ICD-10 Code L88: Pyoderma gangrenosum coding reference
L88 is the billable ICD-10-CM code for pyoderma gangrenosum. One Excludes1 note ...
Last Updated: August 4, 2026
Key takeaways
ICD-10 code M83.5 describes other drug-induced osteomalacia in adults, a billable FY2026 diagnosis code applicable to patients 15 years and older.
Anticonvulsants, corticosteroids, tenofovir, and certain antacids are among the drug classes most commonly linked to this diagnosis.
The Excludes1 note under M83 bars rickets, renal osteodystrophy, and vitamin D-resistant osteomalacia from the same claim as M83.5.
Pabau’s claims management software and client record tools help practices document drug history accurately, reducing denials.
ICD-10 code M83.5 is the billable ICD-10-CM code for other drug-induced osteomalacia in adults. It applies when a documented medication has impaired bone mineralization in a patient aged 15 or older. Practices that reach for an unspecified osteomalacia code instead lose that specificity and invite payer queries.
The FY2026 edition of M83.5 took effect on October 1, 2025. Coders in endocrinology, orthopedics, internal medicine, and neurology meet it most often, since those practices manage long-term anticonvulsant and corticosteroid regimens. This guide covers the code details, causative drug classes, the Excludes1 note, sibling codes, documentation requirements, and common coding errors.
ICD-10 code M83.5: code details at a glance
ICD-10 code M83.5 is a billable, specific ICD-10-CM diagnosis code. It can be used directly for reimbursement without further subdivision. The table below captures the key reference fields coders need when working with this code.
Per the CDC/NCHS ICD-10-CM web tool, M83.5 is valid for use in all settings for encounters on or after October 1, 2025. It is not a placeholder or header code; it requires no additional characters to be billable.
What is drug-induced osteomalacia?
Osteomalacia is the softening of bone tissue caused by defective mineralization. Unlike osteoporosis, which reduces bone density after mineralization has occurred, osteomalacia affects the mineralization process itself, leaving the bone matrix inadequately calcified.
Drug-induced osteomalacia happens because a medication interferes with either vitamin D metabolism or phosphate absorption. Long-term disruption of either pathway costs the skeleton its structural integrity. The result is bone pain, proximal muscle weakness, and raised fracture risk in affected adults.
Nutritional osteomalacia sits elsewhere. Diet or sun exposure drives it, and vitamin D deficiency is coded under E55.x. M83.5 needs a prescribed or over-the-counter drug behind the mineralization defect. Bone pain and proximal muscle weakness also appear in M79.7, so the record must tie the findings to that drug.
Medications that can cause M83.5
Several drug classes are associated with impaired bone mineralization in adults. Practices that treat patients on long-term anticonvulsant, antiretroviral, or corticosteroid regimens should include drug-induced osteomalacia in their differential when bone-related symptoms arise. Good clinical record documentation of prescribing history is what makes this code defensible at audit.
Anticonvulsants are the most commonly implicated class. Clinical literature links more than two years of enzyme-inducing anticonvulsant therapy to defective bone mineralization. The risk climbs when vitamin D supplementation is not co-prescribed.
Corticosteroids raise a harder question. Patients on long-term steroid therapy for a condition such as M32.9 often carry several bone-relevant exposures at once. Name the drug the physician holds responsible, rather than everything sitting on the medication chart.
When M83.5 applies and what the Excludes1 note blocks
The Excludes1 note under M83 governs which codes can share a claim with M83.5. Misreading it is a common source of denials for osteomalacia diagnoses. The CMS ICD-10 codes page publishes the annual tabular list where the note appears in its authoritative form.
When M83.5 applies
M83.5 applies only when the record names the drug behind the osteomalacia. No Includes note at M83.5 or M83 supplies that requirement. Without a documented causative medication, unspecified adult osteomalacia defaults to M83.9.
