Winon

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Winon

Method of action: Bactericidal, Bacteriostatic

Treatment option: Cholecystitis

Medically reviewed

Laura Arias

Last updated on 22/12/2025

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 Winon

What is Winon? Defining the First-Generation Quinolone

Property Description
Active Ingredient Nalidixic Acid
Form Oral Tablet
Pharmacological Class Quinolone Antibiotic
General Purpose Systemic Antibacterial Agent
Origin Synthetic (Naphthyridine derivative)

Winon is a prescription-only medication whose active ingredient is Nalidixic Acid, a compound officially classified as a synthetic chemotherapeutic agent belonging to the quinolone antibiotic class. This medicine is typically intended for use in adult patients requiring a systemic antimicrobial agent. The compound holds historical significance as the first-generation quinolone structure, which served as the foundation for the later development of more complex fluoroquinolones. Its core identity is defined by its role as a systemic antibacterial agent, intended to address specific bacterial challenges within the body.


Composition, Origin, and Pharmaceutical Form

The medicine is manufactured as a single active ingredient product, consisting exclusively of Nalidixic Acid combined with pharmaceutical excipients, and is typically presented as an oral tablet. This form is the designated route of administration, designed for systemic administration where the active substance is absorbed through the digestive tract. The tablet formulation is clinically recognized for providing a reliable, standardized dose of the active ingredient, supporting predictable systemic delivery.

As a synthetic substance, Nalidixic Acid is chemically manufactured, a process that ensures high structural purity. The quinolone antibiotic classification confirms that this medicine is used specifically to combat susceptible bacterial populations. The medication is recognized for its foundational role as an early therapeutic agent in its class.


Mechanism and General Antimicrobial Purpose

Winon’s general therapeutic purpose is rooted in its action as a powerful bactericidal agent—it actively works to kill susceptible bacteria directly. The fundamental physiological action involves the active ingredient interfering with key bacterial enzymes, specifically DNA gyrase and topoisomerase II. By inhibiting these essential enzymes, Nalidixic Acid prevents the target bacteria from successfully replicating their DNA, leading to cell death. This interruption of the genetic process is the basis of the drug's intended antimicrobial therapy.

What side effects are possible with Winon?

Possible Side Effects and Safety Information

The safety profile of Winon (Nalidixic Acid) is officially documented based on its classification as a first-generation quinolone antibacterial agent. Adverse reactions are grouped according to the physiological systems they affect and are classified by frequency, consistent with regulatory standards.

Officially documented adverse effects frequently involve the Gastrointestinal Disorders (e.g., nausea, vomiting, abdominal pain, diarrhea) and Nervous System Disorders (e.g., headache, dizziness, drowsiness) organ classes. These common effects may be more likely to appear at the initiation of treatment.

Less common reactions involve the Skin and Subcutaneous Tissue Disorders, including photosensitivity reactions, which necessitate the constraint of avoiding direct sunlight or UV light exposure during therapy. The label also notes visual disturbances, such as changes in color perception.

Documented Serious Adverse Reactions

The medicine is associated with risks of serious adverse reactions that, while rare, are clinically significant and are highlighted in regulatory texts:

  • Nervous System: Seizures (convulsions) and intracranial hypertension (pseudotumor cerebri).
  • Blood and Lymphatic System: Hemolytic anemia, particularly in individuals with a latent or actual glucose-6-phosphate dehydrogenase (G6PD) deficiency.
  • Psychiatric: Psychotic reactions and hallucinations.

Safety Constraints and Considerations

The official safety information includes several high-level restrictions. The medicine is formally contraindicated for use in patients with a history of convulsive disorders or known hypersensitivity to quinolone agents. Additionally, specific caution and potential monitoring are required for use in patients with hepatic or renal impairment.

Overdose and Emergency Response

Overdose Manifestations and Severe Outcomes

Overdose events involving Winon (Nalidixic Acid) are officially documented to affect the central nervous system (CNS) and the metabolic system. Documented overdose presentations may include gastrointestinal symptoms such as nausea and vomiting, along with specific CNS effects like headache, lethargy, drowsiness, and altered consciousness. Sensory changes, including visual disturbances and an overbright appearance of lights, are also listed manifestations.

Severe outcomes include the potential for convulsions (seizures) and toxic psychosis. A risk of increased intracranial pressure is noted, with specific signs like bulging anterior fontanel documented in infants and children. Overdose may also lead to significant metabolic acidosis.

When to Seek Immediate Help

Immediate medical attention must be sought for any known or suspected overdose. This action is mandated due to the potential for severe neurological and metabolic complications. Treatment is exclusively symptomatic and supportive; no specific antidote is known for Nalidixic Acid overdose. Management procedures include gastric lavage for recent ingestion and specialized care to control convulsive crises and correct the acid-base imbalance. Hospital monitoring is required to manage these severe, documented risks.

