Toenail fungus is a common problem. Doctors call it onychomycosis. The nail becomes thick and yellow. Sometimes it crumbles or falls off. Millions of people deal with this issue each year. Athletes get it often, and older adults are at higher risk, too.
Getting paid for toenail fungus treatment can be tricky. Medical billing has many rules. This guide will help you bill correctly and avoid denials.
Common CPT Codes for Toenail Fungus
CPT codes tell insurers what service you provided. Using the right code is crucial for payment.
Nail Trimming Codes
11719
This code covers trimming one to five nails. Use it for basic nail care with fungus present.
11721
This applies when trimming six or more nails. Both codes include removing debris under the nail.
Many practices use these codes weekly. Patients with diabetes often need regular nail care.
Nail Removal Codes
11730
Use this for removing part of a nail. This is common when fungus affects just one section.
11732
This covers removing an entire nail. Severe fungus cases may require full removal.
11750
This code is for permanent nail removal. The doctor destroys the nail matrix to prevent regrowth.
Biopsy and Culture Codes
11755
This applies to nail biopsies. Taking a sample helps confirm fungus diagnosis.
87101
Use this code for fungal cultures. Labs grow the fungus to identify the exact type.
Getting the right diagnosis matters. Culture results guide treatment choices.
ICD-10 Codes You Need to Know
Diagnosis codes explain why treatment was needed. They justify the services you billed.
Primary Fungus Codes
B35.1 – This is the main code for toenail fungus. It covers fungal infection of the nail.
Use this code when fungus is the primary problem. Most toenail fungus cases use this diagnosis.
Location Specific Codes
Some insurers want more detail. They may ask which toe was treated.
B35.1 still works in most cases. Check your payer’s guidelines to be sure.
Related Condition Codes
Sometimes other issues exist alongside fungus. Code all relevant diagnoses.
E11.621 – Type 2 diabetes with foot ulcer I70.242 – Arterial disease of the left leg L60.0 – Ingrown nail
These secondary codes support medical necessity. They show why treatment was urgent or complex.
Medical Necessity Requirements
Insurance won’t pay without medical necessity. You must prove treatment was needed, not cosmetic.
Documentation Tips
Your notes should paint a clear picture. Describe the nail’s appearance in detail.
Include these elements:
- Nail thickness and color changes
- Pain level and impact on walking
- Previous treatments tried
- Risk factors like diabetes
Photos help tremendously. Visual proof supports your case when claims are reviewed.
When Treatment Is Medically Necessary
Certain situations make treatment clearly necessary. Insurers approve these cases more readily.
Pain that limits daily activities qualifies. Infection spreading to surrounding skin counts too.
Patients with diabetes need special attention. Poor circulation makes fungus dangerous for them.
Immunocompromised patients also qualify. Their bodies can’t fight fungus effectively alone.
Medicare Billing Guidelines
Medicare has specific rules for nail care. Class findings determine coverage.
Understanding Class Findings
Medicare created a classification system. It has four classes labeled A through D.
Class A – Involves systemic disease. Examples include diabetes with neuropathy.
Class B – Covers severe nail problems. This includes thick, painful nails from fungus.
Class C – Applies to less severe cases. The patient may have some discomfort.
Class C cases usually aren’t covered. Treatment is deemed cosmetic without other factors.
Q Modifier Requirements
Medicare requires special modifiers. These show the patient’s risk level.
Q7 – Use for Class A patients. One finding from the approved list qualifies them.
Q8 – Use for Class B patients. Two findings from the list are needed.
Q9 – Use for Class C patients. Three findings must be present for coverage.
Document each finding clearly. Medicare audits happen, and you’ll need proof.
Frequency Limitations
Medicare limits how often it’ll pay. Routine nail care is typically covered every 60 days.
Some exceptions exist for high-risk patients. Those with severe complications may qualify for more frequent care.
Always check the last service date. Billing too soon triggers automatic denials.
Private Insurance Guidelines
Each private payer has different rules. Review policies before submitting claims.
Pre-Authorization Needs
Some insurers require approval first. Call before providing expensive treatments.
Oral medications often need pre-authorization. Laser treatments usually do too.
Get approval in writing. Keep this documentation with your claim records.
Coverage Variations
Benefits vary widely between plans. What one insurer covers, another denies.
Many plans exclude cosmetic nail care. They only pay when medical necessity exists.
High-deductible plans shift costs to patients. Explain financial responsibility upfront.
Appealing Denials
Denials happen even with perfect coding. Don’t give up after the first rejection.
Write a clear appeal letter. Explain why treatment was medically necessary.
Include supporting documents:
- Office visit notes
- Culture results
- Photos of the affected nails
- Treatment history
Many denials get reversed on appeal. Persistence pays off for your practice.
