Keri

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Keri

Treatment option: Gastritis, Diarrhea

Medically reviewed

Marina Burgos

Last updated on 10/01/2026

This page provides general, reference-level information compiled from official medical sources. It is not a substitute for professional medical advice, diagnosis, or treatment. For decisions about your health, please consult a qualified healthcare professional.

Overview of Keri

What is Keri? (Nifuroxazide)

Property Description
Active ingredient Nifuroxazide
Form Oral tablet, Capsule, Oral Suspension
Pharmacological class Intestinal Antiseptic, Antimicrobial Agent
General purpose Targeted control of susceptible intestinal bacteria
Origin Synthetic Compound (5-nitrofuran derivative)

What Type of Medicine is Keri (Nifuroxazide)?

Keri is a synthetic, single-ingredient medicine classified primarily as an intestinal antiseptic and a non-systemic antimicrobial agent. The active substance is Nifuroxazide, a compound that chemically belongs to the distinct group of 5-nitrofuran derivatives, classified as a synthetic organic compound. This classification emphasizes its specific utility: it is designed to address acute gastrointestinal infections, representing a strategy to resolve the microbial imbalance associated with acute diarrhea. Its non-systemic nature is a distinguishing feature, recognized for concentrating the antimicrobial effect specifically within the gastrointestinal tract, minimizing systemic exposure.


Composition and Available Forms of Keri

The core composition of Keri consists of the single active substance, Nifuroxazide, formulated with necessary pharmaceutical excipients. As a medication intended for a broad patient group, Nifuroxazide is commonly available for ingestion in multiple pharmaceutical forms, including the oral tablet, capsule, and various forms of oral suspension. The availability of an oral suspension is a key feature that facilitates administration to younger patients, offering a tailored option beyond solid-dose forms. The drug's non-absorbable nature ensures it exerts its effect directly in the intestine before excretion.


What is the General Purpose of Keri?

The general purpose of Keri is to provide a targeted solution for the microbial imbalances underlying acute gastrointestinal distress by functioning as a localized intestinal antiseptic. Its design enables it to deliver a concentrated antimicrobial effect directly at the site of infection within the gut. This specific mechanism aims to control or eliminate susceptible pathogenic bacteria, thereby addressing the root cause of common intestinal issues and supporting the restoration of normal digestive function, which is the primary therapeutic goal for patients experiencing acute, infectious-related diarrhea.

What side effects are possible with Keri?

Possible Side Effects and Safety Information

The safety profile of Keri (Nifuroxazide), as documented in official regulatory sources, primarily involves localized gastrointestinal effects and the potential for hypersensitivity reactions. Consistent with its classification as a non-systemic intestinal antiseptic, safety considerations focus on reactions within the gut and immune responses.


Officially Documented Adverse Reactions

The majority of adverse reactions reported are classified with a frequency of "not known" (incidence cannot be estimated from available data), as they are largely based on post-marketing surveillance. These reported effects are typically grouped by the following systems:

System-Organ Class Examples of Reactions Official Frequency Classification
Immune System Disorders Anaphylactic shock, Angioedema, Allergic reactions Not known
Skin and Subcutaneous Tissue Rash, Pruritus (itching), Urticaria (hives) Not known
Gastrointestinal Disorders Abdominal pain, Nausea, Vomiting Not known

Serious Adverse Reactions and Safety Constraints

Official labeling highlights the possibility of serious adverse reactions, particularly severe hypersensitivity events such as anaphylactic shock and angioedema (swelling of the face, lips, or throat).

The medication is contraindicated in individuals with a history of hypersensitivity to Nifuroxazide or other nitrofuran derivatives.


Population-Specific Safety Considerations

The regulatory profile includes specific restrictions for vulnerable groups:

  • Infants: The use of Nifuroxazide is contraindicated in infants younger than two months of age.
  • Pregnancy and Lactation: As a precaution, the medicine should not be used during pregnancy due to regulatory concerns regarding potential mutagenic effects observed in non-clinical studies. Similar precautionary advice applies during breastfeeding, although short-term use may be possible under specific clinical guidance.

Overdose and Emergency Response

Overdose and When to Seek Help for Keri (Nifuroxazide)

This section provides the officially documented overdose information as presented by regulatory authorities, strictly avoiding general medical advice or interpretation. Keri, known chemically as Nifuroxazide, is classified as an intestinal antiseptic with poor systemic absorption, a property which influences the official statements regarding an overdose event and clinical outcomes.

