2026 ICD-10-CM Diagnosis Code T47.6X6AUnderdosing of antidiarrheal drugs, initial encounter
T47.6X6A is a billable ICD-10-CM diagnosis code for underdosing of antidiarrheal drugs, 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 T47.6X6A.
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 agents primarily affecting the gastrointestinal system (T47). 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
1,4-alpha-Glucan Branching Enzyme
in glycogen or amylopectin synthesis, the enzyme that catalyzes the transfer of a segment of a 1,4-alpha-glucan chain to a primary hydroxy group in a similar glucan chain. ec 2.4.1.18.Amylopectin
a highly branched glucan in starch.Glycogen Storage Disease Type IV
an autosomal recessive metabolic disorder due to a deficiency in expression of glycogen branching enzyme 1 (alpha-1,4-glucan-6-alpha-glucosyltransferase), resulting in an accumulation of abnormal glycogen with long outer branches. clinical features are muscle hypotonia and cirrhosis. death from liver disease usually occurs before age 2.Charcoal
an amorphous form of carbon prepared from the incomplete combustion of animal or vegetable matter, e.g., wood. the activated form of charcoal is used in the treatment of poisoning. (grant & hackh's chemical dictionary, 5th ed)Diphenoxylate
a meperidine congener used as an antidiarrheal, usually in combination with atropine. at high doses, it acts like morphine. its unesterified metabolite difenoxin has similar properties and is used similarly. it has little or no analgesic activity.Kaolin
the most common mineral of a group of hydrated aluminum silicates, approximately h2al2si2o8-h2o. it is prepared for pharmaceutical and medicinal purposes by levigating with water to remove sand, etc. (from merck index, 11th ed) the name is derived from kao-ling (chinese: high ridge), the original site. (from grant & hackh's chemical dictionary, 5th ed)Partial Thromboplastin Time
the time required for the appearance of fibrin strands following the mixing of plasma with phospholipid platelet substitute (e.g., crude cephalins, soybean phosphatides). it is a test of the intrinsic pathway (factors viii, ix, xi, and xii) and the common pathway (fibrinogen, prothrombin, factors v and x) of blood coagulation. it is used as a screening test and to monitor heparin therapy.Bacillus coagulans
a microaerophilic, lactic acid producing species of bacillus that occurs in fermented foods. it also produces anti-infective agents and is used as a probiotic.Lacticaseibacillus casei
a rod-shaped bacterium isolated from milk and cheese, dairy products and dairy environments, sour dough, cow dung, silage, and human mouth, human intestinal contents and stools, and the human vagina. l. casei is catalase positive.Lacticaseibacillus paracasei
a species of lacticaseibacillus that occurs in the gut microbiota of healthy humans as well as fermented dairy products and fermented vegetables. it is used as a probiotic.Lacticaseibacillus rhamnosus
a species of gram-positive, rod-shaped bacteria used in probiotics.Lactobacillus
a genus of gram-positive, microaerophilic, rod-shaped bacteria occurring widely in nature. its species are also part of the many normal flora of the mouth, intestinal tract, and vagina of many mammals, including humans. lactobacillus species are homofermentative and ferment a broad spectrum of carbohydrates often host-adapted but do not ferment pentoses. most members were previously assigned to the lactobacillus delbrueckii group. pathogenicity from this genus is rare.Lactobacillus acidophilus
a species of gram-positive, rod-shaped bacteria isolated from the intestinal tract of humans and animals, the human mouth, and vagina. this organism produces the fermented product, acidophilus milk.Lactobacillus crispatus
a species of lactobacillus that occurs in the human gastrointestinal tract and the vagina of healthy women. it produces lactic acid and hydrogen peroxide, and is used as a probiotic. it is also used for the treatment and prevention of bacterial vaginosis.Lactobacillus delbrueckii
a species of gram-positive, rod-shaped, facultatively anaerobic bacteria. capable of producing lactic acid. it is important in the manufacture of fermented dairy products.Lactobacillus gasseri
a species of lactobacillus that occurs in the human oral mucosa; gastrointestinal tract; and vagina. it produces bacteriocins, can modulate the immune response, and is used as a probiotic.Lactobacillus helveticus
a species of gram-positive bacteria isolated from milk and cheese-starter cultures.Lactobacillus johnsonii
a species of lactobacillus that occurs in the human gastrointestinal tract and vagina. it produces bacteriocins and hydrogen peroxide and is used as a probiotic.Lactobacillus leichmannii
a species of gram-negative bacteria isolated from milk, cheese, and compressed yeast.Lactobacillus pentosus
a species of lactobacillus that occurs in fermented foods where its ability to produce lactic acid; anti-infective agents; and bacteriocins make it useful as a food preservation agent. it is also used as a probiotic.Lactobacillus plantarum
a species of rod-shaped, lactic acid bacteria used in probiotics and silage production.Latilactobacillus sakei
a species of lactobacillus that occurs in fermented meat and fish. it produces the bacteriocin sakacin p and is used for food preservation and as a probiotic.Levilactobacillus brevis
a species of gram-positive, rod-shaped lactic acid bacteria that is frequently used as starter culture in silage fermentation, sourdough, and lactic-acid-fermented types of beer and wine.Ligilactobacillus salivarius
