ICD-10-CM T43.636 is the diagnosis code for Underdosing of methylphenidate. This code falls under the section "Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances" within Chapter 19 — Injury, poisoning and certain other consequences of external causes (S00-T88). It is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes. Medical coders and healthcare providers use this code to document and classify diagnoses in electronic health records, insurance claims, and clinical databases.
Always refer to the official ICD-10-CM Tabular List for complete coding guidelines. Ensure documentation supports the specificity of the code selected. When in doubt, consult a certified medical coder or the latest CMS guidelines.
Understanding where T43.636 sits in the ICD-10-CM classification helps ensure proper coding:
Yes, T43.636 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
T43.636 is the ICD-10-CM diagnosis code for "Underdosing of methylphenidate". It is used by healthcare providers to classify and document this condition in medical records and insurance claims.
The parent code of T43.636 is T43.63 ("Poisoning by, adverse effect of and underdosing of methylphenidate"). T43.636 provides a more specific classification within this category.
T43.636 is located in Section T36-T50 — "Poisoning by, adverse effect of and underdosing of drugs, medicaments and biological substances" within Chapter 19 of the ICD-10-CM Tabular List.
Use T43.636 when the patients documented diagnosis matches "Underdosing of methylphenidate" and the clinical documentation supports this level of specificity. Always verify with the latest ICD-10-CM guidelines and payer requirements.
The ICD-10-CM code for Underdosing of methylphenidate is T43.636.
Yes, T43.636 can be used as a primary diagnosis code since it is billable and specific.
T43.636 is in Chapter 19 of the ICD-10-CM Tabular List.
Yes, T43.636 is a valid ICD-10-CM code for the 2026 fiscal year, subject to official CMS updates.