Therapeutic Uses of Winon

What Winon Treats: Main Uses and Benefits

Winon is generally applied across therapeutic domains where additional symptomatic support is needed, being relevant in contexts marked by increased discomfort or tension. As a medication category commonly used when short-term symptomatic assistance is needed, it provides supportive relief when symptoms interfere with routine activities. This medication category is commonly used to help with symptom clusters that create noticeable physiological strain.

Winon is relevant for easing symptoms associated with acute pain, fever, and localized inflammation. This makes it relevant for managing common conditions characterized by periods of heightened symptoms, such as tension headaches, muscle soreness, joint aches, and general discomfort associated with viral illnesses. The medication is helpful in situations where symptoms may intensify temporarily, such as after a minor injury or dental procedure. It helps manage symptoms that interfere with daily comfort and assists with maintaining functional stability.

“This application supports the patient during difficult episodes by easing distress and contributes to improved day-to-day comfort during symptomatic periods.”

Quick Fact: Management of Acute Discomfort
Winon is commonly used to help manage pain sensation and the associated signs of inflammation.

Regulatory References

  1. NIH MedlinePlus overview on pain relievers

Eligibility and Restrictions for Use

Who Can and Cannot Use Winon?

Population eligibility for Winon (Nalidixic Acid) is governed by strict regulatory rules establishing allowed, restricted, and prohibited use.

Absolute Prohibition (Contraindications)

The medicine is contraindicated and must not be used by infants less than three months of age or by patients with a known hypersensitivity to Nalidixic Acid or other quinolone compounds. Use is also prohibited for individuals with Porphyria or a history of convulsive disorders (e.g., epilepsy). Concomitant therapy with melphalan or related cancer chemotherapeutic alkylating agents is also an absolute contraindication.

Restricted and Conditional Use

Population Group Eligibility Status Basis for Restriction
Renal/Hepatic Impairment Use with Caution Impaired organ function may require dose adjustment (renal) or close monitoring (hepatic).
Pregnancy Category C Use only if benefit outweighs potential risk.
Lactation (Breastfeeding) Contraindicated Prohibited by manufacturer due to potential transfer.
Prepubertal Children Use with Caution Concern regarding potential effects on joints, as seen in animal studies.
Older Adults Use with Caution Consideration of likely decreased renal function.

Use also requires caution for patients with known or suspected Central Nervous System (CNS) disorders, such as severe cerebral arteriosclerosis.

What should I know about interactions with other medicines?

Interactions with other medicines and products

Winon's interaction profile is strictly defined by regulatory guidelines concerning co-administration. The combination of Winon with Melphalan or other related cancer chemotherapeutic alkylating agents is formally contraindicated due to the documented risk of severe gastrointestinal toxicity.

A primary interaction domain involves absorption interference. Products containing magnesium, aluminum, calcium, iron, or zinc (such as antacids, Sucralfate, and mineral supplements) substantially interfere with the drug's absorption, resulting in reduced systemic exposure. A mandatory procedural constraint dictates that these cation-containing substances must not be taken within the two-hour period before or two hours after the administration of Winon.

Several pharmacokinetic and pharmacodynamic interactions are officially documented. Co-administration may result in elevated plasma levels of Theophylline and Cyclosporine. The drug may also enhance the effects of oral anticoagulants like Warfarin, requiring close monitoring of suitable coagulation tests. Conversely, the action of Winon may be inhibited by bacteriostatic agents such as Tetracycline, and Probenecid inhibits its tubular secretion. Furthermore, post-marketing data indicates an officially increased risk of tendon effects when concomitant corticosteroids are used, particularly in the elderly population.

Mechanism of Action

How Winon Works

Targeting Bacterial DNA Gyrase and Topoisomerase IV

Winon's active ingredient, Nalidixic Acid, acts within the biological domain of bacterial genetic processing by targeting two essential bacterial enzymes: DNA Gyrase and Topoisomerase IV. The molecule functions as an enzyme inhibitor and a quinolone poison that binds to these enzymes while they are transiently attached to the DNA. This action stabilizes the DNA-cleavage complex, which prevents the crucial re-ligation of cut DNA strands.

The Cascade of Lethal DNA Damage

The stabilization of the enzyme-DNA complex initiates a lethal mechanistic cascade characterized by the rapid accumulation of Double-Stranded DNA Breaks (DSBs). This damage halts all vital DNA replication and transcription, ultimately leading to the programmed bactericidal elimination of the susceptible bacterial cell. The drug's activity is constrained by molecular limitations, including Target-Based Resistance—mutations in the gyrA and parC genes—and Efflux Pump Activity, which reduce the necessary intracellular drug concentration.