Excludes1 note (strict rule)
The Excludes1 notation for the M83 category means the following conditions are mutually exclusive with M83.5 and cannot appear on the same claim:
- Infantile and juvenile osteomalacia (E55.0)
- Renal osteodystrophy (N25.0)
- Rickets (active) (E55.0)
- Rickets (active) sequelae (E64.3)
- Vitamin D-resistant osteomalacia (E83.31)
- Vitamin D-resistant rickets (E83.31)
This is a hard rule. If a patient has both a drug-induced component and an active rickets diagnosis, M83.5 and E55.0 cannot appear on the same claim. The coder must select the code that best represents the primary diagnosis and query the physician if the documentation is ambiguous.
M83 parent category and sibling codes
ICD-10 code M83.5 sits within the M83 adult osteomalacia category. Understanding the full sibling code set helps coders select the most specific code for each clinical scenario. The table below lists all M83 subcategory codes valid for FY2026, per the WHO ICD-10 browser and the US ICD-10-CM tabular list.
M83.4 and M83.5 are easy to confuse. Aluminum bone disease in dialysis patients follows its own pathophysiology, driven by aluminum accumulation in the skeleton. M83.5 covers drug-induced impairment through the vitamin D or phosphate route. A patient on high-dose aluminum antacids who is not on dialysis belongs in M83.5.
Documentation requirements for ICD-10 code M83.5
The medical record must support every element of the M83.5 diagnosis before the code can be assigned. Missing documentation is the primary reason this code is queried or denied. Practices using digital intake forms to capture full medication history at intake are better positioned to build the supporting documentation trail from the first visit.
The following documentation elements are required:
- Confirmed drug causation: the physician must document which specific medication is suspected or confirmed as the causative agent. Osteomalacia alone is insufficient. The note must establish the drug-bone connection.
- Laboratory findings: low serum 25-hydroxyvitamin D, hypophosphatemia, elevated alkaline phosphatase, or low serum phosphate strengthen the clinical case. At least one abnormal bone-metabolism marker should appear in the record.
- Prescribing history: duration of drug exposure matters. The record should show when the causative drug was initiated and, if known, the cumulative dose or duration that preceded symptom onset.
- Clinical evaluation: a physician note documenting bone pain, proximal muscle weakness, or gait changes attributed to medication-related bone disease.
- Age documentation: M83.5 is applicable to patients 15 years and older only. The patient’s age at the encounter must be evident in the record.
Practices managing patients with complex polypharmacy histories benefit from HIPAA-compliant documentation workflows that maintain a complete and searchable medication record. When the prescribing history spans multiple providers, the coder should ensure all relevant drug information is consolidated in the chart before assigning M83.5.
Common coding errors and how to avoid them
Osteomalacia coding generates a predictable set of errors. Each one is catchable at the billing desk before the claim goes out.
- Defaulting to M83.9 (unspecified): this is the most frequent error. When the physician’s notes identify the causative drug, the coder must use M83.5, not the unspecified code. Using M83.9 when a more specific code exists can signal incomplete coding to payers and may trigger a query or lower reimbursement.
- Confusing M83.5 with E55.0 (rickets): rickets is a pediatric condition involving active vitamin D deficiency with growth plate involvement. Applying E55.0 or rickets-related codes to an adult patient with drug-induced bone softening is incorrect. The Excludes1 note makes clear these cannot coexist on the same claim.
- Omitting the causative drug link: assigning M83.5 when the documentation says only “osteomalacia” or “bone pain” is unsupported coding. The drug-cause relationship must be explicit in the physician’s documentation.
- Applying M83.5 to pediatric patients: this code applies to patients 15 years and older. For younger patients with drug-induced bone pathology, a code from the E55 or E83 range fits the mechanism better. Pediatric bone disorders outside those ranges, such as M91.91, follow their own coding rules.
- Conflating M83.5 with M83.4: aluminum bone disease in dialysis patients is M83.4. While aluminum-containing antacids at very high doses may contribute to M83.5, dialysis-associated aluminum accumulation is a separate and distinct condition.
Accurate coding depends on the clinical record, the payer’s coverage policies, and the AAPC ICD-10-CM code lookup resources that help coders verify code-level details. When in doubt, query the physician before submitting.
