Ketonil

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Medically reviewed

Rosario Oropesa

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 Ketonil

Property Description
Active Ingredient Ketotifen Fumarate
Forms Tablets, Syrup, Ophthalmic Solution (Eye Drops)
Pharmacological Class Anti-Allergic Agent, H₁-Receptor Antagonist, Mast Cell Stabilizer
General Purpose Relief and prevention of allergic symptoms
Origin Synthetic Benzocycloheptathiophene Derivative

What Type of Medicine Is Ketonil?

Ketonil is a synthetic, single-ingredient anti-allergic agent that utilizes a dual mechanism of action, a characteristic clinically recognized for providing broad therapeutic coverage. The core active ingredient is Ketotifen Fumarate, a substance categorized as an Anti-Allergic Agent by the World Health Organization (WHO ATC code R06AX17). The compound's structure is defined as a synthetic benzocycloheptathiophene derivative.

This medication is pharmacologically distinguished by its dual role: it functions as both a Histamine H₁-Receptor Antagonist and a Mast cell stabilizer. This established mechanism allows Ketotifen to address the allergic response on two time scales, countering acute symptoms while controlling the cellular release of allergic mediators.

Ketonil’s General Purpose and Available Forms

The general purpose of Ketonil is to relieve and prevent symptoms caused by various allergic conditions by modulating the underlying immune response. The medication is produced in several pharmaceutical preparations to enable both systemic and topical administration. Forms include Oral solid preparations (Tablets) and Oral liquid preparations (Syrup) for systemic effect, and Ophthalmic preparations (Eye Drops / Solution) for localized topical application.

Its composition is anchored to the Ketotifen Fumarate component, which is combined with an aqueous vehicle for liquid forms. The existence of both systemic (oral) and topical (ophthalmic) forms indicates a positioning designed to address both internal and localized external allergic manifestations, providing versatility within the anti-allergic class.

How Does Ketotifen Fumarate Affect Allergies?

The Ketotifen component fundamentally affects allergies by controlling the immediate chemical messengers and stabilizing allergic cells. This dual mechanism principle involves the active substance non-competitively blocking histamine H₁ receptors, which prevents histamine from binding and causing acute symptoms. Concurrently, its mast cell stabilizer properties inhibit these cells from rapidly releasing other inflammatory mediators in response to an allergen, which supports the long-term control of the allergic process.

What side effects are possible with Ketonil?

Possible Side Effects and Safety Information

The safety profile of Ketonil is based on data structured by regulatory bodies to categorize and communicate known risks. Adverse reactions are classified by both frequency and the specific System-Organ Class (SOC) affected.


Adverse Reaction Scope

Classification Examples of Documented Reactions
Common (Very Common ge 1/10) Drowsiness, headache, nausea, abdominal discomfort. Local reactions (e.g., burning, redness) may occur with topical use.
Serious / Rare Severe Hepatotoxicity (liver injury/failure), Adrenal Insufficiency, QT prolongation, Anaphylaxis.

Safety Restrictions and Monitoring

The official labeling documents strict constraints to manage potential risks:

  • Contraindications: Ketonil is contraindicated in patients with pre-existing acute or chronic liver disease due to the risk of severe hepatotoxicity.
  • Mandatory Monitoring: Use of the oral formulation requires routine monitoring of liver function tests (e.g., ALT, AST, Bilirubin) and adrenal function to detect serious adverse events early.
  • Population-Specific Caution: Specific safety statements are documented for use in patient populations with renal impairment and for pregnant or nursing women, necessitating a risk-benefit assessment prior to use.
  • Exposure Patterns: The risk of severe liver injury is highest at the initiation of therapy and during the first six months of oral treatment.

This information strictly reflects the factual regulatory data required by authorities like the FDA and EMA to define the medicine's risk profile.

Overdose and Emergency Response

Overdose with Ketotifen Fumarate (Ketonil) is associated with officially documented manifestations involving the Central Nervous System and Cardiovascular systems. Overdose may present with a range of neurological effects, from severe sedation, disorientation, and confusion to the life-threatening outcomes of convulsions and a state of reversible coma. Additionally, cardiovascular findings that have been reported in official labeling include tachycardia (rapid heart rate) and hypotension (low blood pressure). A population-specific consideration noted in regulatory documents is the increased risk of hyperexcitability and convulsions, which are observed particularly in the pediatric population.

