skin is treated differently from therapy administered by another route.
- Oral antifungal prescriptions, dates, and duration should be documented rather than summarized from memory.
- Nail changes have several nonfungal causes, so testing and a clinician's diagnosis can be important.
- Direct onset or continuity may be viable; diabetes may support a secondary theory only with a case-specific causation or aggravation opinion.
- Painful scars, disfigurement, or another rating route applies only when the facts and predominant disability satisfy that code.
The Current DC 7813 Rating
The General Rating Formula for the Skin provides:
60 percent
Characteristic lesions involving more than 40 percent of the entire body or exposed areas, or constant or near-constant systemic therapy during the past 12 months.
30 percent
Characteristic lesions involving 20 to 40 percent of the entire body or exposed areas, or systemic therapy for six weeks or more but not constantly during the past 12 months.
10 percent
Characteristic lesions involving at least 5 but less than 20 percent of the entire body or exposed areas, or intermittent systemic therapy for less than six weeks during the past 12 months.
0 percent
Characteristic lesions involving less than 5 percent of the entire body and exposed areas, with no more than topical therapy during the past 12 months.
The regulation defines systemic therapy as treatment administered through a route other than the skin and topical therapy as treatment administered through the skin. The formula lists examples of systemic treatment but is not limited to those examples. For an oral antifungal, the record should identify the drug, route, dates, and total duration, while the rating decision should explain how that treatment fits the current formula.
Area Evidence for Nail Disease
The body-area route can be difficult for nail-only disease because nails occupy a small percentage of the entire body. The examination should still identify every affected nail, whether fingers or toes are involved, whether surrounding skin is affected, and whether a related fungal skin condition such as tinea pedis is part of the same service-connected disease process.
Photographs can show appearance and progression, but the percentage determination should come from a competent examination. A veteran should not estimate a body-surface percentage without medical support.
Diagnosis and Treatment Evidence
The Centers for Disease Control and Prevention notes that nails can discolor or change shape for many reasons and recommends testing before treatment for a suspected fungal infection. Oral prescription antifungal medicine is often used, treatment may take months, and infection can return.
Useful compensation evidence can include:
- dermatology or podiatry diagnosis;
- KOH preparation, culture, pathology, or other testing when performed;
- photographs taken over time;
- the number and location of affected nails;
- concurrent fungal skin findings;
- topical and oral medication histories with exact dates; and
- records of pain, nail loss, secondary infection, or functional limits.
Testing is strong evidence, but this guide does not declare one laboratory method legally mandatory in every VA claim. The key is a medically supported diagnosis that distinguishes fungal disease from trauma, psoriasis, pigment changes, or another nail disorder.
Direct Service Connection
Direct service connection under § 3.303 may apply when fungal nail disease began in service. Service treatment records may describe tinea, nail changes, foot complaints, or treatment. Lay evidence can describe observable thickening, discoloration, crumbling, and recurrence, but a clinician should establish the current diagnosis.
Communal showers, prolonged boot wear, humid environments, and field conditions may be relevant to the history. They are not automatic proof of nexus. The opinion should explain why the veteran's current disease is connected to the in-service onset or exposure rather than a later infection or another cause.
Secondary to Diabetes or Another Condition
The CDC notes that people with diabetes have a higher risk of recurrent fungal nail infections. A claim under § 3.310 still needs an individualized medical opinion showing that service-connected diabetes caused or aggravated this veteran's onychomycosis.
Risk is not the same as causation. The opinion should address timing, circulation, immune status, recurrence, treatment response, and other risks. For aggravation, it should identify the worsening attributable to the service-connected condition where feasible.
Alternative Skin Rating Routes
DC 7813 allows evaluation as disfigurement of the head, face, or neck or as scars when that is the predominant disability. Those routes are uncommon for ordinary toenail fungus and should not be added automatically. The medical facts must show the qualifying location and impairment.
Separate ratings for overlapping manifestations are prohibited by § 4.14. When several fungal diagnoses affect the same area, VA should avoid counting the same lesions or treatment twice.
What the C&P Record Should Establish
The record should answer:
- Is the nail condition medically diagnosed as onychomycosis?
- Which nails and surrounding skin areas are affected?
- What percentage of the whole body and exposed areas is involved?
- What topical and systemic treatments were used in the previous 12 months?
- What were the route and total duration of each treatment?
- When did observable disease begin, and has it recurred continuously?
- Does a service-connected condition cause or aggravate it?
- Is another diagnosis a better explanation for the nail changes?
Common Failure Modes
- Using DC 7820 when DC 7813 expressly lists tinea unguium or onychomycosis.
- Assuming every oral prescription guarantees a particular percentage without documenting duration and the current formula.
- Calling topical medication systemic solely because it has effects beyond the application site.
- Estimating body-surface percentages without an examination.
- Treating discoloration alone as proof of fungal disease.
- Assuming communal living or diabetes establishes nexus without a case-specific opinion.
- Counting the same lesions and therapy under multiple skin diagnoses.
Bottom Line
An onychomycosis claim should document the fungal diagnosis, every affected nail and skin area, the exact route and duration of treatment during the prior 12 months, and the service-connection timeline. The rating usually turns on small-area versus systemic-treatment evidence, not on how unpleasant the nail appearance is by itself.
Legal and medical sources: 38 CFR § 4.118, § 3.303, § 3.310, § 4.14, and CDC fungal nail treatment guidance, checked August 14, 2026.