Documented Overdose Profile

Manifestation Official Regulatory Finding
Specific Symptoms No specific clinical data are available in the regulatory documentation detailing the characteristic signs or symptoms resulting from an overdose of Nifuroxazide.
Severe Outcomes The official overdose information does not formally document any specific severe or life-threatening manifestations.
Specific Antidote No specific antidote is explicitly mentioned in the official labeling for the management of an overdose.
Specific Procedures The regulatory text does not explicitly detail supportive procedures such as gastric lavage or the use of activated charcoal.

When Urgent Medical Help is Required

Regulatory authorities mandate that immediate medical attention must be sought in the event of any suspected ingestion of an amount exceeding the prescribed or recommended dose. This instruction is necessary, as there are no characteristic clinical effects specified in the official profile. The overall overdose structure is thus defined by the absence of specific documented clinical data, necessitating the universal regulatory action of seeking urgent professional evaluation for overexposure.


Therapeutic Uses of Keri

Keri (Nifuroxazide) is generally used across therapeutic domains where short-term symptomatic assistance is needed to manage acute gastrointestinal issues. Its application is considered relevant in clinical settings that involve acute or unstable symptom patterns related to localized infection. The medication is commonly used for managing acute diarrheal episodes associated with a presumed bacterial cause, including presentations like traveler's diarrhea and non-complicated acute gastroenteritis. This focus is on conditions where symptoms of heightened physiological activity and discomfort are linked to a microbial issue within the gut. Nifuroxazide is categorized as an anti-infective agent for intestinal use.

Keri is applied in addressing symptom clusters that may become intense or disruptive, such as frequent, loose, or watery stools that interfere with daily functioning. The use is relevant for easing symptoms associated with a localized microbial issue, and may support a reduction in the overall burden of distressing manifestations. This may assist with maintaining a sense of stability during episodes of temporary physiological imbalance.

Quick Fact: Symptomatic Relief for Acute Diarrhea

Keri is applied in scenarios where additional management of discomfort is required, contributing to improved comfort during periods of heightened symptoms. It supports the patient during difficult episodes by easing distress and is applied in addressing conditions marked by increased physiological stress.

Eligibility and Restrictions for Use

Keri (Nifuroxazide) is subject to strict eligibility rules documented in official regulatory labeling, primarily concerning age, pre-existing conditions, and physiological state. The medicine is generally established for use in adults and children over 3 months of age.

Contraindications and Restrictions

Classification Population/Condition Restriction Statement (Official Basis)
Absolute Contraindication Infants younger than 3 months old Must not be administered (no clinical trials in this population).
Absolute Contraindication Known Hypersensitivity Contraindicated due to allergy to Nifuroxazide or excipients.
Prohibited Use Children with pre-existing Renal or Hepatic Impairment Must not be administered (lack of study data in this sub-population).
Not Recommended Pregnant Women Should not be given as a precaution (based on possible mutagenic potential).
Conditional Use Breastfeeding Women Use is possible only in case of short-term treatment.

Older adults are generally eligible for use, but caution is advised due to the potential for age-related changes in organ function. Caution is also advised for all adults with existing hepatic or renal impairment.

What should I know about interactions with other medicines?

Interactions with other medicines and products

The official regulatory profile for Keri (Nifuroxazide) is defined by its non-systemic nature, which results in a limited potential for drug-drug interactions compared to systemically absorbed medicines.

Interaction Scope and Restrictions

Category Official Regulatory Information
Medicinal products with negligible systemic risk The potential for clinically relevant interactions with medicines that are substrates for CYP enzymes or drug transporters is considered negligible.
Specific interacting substance Alcohol (Ethanol) is formally documented as a strictly contraindicated substance.
Interaction-related restrictions Co-administration with alcohol is prohibited due to the risk of triggering a severe pharmacodynamic intolerance, specifically a disulfiram-like reaction.

Timing-Based Administration Rules

Category Official Regulatory Information
Product categories with timing rules Adsorbent substances (e.g., activated charcoal, kaolin) and agents that accelerate intestinal transit (certain laxatives).
Required constraint Administration of Nifuroxazide must be separated by a specific time window from adsorbent products or laxatives. This required separation is intended to prevent the reduction of the drug's effective local concentration within the intestinal lumen.

Connection to the Overall Interaction Profile

Regulatory documentation specifies that the drug’s interaction structure primarily focuses on ensuring adequate local antimicrobial exposure and strictly prohibiting the use of alcohol. The absence of significant systemic absorption is the regulatory basis for the negligible concern regarding most metabolic or transporter-mediated drug interactions.

Mechanism of Action

The mechanism of Keri relies on highly specific bacterial nitroreductase enzymes to activate the drug. Once inside the susceptible bacterial cell, these enzymes convert the molecule into highly reactive intermediate species. This essential bio-activation process confines the antimicrobial effect to the gastrointestinal lumen, the primary site of microbial colonization.