a species of lactobacillus that occurs in the human gastrointestinal tract and oral mucosa. it produces bacteriocins and is used as a probiotic.Limosilactobacillus fermentum
a species of gram-positive, rod-shaped bacteria associated with dental caries.Limosilactobacillus reuteri
a species of gram-positive, rod-shaped lactic acid bacteria found naturally in the human intestinal flora and breast milk.Loperamide
one of the long-acting synthetic antidiarrheals; it is not significantly absorbed from the gut, and has no effect on the adrenergic system or central nervous system, but may antagonize histamine and interfere with acetylcholine release locally.Saccharomyces boulardii
a species of saccharomyces that is used as a probiotic, such as in the treatment of diarrhea and pseudomembranous enterocolitis associated with clostridium infections.
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.
| Substance | Accidental | Self-harm | Assault | Undetermined | Adverse Effect | Underdosing |
|---|---|---|---|---|---|---|
| Activated charcoal [See Also: Charcoal, medicinal] | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Amylopectin | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Antidiarrheal drug NEC | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Antidiarrheal drug NEC::absorbent | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Attapulgite | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Bismuth salts | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Bismuth salts::aluminate | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Bismuth salts::anti-infectives | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Bismuth salts::formic iodide | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Bismuth salts::glycolylarsenate | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Bismuth salts::nonmedicinal (compounds) NEC | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Bismuth salts::subcarbonate | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Bismuth salts::subsalicylate | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Bismuth salts::sulfarsphenamine | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Carbo medicinalis | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Charcoal | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Charcoal::activated [See Also: Charcoal, medicinal] | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Charcoal::fumes (Carbon monoxide) | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Charcoal::fumes (Carbon monoxide)::industrial | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Charcoal::medicinal (activated) | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Charcoal::medicinal (activated)::antidiarrheal | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Charcoal::medicinal (activated)::poison control | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Charcoal::medicinal (activated)::specified use other than for diarrhea | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Charcoal::medicinal (activated)::topical | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Difenoxin | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Diphenoxylate | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Fetoxilate | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Intestinal motility control drug | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Intestinal motility control drug::biological | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Kaolin | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Kaolin::light | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Lactobacillus | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Lactobacillus::acidophilus | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Lactobacillus::acidophilus::compound | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Lactobacillus::bifidus, lyophilized | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Lactobacillus::bulgaricus | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Lactobacillus::sporogenes | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Lignin hemicellulose | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Lomotil | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Loperamide | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Miyari bacteria | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Pectin | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
| Saccharomyces boulardii | T47.6X1 | T47.6X2 | T47.6X3 | T47.6X4 | T47.6X5 | T47.6X6 |
Patient EducationClinical
Medication Errors
Medicines treat infectious diseases, prevent problems from chronic diseases, and ease pain. But medicines can also cause harmful reactions if not used correctly. Errors can happen in the hospital, at the health care provider's office, at the pharmacy, or at home. You can help prevent errors by:
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert T47.6X6A to ICD-9-CMHistory
Code HistoryHistory
Questions About T47.6X6AOverview
Is T47.6X6A (Underdosing of antidiarrheal drugs) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report underdosing of antidiarrheal drugs, initial encounter on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
What does the 7th character A in T47.6X6A mean?
The final character A marks the initial encounter: use it while the patient is receiving active treatment for underdosing of antidiarrheal drugs, such as an emergency visit or first evaluation.
Can T47.6X6A be a principal diagnosis?
No. The Medicare Code Editor rejects this code as a principal diagnosis because underdosing of antidiarrheal drugs, 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.