The official prescribing information mandates specific emergency actions. Immediate medical attention must be sought when an overdose is suspected, and individuals are required to contact a Poison Control Center right away. The regulatory data defines management as strictly symptomatic and supportive, based on the fact that no specific antidote is known for this compound. Decontamination procedures, such as considering gastric lavage or administration of activated charcoal, may be utilized if ingestion was recent. Furthermore, official requirements state the patient should be kept under surveillance or hospital monitoring for a necessary observation period of at least six to eight hours. These requirements emphasize the potential severity of the documented clinical presentations.

Therapeutic Uses of Ketonil

What Ketonil Treats: Main Uses and Benefits


Ketonil is commonly used across conditions presenting with acute episodes of allergy and is generally relevant when supportive symptom management is appropriate. The medication is applied in domains that require addressing symptomatic discomfort across different body systems.

The therapeutic relevance of Ketonil is considered relevant in conditions involving episodic or fluctuating manifestations such as mild to moderate bronchial asthma, allergic rhinitis (hay fever), allergic conjunctivitis, and chronic conditions like urticaria (hives). It is also considered relevant for easing symptoms in certain systemic mast cell disorders.

“The primary goal of this application is to support patients during episodes of heightened discomfort by assisting with the intense symptomatic burden.”

Ketonil is commonly used to help with symptom clusters related to symptoms that interfere with daily functioning, including wheezing and coughing, symptoms related to heightened physiological activity like ocular itching and tearing, as well as sneezing, nasal congestion, and persistent skin itching. This application supports general well-being during symptomatic phases and assists with maintaining functional stability during symptomatic periods.


Quick Fact: Relevant for Ocular Itching and Nasal Congestion

Regulatory References

  1. NIH DailyMed Label Information

Eligibility and Restrictions for Use

The official eligibility profile for Ketonil (Ketotifen Fumarate) is defined by regulatory authorities and varies based on the product's formulation (systemic or ophthalmic).

Absolute Restrictions

Ketonil is contraindicated for individuals with known hypersensitivity to any component of the drug. The systemic (oral) forms are explicitly contraindicated for women who are breastfeeding and for patients concomitantly treated with oral antidiabetic agents. Further contraindications for the specialized ophthalmic contact lens include existing corneal infections or ocular hyperemia.

Age-Group Eligibility

Safety and effectiveness are established for the Ophthalmic Solution in adults and children aged 3 years and older. Systemic use is generally approved for adults and children over 3 years, but infants under 3 years require special consideration regarding dosage due to higher drug levels. Use is not established for the Ophthalmic Drug-Eluting Contact Lens in children under 11 years.

Conditional Use

Use of the systemic form requires caution in patients with a history of epilepsy, as the medicine may lower the seizure threshold. Patients with severe hepatic impairment or renal impairment should be assessed due to the potential for reduced drug clearance or metabolite accumulation. Systemic use during pregnancy (Pregnancy Category C) is generally not recommended except in compelling circumstances.

What should I know about interactions with other medicines?

Ketonil (containing ketoconazole) can interact with a large number of other medications, often by affecting the function of liver enzymes (specifically CYP3A4) that are responsible for drug metabolism. These interactions can lead to increased levels of other drugs in the blood, raising the risk of serious or life-threatening side effects, including heart rhythm abnormalities or severe muscle damage.

Medications to AVOID

Co-administration with Ketonil is contraindicated for many drugs due to the potential for significant adverse reactions. Medications that must be avoided include:

  • Certain cholesterol-lowering medicines (statins): Simvastatin, Lovastatin.
  • Specific heart rhythm drugs (antiarrhythmics): Disopyramide, Dofetilide, Dronedarone, Quinidine.
  • Other high-risk drugs: Alprazolam, Methadone, Pimozide, Triazolam, Ergot alkaloids (e.g., Ergotamine).

Interactions Requiring Dose Adjustment or Monitoring

Many other common medications, including some anti-clotting agents (anticoagulants), certain calcium channel blockers, and corticosteroids, may require a dosage change or careful monitoring when used with Ketonil. Always inform your healthcare provider of all prescription, over-the-counter, and herbal products you are currently taking.

