2026 ICD-10-CM Diagnosis Code T36.3X1SPoisoning by macrolides, accidental (unintentional), sequela
T36.3X1S is a billable ICD-10-CM diagnosis code for poisoning by macrolides, accidental (unintentional), sequela. The 7th character S marks it as a sequela code, which reports a problem that remains after the original condition has resolved. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026) and groups to MS-DRG 922 through 923. The code is exempt from POA reporting. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Poisoning/toxic effect/adverse effects/underdosing, sequela.
Code Identity
Code Classification
Present on Admission (POA)Billing
T36.3X1S is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Accidental azithromycin overdose
- Accidental azithromycin poisoning
- Accidental clarithromycin overdose
- Accidental clarithromycin poisoning
- Accidental erythromycin overdose
- Accidental erythromycin poisoning
- Accidental oleandomycin poisoning
- Accidental spiramycin poisoning
- Azithromycin overdose
- Azithromycin poisoning
- Clarithromycin overdose
- Clarithromycin poisoning
- Erythromycin overdose
- Erythromycin poisoning
- Macrolide antibacterial overdose
- Poisoning by macrolide
- Poisoning by oleandomycin
- Poisoning by spiramycin
Coding GuidelinesGuidance
When coding a poisoning or reaction to the improper use of a medication (e.g., overdose, wrong substance given or taken in error, wrong route of administration), first assign the appropriate code from categories T36-T50. The poisoning codes have an associated intent as their 5th or 6th character (accidental, intentional self-harm, assault and undetermined). If the intent of the poisoning is unknown or unspecified, code the intent as accidental intent. The undetermined intent is only for use if the documentation in the record specifies that the intent cannot be determined. Use additional code(s) for all manifestations of poisonings.
The appropriate 7th character is to be added to each code from block Poisoning by, adverse effect of and underdosing of systemic antibiotics (T36). Use the following options for the applicable episode of care:
- A - initial encounter
- D - subsequent encounter
- S - sequela
Source: ICD-10-CM Official Guidelines for Coding and Reporting, FY 2026, published by CMS and the National Center for Health Statistics.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Azithromycin
a semi-synthetic macrolide antibiotic structurally related to erythromycin. it has been used in the treatment of mycobacterium avium intracellulare infections, toxoplasmosis, and cryptosporidiosis.Josamycin
a macrolide antibiotic from streptomyces narbonensis. the drug has antimicrobial activity against a wide spectrum of pathogens.Kitasamycin
a macrolide antibiotic produced by streptomyces kitasatoensis. the drug has antimicrobial activity against a wide spectrum of pathogens.Oleandomycin
antibiotic macrolide produced by streptomyces antibioticus.Pristinamycin
an antibiotic mixture originally isolated from streptomyces pristinaspiralis. it is a mixture of compounds from streptogramin group a: pristinamycin iia and iib and from streptogramin group b: pristinamycin ia, pristinamycin ib, pristinamycin ic.Streptogramin A
a specific streptogramin group a antibiotic produced by streptomyces graminofaciens and other bacteria.Streptogramin B
a specific streptogramin group b antibiotic produced by streptomyces graminofaciens and other bacteria.Roxithromycin
semisynthetic derivative of erythromycin. it is concentrated by human phagocytes and is bioactive intracellularly. while the drug is active against a wide spectrum of pathogens, it is particularly effective in the treatment of respiratory and genital tract infections.Spiramycin
a macrolide antibiotic produced by streptomyces ambofaciens. the drug is effective against gram-positive aerobic pathogens, n. gonorrhoeae, and staphylococci. it is used to treat infections caused by bacteria and toxoplasma gondii.Troleandomycin
a macrolide antibiotic that is similar to erythromycin.
Table of Drugs and ChemicalsClinical
Substances in the Table of Drugs and Chemicals that reference this code family. Always confirm in the Tabular List before coding.
Patient EducationClinical
Antibiotics
Antibiotics are medicines that fight bacterial infections in people and animals. They work by killing the bacteria or by making it hard for the bacteria to grow and multiply.
The full article covers:
- What are antibiotics?
- What do antibiotics treat?
- Do antibiotics treat viral infections?
- What are the side effects of antibiotics?
- Why is it important to take antibiotics only when they're needed?
- How do I use antibiotics correctly?
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert T36.3X1S to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T36.3X1SOverview
Is T36.3X1S (Poisoning by macrolides, accidental (unintentional)) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report poisoning by macrolides, accidental (unintentional), sequela on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character S in T36.3X1S mean?
The final character S makes this a sequela code: it reports a lingering problem that remains after the poisoning by macrolides, accidental (unintentional) itself has resolved, not the original event.
What MS-DRG does T36.3X1S group to?
When poisoning by macrolides, accidental (unintentional), sequela is the principal diagnosis on an inpatient stay, it groups to MS-DRG 922, 923, with relative weights from 1.0177 to 1.7494 depending on complications. Higher weights mean higher Medicare reimbursement.
Is T36.3X1S exempt from POA reporting?
Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for poisoning by macrolides, accidental (unintentional), sequela on inpatient claims.
What is the ICD-9 equivalent of T36.3X1S?
Under the General Equivalence Mappings, poisoning by macrolides, accidental (unintentional), sequela converts to ICD-9-CM 909.0 (late eff drug poisoning) and E929.2 (late eff acc poisoning). The mapping is approximate, so confirm the match fits the documentation.
Footnotes
[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.