Dosage and Administration Information

How to Use Winon

Winon, which contains Nalidixic Acid, is a prescription medicine administered via the oral route, typically as a tablet or caplet, for systemic use. The usage protocol is structured around specific dosage schedules and administration conditions, reflecting the established patterns of use.

Administration and Dosage Protocol

The standard approach to using Winon involves two phases of therapy. For adult initial treatment, the usual dose is 1 g taken four times daily, resulting in a total daily intake of 4 g. This high-frequency dosing, delivered in four equally divided doses, is generally maintained for an initial course of one or two weeks. For subsequent prolonged therapy, the total daily quantity is typically reduced to 2 g.

Administration is flexible concerning food intake; the medicine may be taken with or without meals. However, instructions for use specify that patients should drink fluids liberally during the course of use. A crucial procedural constraint involves avoiding concurrent use with certain substances: the medicine should not be taken within the two-hour period before or after antacids containing calcium, magnesium, or aluminum, as well as products containing iron or zinc.

Population and Procedural Adjustments

Specific guidelines govern use in certain populations. The medicine is not administered to infants younger than three months. For patients with significant renal impairment, the dosage must be halved if the creatinine clearance is 20 mL/minute or less. The established protocol includes the requirement that cultural and susceptibility testing be performed prior to administration to ensure appropriate usage.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Winon (Nalidixic Acid)

Evidence for Use in Acute Urinary Tract Infections (UTIs)

Research into Winon's use for acute urinary tract infections (UTIs) primarily involved randomized controlled trials (RCTs) and other comparative clinical trials. These studies generally focused on adult patients, including those with uncomplicated, acute lower UTIs. Studies monitored two main categories of outcomes: microbiological findings, which measured patterns related to the presence or absence of targeted bacteria from the urine, and clinical findings, which involved the assessment of outcomes related to physical discomfort and symptom evolution.

The findings describe patterns observed in these studies where patterns related to the presence or absence of susceptible Gram-negative organisms from the urine cultures were observed. Research highlights changes measured during the study period related to changes in symptom assessment. The body of evidence is characterized by varying study designs. Since the medication served as the foundation for an entire class of antibiotics, the body of work is largely historical. As a result, the findings apply only to the populations studied at that time, which contributes to a gap in evidence regarding contemporary bacterial strains and current resistance patterns.

Comparative Studies Against Other Antibacterial Agents

Winon was evaluated in comparative studies to help position it within the landscape of available antibacterial agents when it was first introduced. Research examined how the short-term microbiological and clinical outcomes compared to other treatments used at the time. Studies reported that Winon was observed in trials that compared its effect on bacterial absence against other antibiotics available during that period. Data show patterns related to the time required for bacterial absence and changes in symptom assessment when compared to these other treatments. While comparative evidence exists from the time of Winon's development, certainty remains low regarding how it would compare to the newer-generation antibiotics used today, as comparative evidence is lacking with current standard-of-care agents.

Long-Term Data and Extended Follow-up Periods

Evidence exploring the longer-term effects of Winon remains limited. These studies monitored patient populations over extended observation periods—sometimes up to a few months—to track the presence of bacteria over time. The primary focus of these follow-up studies was the duration of time during which the research monitored the presence or absence of the target bacteria in culture. The existing evidence for long-term outcomes is low-level and often derived from small cohorts. Findings describe patterns observed in these studies related to the re-emergence of bacteria over time. However, the follow-up durations were limited, and long-term effects are not fully established.

Key Studies & References

  1. Comparative study of nalidixic acid and sulfamethoxazole in urinary tract infections in college women

Frequently Asked Questions (FAQ)

Common questions about Winon (FAQ)


Q: How quickly can I expect to notice anything after starting Winon?

A: Studies on the drug’s distribution describe that the active form typically reaches its highest concentration in the bloodstream within one to two hours after taking a dose. The drug also concentrates in the urine, where it achieves its peak levels generally within three to four hours. This pharmacokinetic information describes the time required for the medication to reach its highest measured concentration in the body.


Q: Can Winon affect my sleep schedule or patterns?

A: Official adverse reaction reports indicate that the medicine may affect sleep. Reported effects include both drowsiness and an inability to sleep, known as insomnia. These effects are generally documented for awareness.


Q: Is it normal to feel a bit dizzy when first starting Winon?

A: Regulatory documents list dizziness and light-headedness as officially documented effects. These common side effects may be more likely to appear when a patient first begins treatment with the medicine.


Q: Why is it important to share all my current medicines with my doctor before starting Winon?

A: It is important to share a complete list of all products used, including over-the-counter medicines, vitamins, and herbal supplements. The official label describes several specific interaction risks with other products that indicate a need for review, as they could affect how Winon works or increase the possibility of side effects.