Oral Medication Billing
Prescription antifungals work from inside the body. These medications require special billing steps.
Common Medications
Terbinafine – Sold as Lamisil, this is a first-line treatment. Patients take it for twelve weeks.
Itraconazole – Known as Sporanox, this works well too. Dosing schedules vary by patient.
Fluconazole – This option works but less commonly gets used for nails.
Pharmacy vs Medical Billing
Patients usually get prescriptions filled at pharmacies. The pharmacy bills their insurance directly.
Your office bills for the visit where you prescribed medication. Use an evaluation and management code.
Some practices dispense medications directly. This requires different billing procedures and licenses.
Lab Monitoring Codes
Oral antifungals can affect the liver. Patients need blood tests before and during treatment.
80076 – This is the hepatic function panel. It checks liver enzyme levels. Bill these separately from the office visit. Document medical necessity for testing.
Office-Applied Treatments
Some treatments happen in your office. These get billed under your practice. Urea paste helps soften thick nails. This makes removal easier and less painful. Antifungal solutions can be applied professionally. Some insurers cover these office treatments.
Compound Medications
Custom-mixed medications may work better. Compounding pharmacies create these special formulas. Billing can be complex with compounds. Work closely with the pharmacy on coding. Some insurers don’t cover compounded drugs. Verify benefits before ordering.
Laser Treatment Billing
Laser therapy offers a non-drug option. Insurance coverage remains limited for this treatment.
CPT Code Challenges
- No specific CPT code exists for fungal laser treatment. This creates billing difficulties.
- Some practices use unlisted codes. 17999 covers unlisted laser procedures.
- Others bill using 97039 for unlisted physical medicine. This approach works sometimes.
Surgical Procedure Billing
Severe cases may need surgery. These procedures require detailed documentation.
Partial Nail Removal
Code 11730 covers partial removal. This works for localized fungus affecting part of the nail. Include the specific toe treated. Note whether you used local anesthesia. Document the portion removed. “Medial third of great toenail” gives clear detail.
Complete Nail Removal
Use code 11732 for total nail removal. The entire nail plate comes off. This is more invasive than partial removal. Bill accordingly and document complexity. Explain why complete removal was necessary. Perhaps fungus affected the whole nail bed.
Permanent Nail Removal
Code 11750 covers matrixectomy procedures. The nail won’t grow back after this surgery. Chemical matrixectomy uses phenol or sodium hydroxide. Physical matrixectomy cuts out the matrix tissue. This is the most complex nail procedure. Insurance usually covers it for chronic, painful cases.
Modifier Usage
Add modifiers to show which toe was treated. This matters for bilateral procedures.
- 50 indicates bilateral procedures. Use when treating the same toe on both feet.
- 59 shows distinct procedures. Apply when doing different treatments the same day.
- 25 allows an E&M code with a procedure. Document a significant, separate evaluation occurred.
Staying Updated
Billing rules change constantly. Make time to stay informed about updates. Join professional organizations. APMA and AAFP provide coding resources. Attend webinars on billing topics. Many are free and offer continuing education credit. Subscribe to coding newsletters. Quick email updates keep you current without overwhelming you.
Working with Billing Companies
Many practices outsource billing. This can improve cash flow and reduce headaches. Look for companies with podiatry experience. General billers may miss specialty nuances. Ask about their denial rate. Good billing companies keep denials under ten percent. Check their fee structure. Most charge a percentage of collections, typically four to eight percent.
Conclusion
Billing for toenail fungus requires attention to detail. Correct codes, proper documentation, and knowledge of payer rules all matter.
Stay educated about billing changes. Build strong systems in your practice. Communicate clearly with patients about costs. These steps lead to better reimbursement. They also reduce stress for your staff and patients. Good billing practices support good patient care. Contact billingpodiatry.com for podiatry billing services.
FAQs
What is considered a severe case of toenail fungus?
In severe cases, the nails can loosen or come off completely. Nail fungal infections are more common in the toenails than the fingernails because: Socks and closed shoes provide perfect conditions for fungi to grow. Toenails are more likely to be injured by shoes and activities.
What is the gold standard for toenail fungus?
Prescription Oral Antifungals (e.g., Terbinafine)
These are considered the gold standard. Taken for 6–12 weeks, they treat fungus from the inside out 00by penetrating the nail bed and bloodstream. Studies show up to 76% effectiveness after 3–4 months.
How much does Medicare pay for toenail debridement?
Part B generally does not cover routine foot-care services such as the cutting or removal of corns and calluses or trimming, cutting, clipping, or debridement (i.e., reduction of both nail thickness and length) of toenails.