The short-lived, reactive intermediates formed upon activation immediately cause irreversible damage to the bacteria's essential structures, including their DNA, RNA, and vital metabolic enzymes. This simultaneous, multi-point attack halts cellular replication and synthesis, resulting in the inhibition of bacterial growth and a reduction of the susceptible microbial population within the intestinal lumen.


Because the drug is designed to be non-systemic, its mechanism remains confined to the gut, maintaining a high concentration within the gut lumen. The resulting reduction in the pathogenic microbial load directly lowers the release of bacterial toxins that drive host cells to engage in excessive fluid and electrolyte hypersecretion. This localized action contributes to the modulation of intestinal fluid transport, a key physiological change resulting from the antibacterial activity.

Dosage and Administration Information

Keri (Nifuroxazide) is administered exclusively via the oral route, consistent with its function as an intestinal antiseptic designed for non-systemic action. The medicine is commonly supplied in solid oral tablets or capsules (often 200 mg or 400 mg strengths) and as an oral suspension. The suspension form is specifically designated for use in pediatric populations to enable precise, weight- or age-based dose adjustment.


Administration and Regimen

The standard approach involves a divided daily regimen, requiring the total daily dose to be split into multiple administrations throughout the day. Typical adult dosing schedules involve taking a 200 mg unit dose four times daily or a 400 mg unit dose twice daily, which maintains a consistent concentration of the active substance within the gastrointestinal tract.

A key administration instruction is the requirement to take the medication with food or immediately following a meal. This contextual requirement is standardized in the use protocol.


Duration and Special Conditions

The required treatment duration is fixed and short-term, typically lasting 3 days to 5 days. The course should not exceed this period. For those using the liquid suspension, the bottle must be shaken well immediately before measuring the dose to ensure the correct concentration is administered. Solid forms, such as tablets, are intended to be swallowed whole. This structured protocol defines the procedural use of Nifuroxazide.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Keri (Nifuroxazide)

Evidence for Use in Acute Diarrhea

The regulatory review of Keri (Nifuroxazide) was studied for conditions characterized by fluctuating or episodic manifestations, particularly acute diarrhea presumed to be caused by bacteria. The research documentation available for this compound includes short-term Randomized Controlled Trials (RCTs) and systematic reviews. In these studies, research examined outcomes related to physical discomfort and outcomes describing episodic or acute changes in symptoms.

Findings sometimes indicate that patterns related to more rapid changes in stool frequency were observed in some studies compared to control groups, but the evidence quality varies across studies, and the synthesis of results shows some heterogeneity. The data are not always characterized relative to a confirmed causative pathogen.

Evidence for Use in Traveler's Diarrhea

Keri was evaluated in studies focused on the management of conditions associated with acute or disruptive episodes linked to travel. The research monitored patient-reported outcomes describing perceived discomfort and the proportion of participants who reached study-defined symptom resolution criteria over short, defined time intervals. Findings indicate patterns related to symptom resolution in this specialized group.

Long-Term Evidence and Follow-Up Duration

Most research studies exploring Keri (Nifuroxazide) are focused on the immediate, acute phase of illness. The research typically involves follow-up durations that were limited. As a result, long-term effects are not fully established. There is limited information for long-term outcomes such as durability of response or any effects on stability extending well beyond the acute episode.

Research in Specific Patient Groups

Data for certain groups remain insufficient. For instance, there is limited information about the research profile of Keri in older adults or in pregnant or breastfeeding individuals, as these groups are often excluded from the primary research documentation. The research provides context about group patterns but does not determine whether an individual will respond similarly.

Frequently Asked Questions (FAQ)

Common questions about Keri (FAQ)

Q: Is Keri considered a prescription-strength medicine or an over-the-counter product?

The legal classification of the active ingredient Nifuroxazide (Keri) is determined by the national drug regulatory authority where the product is sold. Its status may vary between being a prescription-only medicine and an over-the-counter (OTC) product depending on the specific country's regulations.

Q: Is the active ingredient in Keri common or unique compared to alternatives?

Official regulatory classifications indicate that the active ingredient, Nifuroxazide, belongs to a chemically distinct group known as the 5-nitrofuran derivatives. While it is classified as an intestinal anti-infective, its specific chemical structure places it in a different category than many common alternatives.

Q: What are the most common reported side effects of Keri?

Official regulatory documents list several adverse reactions, including abdominal pain, nausea, rash, and allergic reactions. However, the frequency of the majority of these reported side effects is classified as "not known," meaning there is insufficient data to estimate how often they occur in the general population.