Approximate synonyms and clinical terms for M83.5
Physician notes and EMR problem lists often use terminology that differs from the official code descriptor. Knowing the approved synonyms helps coders map clinical language to M83.5 accurately. Mapping those phrases consistently keeps the diagnosis intact from the encounter note through to the claim, which is where patient data workflows pay off.
- Drug-induced osteomalacia
- Drug-induced osteomalacia in adult
- Medication-induced osteomalacia
- Anticonvulsant-induced osteomalacia
- Anticonvulsant osteomalacia
- Drug-induced adult bone softening
- Drug-induced impaired bone mineralization (adult)
When reviewing physician notes, also watch for phrases like “osteomalacia secondary to [drug name]” or “bone disease related to [anticonvulsant/antacid/antiretroviral].” These narrative formulations, when written by the responsible physician, support M83.5 assignment.
Code history and annual updates
M83.5 has remained structurally stable through several ICD-10-CM fiscal year editions. The table below confirms its status across recent years, based on the CMS ICD-10-CM annual update files.
Coders should verify code status at the start of each fiscal year using the CDC/NCHS web tool or the CMS update files. Practices using practice management software with integrated coding tools stay current on annual ICD-10-CM updates without manual tracking.
How Pabau supports M83.5 documentation and claim accuracy
Most coding errors involving M83.5 start at intake rather than at the billing desk. When medication history is incomplete or stored apart from the clinical notes, coders cannot build the documentation chain M83.5 requires. Practice management software like Pabau links its claims management software to the clinical record, so nothing is lost in the handoff.
Practices using Pabau can capture structured medication histories at intake and write clinical notes that state the drug-disease relationship in the physician’s own words. That documentation is what makes M83.5 auditable when a payer requests supporting records.
Practices with polypharmacy panels get more out of that setup. Pabau’s functional medicine software workflows coordinate care across prescribers and hold one unified medication record. For bone and metabolic conditions, metabolic health EMR tools put coding and documentation in the same place, which cuts admin time and claim errors.
Reduce ICD-10 coding errors with better documentation workflows
Pabau connects medication history, clinical notes, and billing in one platform. See how structured documentation workflows reduce claim denials for diagnostic codes like M83.5.
Conclusion
M83.5 rewards one habit above all others. When the physician names the drug in the assessment and the labs back it up, the code is defensible and the claim holds. Reaching for M83.9 instead trades that specificity for nothing.
The trade-off worth remembering is where the drug link lives. A medication list alone will not carry it. Put the causation statement in the physician’s note, and the coding follows. Book a demo to see how Pabau keeps medication history, clinical notes, and billing in one record.
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Frequently asked questions
What is ICD-10 code M83.5?
ICD-10 code M83.5 is the billable ICD-10-CM diagnosis code for other drug-induced osteomalacia in adults. It describes adult-onset bone softening caused by a specific medication interfering with vitamin D metabolism or phosphate absorption. The code is valid for FY2026 and applicable to patients aged 15 years and older.
Is M83.5 a billable ICD-10-CM code?
Yes. M83.5 is a specific, billable ICD-10-CM code that requires no additional characters. It became effective on October 1, 2025 for FY2026 encounters and can be used directly for reimbursement purposes when supported by appropriate clinical documentation.
What drugs can cause osteomalacia in adults?
Anticonvulsants (phenytoin, phenobarbital, carbamazepine) are the most commonly implicated drug class, followed by tenofovir disoproxil fumarate, long-term high-dose aluminum-containing antacids, cholestyramine, and corticosteroids. Each acts through a distinct mechanism: anticonvulsants accelerate vitamin D catabolism, tenofovir causes phosphate wasting, and aluminum antacids bind dietary phosphate in the gut.
What documentation is required to use ICD-10 code M83.5?
The record must link the named causative drug to the osteomalacia diagnosis in the physician’s own words. It also needs supporting labs, such as low vitamin D, hypophosphatemia, or elevated alkaline phosphatase. Add a prescribing history with the drug name and duration, plus confirmation that the patient is 15 or older.
