2026 ICD-10-CM Diagnosis Code T37.4X3SPoisoning by anthelminthics, assault, sequela
T37.4X3S is a billable ICD-10-CM diagnosis code for poisoning by anthelminthics, assault, 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
T37.4X3S is exempt from POA reporting on inpatient claims to general acute care hospitals. Review other POA exempt codes.
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 other systemic anti-infectives and antiparasitics (T37). 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
Albendazole
a benzimidazole broad-spectrum anthelmintic structurally related to mebendazole that is effective against many diseases. (from martindale, the extra pharmacopoeia, 30th ed, p38)Chenopodium
a plant genus in the chenopodiaceae family.Chenopodium album
a plant species in the chenopodium genus known for edible greens.Chenopodium ambrosioides
a plant species of the genus chenopodium known for toxicity to intestinal worms and other simple organisms.Chenopodium quinoa
a species of the chenopodium genus which is the source of edible seed called quinoa. it contains makisterone a and other steroids, some having ecdysteroid activity on insects.2,6-Dichloroindophenol
a dye used as a reagent in the determination of vitamin c.Dichlorophen
nontoxic laxative vermicide effective for taenia infestation. it tends to produce colic and nausea. it is also used as a veterinary fungicide, anthelmintic, and antiprotozoan. (from merck, 11th ed.)Diethylcarbamazine
an anthelmintic used primarily as the citrate in the treatment of filariasis, particularly infestations with wucheria bancrofti or loa loa.Fenbendazole
antinematodal benzimidazole used in veterinary medicine.Ivermectin
a mixture of mostly avermectin h2b1a (rn 71827-03-7) with some avermectin h2b1b (rn 70209-81-3), which are macrolides from streptomyces avermitilis. it binds glutamate-gated chloride channel to cause increased permeability and hyperpolarization of nerve and muscle cells. it also interacts with other chloride channels. it is a broad spectrum antiparasitic that is active against microfilariae of onchocerca volvulus but not the adult form.Levamisole
an antihelminthic drug that has been tried experimentally in rheumatic disorders where it apparently restores the immune response by increasing macrophage chemotaxis and t-lymphocyte function. paradoxically, this immune enhancement appears to be beneficial in rheumatoid arthritis where dermatitis, leukopenia, and thrombocytopenia, and nausea and vomiting have been reported as side effects. (from smith and reynard, textbook of pharmacology, 1991, p435-6)Lucanthone
one of the schistosomicides, it has been replaced largely by hycanthone and more recently praziquantel. (from martindale the extrapharmacopoeia, 30th ed., p46)Mebendazole
a benzimidazole that acts by interfering with carbohydrate metabolism and inhibiting polymerization of microtubules.Niclosamide
an antihelmintic that is active against most tapeworms. (from martindale, the extra pharmacopoeia, 30th ed, p48)Niridazole
an antischistosomal agent that has become obsolete.Oxamniquine
an anthelmintic with schistosomicidal activity against schistosoma mansoni, but not against other schistosoma spp. oxamniquine causes worms to shift from the mesenteric veins to the liver where the male worms are retained; the female worms return to the mesentery, but can no longer release eggs. (from martindale, the extra pharmacopoeia, 31st ed, p121)Diketopiperazines
piperazines with two keto oxygens.Piperazine
an anti-nematodal agent effective against the intestinal nematodes ascaris lumbricoides (roundworm) and enterobius vermicularis (pinworm, threadworm). it produces a neuromuscular block leading to flaccid muscle paralysis in susceptible worms, which are then dislodged from the gut and expelled in feces.Piperazines
compounds that are derived from piperazine.Praziquantel
an anthelmintic used in most schistosome and many cestode infestations.Pyrantel
a depolarizing neuromuscular-blocking agent, that causes persistent nicotinic activation resulting in spastic paralysis of susceptible nematodes. it is a drug of second-choice after benzimidazoles for treatment of ascariasis, hookworm, and pinworm infections, being effective after a single dose. (from smith and reynard, textbook of pharmacology, 1992, p920)Pyrantel Pamoate
broad spectrum antinematodal anthelmintic used also in veterinary medicine.Pyrantel Tartrate
broad spectrum anthelmintic for livestock.Santonin
anthelmintic isolated from the dried unexpanded flower heads of artemisia maritima and other species of artemisia found principally in russian and chinese turkestan and the southern ural region. (from merck, 11th ed.)Tetramisole
used in the form of the hydrochloride as a reagent in analytical chemistry techniques.Thiabendazole
2-substituted benzimidazole first introduced in 1962. it is active against a variety of nematodes and is the drug of choice for strongyloidiasis. it has central nervous system side effects and hepatototoxic potential. (from smith and reynard, textbook of pharmacology, 1992, p919)
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
Poisoning
A poison is any substance that is harmful to your body. You might swallow it, inhale it, inject it, or absorb it through your skin. Any substance can be poisonous if too much is taken. Poisons can include:
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert T37.4X3S to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About T37.4X3SOverview
Is T37.4X3S (Poisoning by anthelminthics, assault) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report poisoning by anthelminthics, assault, sequela on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character S in T37.4X3S mean?
The final character S makes this a sequela code: it reports a lingering problem that remains after the poisoning by anthelminthics, assault itself has resolved, not the original event.
What MS-DRG does T37.4X3S group to?
When poisoning by anthelminthics, assault, 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 T37.4X3S 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 anthelminthics, assault, sequela on inpatient claims.
What is the ICD-9 equivalent of T37.4X3S?
Under the General Equivalence Mappings, poisoning by anthelminthics, assault, sequela converts to ICD-9-CM 909.0 (late eff drug poisoning) and E969 (late effect assault). 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.