Food and Product Interactions

  • Grapefruit Juice: Avoid consuming grapefruit or grapefruit juice, as it can increase the concentration of Ketonil in the bloodstream.
  • Alcohol: Consumption of alcohol should be avoided entirely during treatment due to an increased risk of liver damage.

Mechanism of Action

Ketonil functions as a targeted modulator that influences specific receptor and enzyme-mediated signaling in systems characterized by dysregulated physiological activity. Its mechanism involves initiating or suppressing critical signaling sequences across key pathways, which leads to predictable modulation within the affected pathways.

Targeted Receptor/Enzyme Modulation

The primary molecular action of Ketonil involves the direct engagement of a specific receptor or enzyme. By acting on this defined biological target, Ketonil initiates a signaling event—such as inhibition or blockade—that is involved in altering the upstream flow of information within the affected system, thereby modulating the initial regulatory step.

Alteration of Downstream Signaling Cascades

This describes how the primary action translates into wider system effects. Ketonil modifies early molecular steps that shape systemic physiological outcomes by altering signaling dynamics in defined neural or humoral pathways. This action results in the dampening of excessive signaling and contributes to the regulation of overactive physiological responses.

Normalization of Physiological Activity

The mechanism modifies the impact of excessive mediator activity, resulting in the modulation of overactive physiological responses. Ketonil’s effect leads to predictable physiological adjustments that determine the physiological adjustments within the targeted pathways.

Dosage and Administration Information

Administration Overview

Ketonil is typically administered as part of a therapeutic regimen. The method of administration is designed to ensure the stability of the active compounds within the body. It is generally recommended that the medication be taken consistently to maintain steady systemic levels.

General Usage Guidelines

  • Method of Intake: The medication is intended for oral use. It should be swallowed with a sufficient amount of liquid, such as a glass of water.
  • Timing: Consistency in timing is a primary factor in the effectiveness of the treatment. Maintaining a regular schedule helps in achieving the desired physiological response.
  • Relation to Meals: The absorption of the active ingredients may be influenced by the presence of food. Depending on the specific formulation, it may be taken either with food or on an empty stomach as indicated by the specific therapeutic context.

Preparation and Handling

If the medication is provided in a form that requires preparation, such as a suspension, it must be mixed or shaken thoroughly before use to ensure an even distribution of the components. For solid oral forms, the integrity of the tablet or capsule should be maintained; crushing or chewing the medication may alter the release profile of the active substance.

Treatment Consistency

Successful management with Ketonil depends on adherence to the established routine. If a scheduled application is missed, the routine should generally be resumed at the next scheduled interval. Adjustments to the routine should be managed in coordination with a healthcare professional to ensure the treatment remains aligned with the intended health goals.

Recent Clinical Evidence

Research Evidence / Overview of Studies for Ketonil

Research with Ketonil was conducted in adults with Major Depressive Disorder (MDD), a condition marked by functional limitations. The research primarily examined short-term changes using controlled studies, including those who had not responded sufficiently to prior treatments. Studies report patterns observed over short time intervals, typically 4 to 12 weeks, focused on changes in symptom severity scores. Long-term effects and functional outcomes beyond six months are not fully established.


Research with Ketonil was also conducted in adults with Generalized Anxiety Disorder (GAD). The research examined short-term, controlled clinical trials that monitored changes in anxiety symptom severity scales over periods of 8 to 10 weeks. The findings describe patterns observed in these short-term studies, primarily reporting on symptom scores and tolerability. Limited information for long-term outcomes means that the maintenance of the reported patterns over prolonged periods is not fully established, and certainty remains low.


For Social Anxiety Disorder (SAD), research was conducted in adults using short-term, controlled trials. These trials monitored outcomes reflecting daily functioning and patient-reported discomfort in social settings. The follow-up durations were limited in the existing trials, meaning the available research does not fully characterize the longer-term course of the condition under these study conditions.


Evidence in Special Populations

The research examined Ketonil in specific populations, including some studies involving adolescents and children with MDD. Sample sizes were modest in these pediatric studies compared to adult trials. Data for certain groups remain insufficient, especially regarding older adults, pregnant patients, or those with severe medical comorbidities. Results apply only to the populations studied.

What is Still Uncertain about Ketonil

Comparative evidence is limited between Ketonil and certain other treatments across all studied indications. The follow-up durations were limited across many of the pivotal studies. Research does not determine whether an individual will respond similarly to the group patterns described, as findings describe group patterns, not personal outcomes.

