2026 ICD-10-CM Diagnosis Code T38.896AUnderdosing of other hormones and synthetic substitutes, initial encounter
T38.896A is a billable ICD-10-CM diagnosis code for underdosing of other hormones and synthetic substitutes, initial encounter. The 7th character A marks it as an initial encounter code, used while the patient is receiving active treatment. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). The code is not accepted as a principal diagnosis by the Medicare Code Editor. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Underdosing of drugs and medicaments, initial encounter.
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for T38.896A.
Coding GuidelinesGuidance
Underdosing refers to taking less of a medication than is prescribed by a provider or a manufacturer's instruction. Codes for underdosing should never be assigned as principal or first-listed codes. If a patient has a relapse or exacerbation of the medical condition for which the drug is prescribed because of the reduction in dose, then the medical condition itself should be coded.
The appropriate 7th character is to be added to each code from block Poisoning by, adverse effect of and underdosing of hormones and their synthetic substitutes and antagonists, not elsewhere classified (T38). 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
Buserelin
a potent synthetic analog of gonadotropin-releasing hormone with d-serine substitution at residue 6, glycine10 deletion, and other modifications.Chorionic Gonadotropin
a gonadotropic glycoprotein hormone produced primarily by the placenta. similar to the pituitary luteinizing hormone in structure and function, chorionic gonadotropin is involved in maintaining the corpus luteum during pregnancy. cg consists of two noncovalently linked subunits, alpha and beta. within a species, the alpha subunit is virtually identical to the alpha subunits of the three pituitary glycoprotein hormones (tsh, lh, and fsh), but the beta subunit is unique and confers its biological specificity (chorionic gonadotropin, beta subunit, human).Chorionic Gonadotropin, beta Subunit, Human
the beta subunit of human chorionic gonadotropin. its structure is similar to the beta subunit of luteinizing hormone, except for the additional 30 amino acids at the carboxy end with the associated carbohydrate residues. hcg-beta is used as a diagnostic marker for early detection of pregnancy, spontaneous abortion (abortion, spontaneous); ectopic pregnancy; hydatidiform mole; choriocarcinoma; or down syndrome.Glycoprotein Hormones, alpha Subunit
the alpha chain of pituitary glycoprotein hormones (thyrotropin; follicle stimulating hormone; luteinizing hormone) and the placental chorionic gonadotropin. within a species, the alpha subunits of these four hormones are identical; the distinct functional characteristics of these glycoprotein hormones are determined by the unique beta subunits. both subunits, the non-covalently bound heterodimers, are required for full biologic activity.Receptors, LH
those protein complexes or molecular sites on the surfaces and cytoplasm of gonadal cells that bind luteinizing or chorionic gonadotropic hormones and thereby cause the gonadal cells to synthesize and secrete sex steroids. the hormone-receptor complex is internalized from the plasma membrane and initiates steroid synthesis.Felypressin
a synthetic analog of lypressin with a phenylalanine substitution at residue 2. felypressin is a vasoconstrictor with reduced antidiuretic activity.Leuprolide
a potent synthetic long-acting agonist of gonadotropin-releasing hormone that regulates the synthesis and release of pituitary gonadotropins, luteinizing hormone and follicle stimulating hormone.Lypressin
the porcine antidiuretic hormone (vasopressins). it is a cyclic nonapeptide that differs from arg-vasopressin by one amino acid, containing a lysine at residue 8 instead of an arginine. lys-vasopressin is used to treat diabetes insipidus or to improve vasomotor tone and blood pressure.Sermorelin
the biologically active fragment of human growth hormone-releasing factor, consisting of ghrh(1-29)-amide. this n-terminal sequence is identical in several mammalian species, such as human, pig, and cattle. it is used to diagnose or treat patients with growth hormone deficiency.Terlipressin
an inactive peptide prodrug that is slowly converted in the body to lypressin. it is used to control bleeding of esophageal varices and for the treatment of hepatorenal syndrome.
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
Hormones
Hormones are your body's chemical messengers. They travel in your bloodstream to tissues or organs. They work slowly, over time, and affect many different processes, including:
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert T38.896A to ICD-9-CMHistory
Code HistoryHistory
Questions About T38.896AOverview
Is T38.896A (Underdosing of other hormones and synthetic substitutes) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report underdosing of other hormones and synthetic substitutes, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in T38.896A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for underdosing of other hormones and synthetic substitutes, such as an emergency visit or first evaluation.
Can T38.896A be a principal diagnosis?
No. The Medicare Code Editor rejects this code as a principal diagnosis because underdosing of other hormones and synthetic substitutes, initial encounter describes a circumstance that influences health status rather than a current illness. Report it as a secondary diagnosis.
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.
