T40.424A ICD-10-CM Code: Poisoning by tramadol, undetermined, initial encounter

T40.424A is the ICD-10-CM diagnosis code for poisoning by tramadol, undetermined, initial encounter. T40.424A sits in the ICD-10-CM chapter for injury, poisoning and certain other consequences of external causes (s00-t88), within the section covering poisoning by, adverse effects of and underdosing of drugs, medicaments and biological substances (t36-t50).

Under the CMS-HCC V28 risk adjustment model, T40.424A maps to Drug Use Disorder, Moderate/Severe, or Drug Use with Non-Psychotic Complications (HCC 137) with a source-labeled community, non-dual, aged reference coefficient of 0.424. For CY2026 non-PACE Medicare Advantage, CMS uses 100% of the 2024 CMS-HCC model (V28). PACE uses a separate model blend. Source-labeled code-level coefficients are references, not member totals. Actual contribution depends on complete member context, hierarchy and cleanup rules, interactions, and model year. HCC Buddy's RAF Calculator supports CMS-HCC V28 PY2026 and shows no score unless every required source and calculation check passes.

Coders should report T40.424A only when the provider documentation supports the specific condition described, since more specific codes within the same hierarchy can capture additional clinical detail. For T40.424A, confirm that the documentation supports the diagnosis and meets the applicable coding, encounter, program and payer requirements. MEAT (Monitor, Evaluate, Assess, or Treat) is a review mnemonic, not a universal CMS coding rule. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.