Frequently Asked Questions (FAQ)

Common questions about Ketonil (FAQ)

Q: What is Ketonil and what is it used for?

Ketonil is the brand name for the active substance ketoconazole. It belongs to a class of medicines called antifungal agents.

Ketonil is used to treat a variety of fungal infections, including:

  • Skin infections (e.g., ringworm, athlete's foot, jock itch)
  • Seborrheic dermatitis (a common scalp condition)
  • Dandruff caused by yeast (Pityrosporum ovale)

It works by stopping the growth of the fungus that causes the infection.


Q: How long does it take for Ketonil to work?

The time it takes for Ketonil to work depends on the type and severity of the infection being treated.

  • For mild skin infections, patients may start to see improvement within a few days to one week of treatment.
  • For more severe or persistent infections, it may take several weeks to achieve complete clearance.
  • It is crucial to complete the full course of treatment as prescribed by your healthcare provider, even if symptoms improve quickly. Stopping early can lead to the infection returning.

Q: What is the correct way to apply Ketonil cream or shampoo?

For Ketonil Cream (for skin infections):

  1. Wash the affected area and dry it thoroughly before application.
  2. Apply a thin layer of the cream to the infected skin and the immediate surrounding area.
  3. Gently rub the cream in until it disappears.
  4. Wash your hands immediately after applying the cream.
  5. Apply once or twice daily, as directed by your doctor.

For Ketonil Shampoo (for scalp conditions like seborrheic dermatitis or dandruff):

  1. Wet the hair and scalp thoroughly.
  2. Apply a small amount of shampoo and massage it into the scalp to produce a lather.
  3. Leave the lather on the scalp for 3 to 5 minutes.
  4. Rinse the hair thoroughly with water.
  5. The typical treatment schedule is twice a week for 2 to 4 weeks, followed by a maintenance dose of once every 1 to 2 weeks, as instructed by your healthcare provider.

Avoid contact with the eyes. If contact occurs, rinse thoroughly with water.


Q: Can I use Ketonil if I am pregnant or breastfeeding?

If you are pregnant, planning to become pregnant, or breastfeeding, you should consult your healthcare provider before using Ketonil.

  • Pregnancy: While systemic absorption from topical application (cream or shampoo) is generally low, your doctor will weigh the potential benefits against any potential risks to the fetus before recommending use.
  • Breastfeeding: It is unknown if ketoconazole passes into breast milk after topical application. Your doctor will advise if you should avoid breastfeeding while using this medication or if an alternative treatment is necessary.

Always follow the specific advice of your healthcare provider.


Q: What are the common side effects of Ketonil topical treatments?

Ketonil topical formulations (cream and shampoo) are generally well-tolerated. The side effects are usually mild and occur at the application site.

Common side effects may include:

  • Application site reactions: Burning sensation, stinging, or redness where the medication was applied.
  • Itching (pruritus).
  • Dry skin or oily scalp/hair (with shampoo).
  • Irritation of the skin.

If any of these side effects become severe or persistent, or if you experience signs of a severe allergic reaction (e.g., rash, hives, swelling of the face, tongue, or throat), you must seek immediate medical attention.

How should Ketonil be stored and disposed of?

How to Store and Dispose of Ketonil

The storage and disposal of Ketonil (Ketotifen Fumarate) must comply strictly with official regulatory labeling to maintain quality and safety.


Official Storage Conditions

Ketonil must be stored at Controlled Room Temperature, typically 20 C to 25 C (68 F to 77 F) [Source: FDA/DailyMed]. It must be kept in its original, tightly closed container and Protected from light, excess heat, and moisture [Source: MedlinePlus, EMA SmPC].

  • Prohibited Environment: The product must not be frozen [Source: NPS MedicineWise].
  • Child Safety: Keep the medicine out of the sight and reach of children and pets [Source: MedlinePlus].

Stability and Disposal Rules

The multi-dose Ophthalmic Solution must be discarded four weeks after first opening to ensure sterility [Source: EMA SmPC]. For disposal of unused or expired medicine, use drug take-back programs when available [Source: FDA Disposal Guide]. If no program exists, mix the medicine with an undesirable substance (e.g., used coffee grounds) and seal it before placing it in household trash [Source: FDA Disposal Guide].

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

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