T50.99Header code — not billable

Poisoning by, adverse effect of and underdosing of other drugs, medicaments and biological substances

Short description: Drugs, medicaments and biological substances

Chapter
19. Injury, poisoning and certain other consequences of external causes
Category
T50
Effective date
October 1, 2026

Related codes in category T50

T50Diuretics and oth and unsp drug/meds/biol substT50.0Mineralocorticoids and their antagonistsT50.0XMineralocorticoids and their antagonistsT50.0X1Poisoning by mineralocorticoids and their antag, accidentalT50.0X1APoisoning by mineralocorticoids and their antag, acc, initYesT50.0X1DPoisoning by mineralocorticoids and their antag, acc, subsYesT50.0X1SPoisoning by mineralocorticoids and antag, acc, sequelaYesT50.0X2Poisoning by mineralocorticoids and their antag, self-harmT50.0X2APoisoning by mineralocorticoids and antag, self-harm, initYesT50.0X2DPoisoning by mineralocorticoids and antag, self-harm, subsYesT50.0X2SPoisn by mineralocorticoids and antag, self-harm, sequelaYesT50.0X3Poisoning by mineralocorticoids and their antag, assault

Frequently asked questions

What is ICD-10 code T50.99?

T50.99 is an ICD-10-CM diagnosis code for Poisoning by, adverse effect of and underdosing of other drugs, medicaments and biological substances.

Is T50.99 a billable code?

No. T50.99 is a category/header code, not billable on its own — use one of its more specific child codes instead.

What ICD-10-CM chapter is T50.99 in?

T50.99 falls under Chapter 19: Injury, poisoning and certain other consequences of external causes.

When did T50.99 become effective?

T50.99 has been effective since October 1, 2026, per the CMS/CDC ICD-10-CM annual release.

What other codes are related to T50.99?

T50.99 belongs to category T50, which includes 12 other codes — see the related codes list on this page.

ICD-10-CM data maintained by CDC/CMS (public domain). Always verify codes with authoritative sources before making coding or billing decisions.