Zabak

Overdose

No case of overdose has been reported.

Oral ingestion of the contents of a 5ml bottle would be equivalent to 1.25mg of ketotifen which is 60% of a recommended oral daily dose for a 3 year old child. Clinical results have shown no serious signs or symptoms after oral ingestion of up to 20mg of ketotifen.

Incompatibilities

Not applicable.

Pharmaceutical form

Eye drops, solution

Undesirable effects

Adverse reactions are ranked under heading of frequency, using the following convention: Very common (>1/10); common (>1/100 to <1/10); uncommon (>1/1,000 to <1/100); rare (>1/10,000 to <1/1,000); very rare (<1/10,000), not known (cannot be estimated from the available data).

Immune system disorders

Uncommon: Hypersensitivity

Nervous system disorders

Uncommon: Headache

Eye disorders

Common: Eye irritation, eye pain, punctate keratitis, punctate corneal epithelial erosion.

Uncommon: Vision blurred (during instillation), dry eye, eyelid disorder, conjunctivitis, photophobia, conjunctival haemorrhage.

Gastrointestinal disorders

Uncommon: Dry mouth

Skin and subcutaneous tissue disorders

Uncommon: Rash, eczema, urticarial

General disorders and administration site conditions

Uncommon: Somnolence

Adverse drug reactions from post-marketing experience (Frequency not known):

The following post marketing events have also been observed: hypersensitivity reactions including local allergic reaction (mostly contact dermatitis, eye swelling, eyelid pruritis and oedema), systemic allergic reactions including facial swelling/oedema (in some cases associated with contact dermatitis) and exacerbation of pre-existing allergic conditions such as asthma and eczema.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme. Website: www.yellowcard.mhra.gov.uk

Preclinical safety data

Preclinical data reveal no special hazard which is considered relevant in connection with use of Zaditen eye drops in humans based on conventional studies of safety pharmacology, repeated dose toxicity, genotoxicity, carcinogenic potential and toxicity to reproduction.

Therapeutic indications

Symptomatic treatment of seasonal allergic conjunctivitis.

Pharmacotherapeutic group

Ophthalmologicals, other antiallergics

Pharmacodynamic properties

Pharmacotherapeutic group: Ophthalmologicals, other antiallergics

ATC code: S01GX08

Ketotifen is a histamine H1-receptor antagonist. In vivo animal studies and in vitro studies suggest the additional activities of mast cell stabilisation and inhibition of infiltration, activation and degranulation of eosinophils.

Pharmacokinetic properties

In a pharmacokinetic study conducted in 18 healthy volunteers with Zaditen eye drops, plasma levels of ketotifen after repeated ocular administration for 14 days were in most cases below the limit of quantitation (20pg/ml).

After oral administration, ketotifen is eliminated biphasically with an initial half-life of 3 to 5 hours and a terminal half-life of 21 hours. About 1% of the substance is excreted unchanged in the urine within 48 hours and 60 to 70% as metabolites. The main metabolite is the practically inactive ketotifen-Nglucuronide.

Name of the medicinal product

Zabak

Qualitative and quantitative composition

Ketotifen Fumarate

Special warnings and precautions for use

The formulation of Zaditen eye drops contains benzalkonium chloride as a preservative, which may be deposited in soft contact lenses; therefore Zaditen eye drops should not be instilled while the patient is wearing these lenses. The lenses should be removed before application of the drops and not reinserted earlier than 15 minutes after use.

All eye drops preserved with benzalkonium chloride may possibly discolour soft contact lenses. Benzalkonium chloride may cause eye irritation.

Effects on ability to drive and use machines

Any patient who experiences blurred vision or somnolence should not drive or operate machines.

Dosage (Posology) and method of administration

Adults, elderly and children (age 3 and older): one drop of Zaditen into the conjunctival sac twice a day.

The contents and dispenser remain sterile until the original closure is broken.

To avoid contamination do not touch any surface with the dropper tip.

The safety and efficacy of Zaditen in children aged from birth to 3 years have not yet been established.

Special precautions for disposal and other handling

No special requirements.