Ketotifen is a cycloheptathiophene derivative with anti-allergic activity. Ketotifen selectively blocks histamine (H1) receptors and prevents the typical symptoms caused by histamine release. This agent also interferes with the release of inflammatory mediators from mast cells involved in hypersensitivity reactions, thereby decreasing chemotaxis and activation of eosinophils. Ketotifen is a cycloheptathiophene blocker of histamine H1 receptors and release of inflammatory mediators. It has been proposed for the treatment of asthma, rhinitis, skin allergies, and anaphylaxis.
Ketotifen is a first-generation noncompetitive H1-antihistamine and mast cell stabilizer. It is most commonly sold as a salt with a fumaric acid, ketotifen fumarate, and is available in two forms. In its ophthalmic form, it is used to treat allergic conjunctivitis. In its oral form, it is used to prevent asthma attacks or Anaphylaxis, as well as various mast cell, allergic-type disorders cycloheptathiophene blocker of histamine H1 receptors and release of inflammatory mediators. It has been proposed for the treatment of asthma, rhinitis, skin allergies, and anaphylaxis.
Mechanism of action of Ketotifen
Ketotifen is a relatively selective, non-competitive histamine antagonist (H1-receptor) and mast cell stabilizer. Ketotifen inhibits the release of mediators from mast cells involved in hypersensitivity reactions. Decreased chemotaxis and activation of eosinophils have also been demonstrated. Ketotifen also inhibits cAMP phosphodiesterase. Properties of ketotifen which may contribute to its antiallergic activity and its ability to affect the underlying pathology of asthma include inhibition of the development of airway hyperactivity associated with activation of platelets by PAF (Platelet Activating Factor), inhibition of PAF-induced accumulation of eosinophils and platelets in the airways, suppression of the priming of eosinophils by human recombinant cytokines and antagonism of bronchoconstriction due to leukotrienes. Ketotifen inhibits of the release of allergic mediators such as histamine, leukotrienes C4 and D4(SRS-A) and PAF.
Indications of Ketotifen
- Conjunctivitis, Allergic
- Asthma, Allergic
- Conjunctivitis, Seasonal Allergic
- Allergic rhinitis,
- Allergic conjunctivitis,
- Atopic dermatitis,
- Chronic urticaria,
- Cold-induced urticaria,
- Cholinergic urticaria,
- Exercise-induced urticaria,
- Systemic mast cell disease including mastocytosis,
- Allergic and nonallergic anaphylaxis,
- Angioedema
- Food allergy
- Indicated as an add-on or prophylactic oral medication in the chronic treatment of mild atopic asthmatic children. Also used as self-medication for the temporary relief of itching of the eye due to allergic conjunctivitis (ophthalmic).
Contra-Indications of Ketotifen
- No Disease Contraindications
Allergies
- Ketotifen
- Antihistamines
- Antihistamines – Piperidine
- Mast Cell Stabilizer
Dosage of Ketotifen
Allergic Conjunctivitis
- Instill 1 drop in the affected eye(s) 2 times a day
Allergic Conjunctivitis
- Age: 3 years and older
- Instill 1 drop in the affected eye(s) 2 times a day
Side Effects of Ketotifen
The most common
- abdominal pain
- drowsiness
- dry mouth
- headache
- increased appetite
- irritability
- nausea
- nervousness
- sleep disturbances (e.g., trouble sleeping)
- slight dizziness
- weight gain
Opthalmic
- redness, drainage, eyelid swelling, or other signs of infection;
- eye pain;
- vision changes; or
- severe itching of the eyes worse than before using the medication.
- mild burning, stinging, or eye irritation;
- dryness of the eyes; or
- increased sensitivity to light.
More common
- headache
- fever, flu symptoms;
- seizure (convulsions); or
- jaundice (yellowing of the skin or eyes).
- dry mouth, sore throat, cough;
- muscle pain;
- drowsiness, tired feeling;
- nausea,
- fever, flu symptoms;
- seizure (convulsions); or
- jaundice (yellowing of the skin or eyes).
Less common
- Dizziness
- dry mouth
- dysmenorrhea, such as difficult or painful menstruation
- dyspepsia, such as acid or sour stomach, belching, heartburn, indigestion, stomach discomfort, upset or pain,
- fatigue, such as unusual tiredness or weakness
- myalgia, such as joint pain, swollen joints, muscle aching or cramping, muscle pains or stiffness, difficulty in moving
- pharyngitis, such as, body aches or pain, congestion, cough, dryness or soreness of throat, fever, hoarseness, runny nose, tender swollen glands in neck, trouble in swallowing, voice changes.
- somnolence, such as, sleepiness or unusual drowsiness
- nausea
- liver damage or inflammation
- tightness in the chest or breathing tube
Drug Interactions
Tell your doctor of all nonprescription and prescription medication you may use, especially of: oral drugs used for diabetes. Also report drugs that may cause drowsiness such as sleeping pills, anti-anxiety drugs, psychiatric medicines, certain antihistamines (e.g., diphenhydramine), muscle relaxants, narcotic pain relievers (e.g., codeine), anti-seizure drugs. Certain cough-and-cold preparations may also make you drowsy. Consult your pharmacist. Do not start or stop any medicine without doctor or pharmacist approval.
- benzphetamine
- brompheniramine
- buprenorphine
- buprenorphine buccal
- butabarbital
- butalbital
- butorphanol
- caffeine
- carbinoxamine
- carisoprodol
- chloral hydrate
- chlordiazepoxide
- chlorpheniramine
- chlorpromazine
- chlorpropamide
- chlorzoxazone
- cinnarizine
- clemastine
- clomethiazole
Pregnancy and Lactation
FDA Pregnancy Category C
Pregnancy
Ketotifen should not be used by anyone who is pregnant or breastfeeding.
Lactation
Ketotifen should not be used by anyone who is pregnant or breastfeeding. Pregnancy
References