Q: What are the signs of a non-serious versus a serious reaction to Keri?

Serious reactions explicitly noted in regulatory documents include severe hypersensitivity events such as anaphylactic shock and angioedema (swelling of the face, lips, or throat). Other reported reactions like nausea, vomiting, or rash are also noted in the safety summary.

Q: Is Keri usage different for older adults?

Official guidelines advise caution when used by older adults due to the potential for age-related changes in organ function, such as hepatic or renal impairment. No specific difference in the dosing regimen is detailed in the general regulatory summary.

Q: What is the status of research evidence for Keri's ingredients?

Regulatory research overviews primarily focus on the effectiveness and safety data of the active substance, Nifuroxazide. Information concerning the research status or function of non-active ingredients (excipients) used in the formulation is usually limited in these specific regulatory summaries.

Q: Does Keri expire, and what are the general storage conditions?

Official product information indicates that Keri has a fixed expiration date (shelf-life) printed on the original packaging. Additionally, the liquid oral suspension form has a limited in-use stability period once it is prepared or opened and should be stored according to specific instructions to help maintain its integrity.

Q: What does the term "for symptomatic relief" mean regarding Keri's use?

In the context of Keri’s intended use, the term symptomatic relief refers to reducing the acute physical symptoms of diarrhea, such as excessive stool frequency and fluid loss. This relief is described as resulting from the medicine's primary localized antimicrobial action against susceptible bacteria in the gut.

Q: What is the function of the main non-active ingredients in Keri?

Non-active ingredients (excipients) in Keri formulations, such as those used in tablets (e.g., starches, binders) or suspensions (e.g., sugars, thickeners), function to ensure the product's stability, provide the proper form, and assist in its administration.

Q: Does Keri contain alcohol or parabens?

The presence of specific ingredients like alcohol or parabens can only be confirmed by consulting the official composition label for the particular Keri formulation (tablet, capsule, or suspension) being used. The official documentation lists all components.

Q: Is Keri considered a fragrance-free product?

Regulatory documents list all ingredients used in the formulation, which includes any flavorings or odorants if they are present. While this information allows for checking if added fragrances are included, the product is not typically assigned the specific labeling term 'fragrance-free' by regulatory bodies.

Q: Does Keri contain lanolin, and is that a common allergen?

The presence of lanolin or any other specific excipient can only be confirmed by reviewing the official product labeling (Composition Section). Official contraindications state the product is restricted for use in individuals with a known hypersensitivity to any of its components.

Q: Are there any specific warnings for Keri regarding sun exposure?

Specific warnings regarding sun exposure or photosensitivity (increased sensitivity to light) are included in the official labeling if they are considered a known or potential risk for the product. These warnings are found in the official 'Warnings and Precautions' section.

Q: What is the role of Lactic Acid or Alpha Hydroxy Acids (AHAs) in some Keri formulations?

The official composition label must be checked to confirm if ingredients such as Lactic Acid or Alpha Hydroxy Acids (AHAs) are present as excipients. If found, their role is determined by their function in stabilizing or formulating the specific product.

Q: Is it true that some versions of Keri contain coal tar?

Coal tar is generally a topical agent, and the official composition list for the oral Nifuroxazide formulation (Keri) is the definitive source to confirm its ingredients. It is not typically listed as an ingredient in oral intestinal antiseptics.

Q: Does Keri contain any ingredients derived from animals?

The official product composition and excipients list specifies all components used. This information can be used to determine the presence of any animal-derived ingredients, such as gelatin found in some capsules.

How should Keri be stored and disposed of?

Storage and Protection Requirements

Storage of Keri (Nifuroxazide) must adhere to conditions that preserve the product's stability, as defined by regulatory labeling.

  • Temperature Control: Solid dosage forms (tablets/capsules) are generally required to be stored at room temperature, which is typically defined as Below 25 C or 30 C. All forms must be protected from freezing.
  • Packaging Integrity: The medication should be stored in the original package and protected from moisture/humidity. The container must be kept tightly closed.
  • Suspension Stability: The Oral Suspension form, once prepared, has a limited in-use stability period, often requiring refrigeration and discarding any unused portion after a short, labeled timeframe (e.g., 7 or 14 days).
  • Child Safety: A mandatory safety requirement is to Keep out of the sight and reach of children.

Official Disposal Instructions

Unused or expired Keri must be handled according to official pharmaceutical waste guidelines. The product should not be thrown into wastewater or general household trash. Patients are instructed to dispose of the unused product according to local regulations, typically by utilizing a community drug take-back program.

Attention! Always consult to a doctor or pharmacist before using pills or medicines.

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