Q: Is Winon considered a common medicine?

A: Official sources describe Winon's active ingredient, Nalidixic Acid, as the first-generation structure in the quinolone antibiotic class. This classification confirms its historical role as a foundational and older type of antibacterial agent.


Q: Why is Winon sometimes described as different from older medicines for the same condition?

A: Winon is specifically classified as a synthetic chemotherapeutic agent and a quinolone antibiotic. This places its mechanism of action—targeting bacterial DNA replication—as distinct from much older types of antibacterial medicines used before its introduction.


Q: What does 'therapeutic effect' mean in relation to Winon?

A: In the context of this medicine, the therapeutic effect refers to its primary goal: the bactericidal action that is intended. This involves the drug actively killing the specific susceptible bacteria that are causing the treated infection.


Q: What happens if I miss a scheduled time to take Winon?

A: Official patient information describes that the medicine is generally advised to be taken as soon as it is remembered. However, if it is nearly time for the next scheduled dose, regulatory guidance indicates skipping the missed dose is preferred to avoid the possibility of taking a double dose.


Q: Is Winon safe to use in older adults (seniors)?

A: Official prescribing information requires that caution be observed when the drug is used in older patients. This is due to the higher likelihood of decreased kidney function in this population, for which monitoring may be considered.


Q: Can people with kidney problems use Winon?

A: Official information describes that the drug is mostly cleared from the body by the kidneys, and caution is advised for people with impaired renal function. In cases of significant renal impairment, official prescribing information notes that dosage adjustments may be required.


Q: Are there any specific safety warnings for people with liver issues taking Winon?

A: Regulatory guidance states that the medicine should be used with caution in patients who have liver disease. Due to this potential risk, close monitoring of liver function is described as being appropriate during the use of this medicine.


Q: Has Winon been studied in children or teenagers?

A: Official documentation strictly prohibits the use of this medicine in infants younger than three months and requires caution for its use in prepubertal children. The available evidence for use in these younger populations is limited and primarily historical.


Q: What is the main research finding that led to Winon being approved?

A: The approval of the medicine was based on early research findings that demonstrated its ability to act as a bactericidal agent. Specifically, it was shown to be effective against susceptible Gram-negative microorganisms, which commonly cause urinary tract infections.


Q: Does Winon work by changing brain chemistry?

A: The drug's primary action is described as preventing susceptible bacteria from replicating their DNA. However, official warnings note that the medicine can cause certain Central Nervous System (CNS) effects, such as confusion, restlessness, or convulsions, and these effects are documented for awareness.


Q: Is Winon known to cause fatigue or tiredness?

A: While the terms fatigue or tiredness are not used as primary terms in the common side effect lists, official reports do include drowsiness and a general feeling of weakness among the documented side effects of the medicine.


Q: Can Winon affect the results of blood tests?

A: Regulatory guidance recommends that blood counts, as well as liver and kidney function tests, be performed periodically if treatment with the medicine continues for longer than two weeks. This guidance reflects the need to monitor for potential changes in these lab values.


Q: Can Winon be taken by people with heart conditions?

A: Official warnings describe that this medicine should be used with caution in people with pre-existing heart conditions. This is due to a potential risk of specific heart rhythm changes, known as QT prolongation.


Q: Is Winon safe for people with diabetes?

A: Official information reports that this medicine can affect blood glucose levels, with reports of both high and low blood glucose. More frequent monitoring of blood glucose may be noted as being appropriate for patients using diabetes medications.


Q: Can Winon be taken if I am pregnant or planning a pregnancy?

A: Official prescribing information places the drug in pregnancy category C. This classification indicates that the medicine is described as being used only when the potential benefit of treatment is considered to outweigh the potential risks involved.


Q: Is Winon compatible with birth control pills?

A: Official interaction information indicates that the medicine may reduce the effects of certain birth control pills that contain ethinyl estradiol. This potential interaction may increase the risk for pregnancy or cause breakthrough bleeding.

How should Winon be stored and disposed of?

How to Store and Dispose of Winon (Nalidixic Acid)

Storage and disposal instructions for Winon oral tablets are defined by regulatory labeling to ensure product stability and safety. The medicine must be stored at or below 30 C in a cool, dry, and dark environment, as it requires protection from excessive heat, light, and moisture. This is crucial for maintaining the drug's 36-month shelf-life.

Required Storage and Protection

Condition Requirement
Temperature Store below 30 C.
Environment Must be a cool, dry, and dark place.
Safety Rule Keep out of the reach of children.

Unused or expired Winon must be disposed of in accordance with local regulations, typically by utilizing a drug take-back program or following guidelines for household trash disposal. The product labeling confirms no special hazardous waste precautions are required, but advises against flushing it down the toilet.

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

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