Drugs List

Therapeutic Indications

Uses

Symptomatic treatment of seasonal allergic conjunctivitis.

Administration

For ocular administration.

Contraindications

Children under 12 years.

Precautions and Warnings

Epinastine eye drops contain benzalkonium chloride as a preservative, which may be deposited in soft contact lenses and may possibly discolour the lenses. Therefore, epinastine eye drops should not be instilled while the patient is wearing soft contact lenses. The lenses should be removed before application of the drops and not reinserted earlier than 15 minutes after use.

Benzalkonium chloride has been rarely reported to cause punctate keratopathy and/or toxic ulcerative keratopathy.

Epinastine is only licensed to be used for a maximum of 8 weeks.

Application may cause transient blurring of vision; patients should avoid driving or operating machines until vision is clear.

Pregnancy - see 'Pregnancy' section.

Breastfeeding - see 'Lactation' section.

Pregnancy and Lactation

Pregnancy

At the time of writing, there are a limited number (11) of exposed pregnancies, none of which indicate any adverse effects on the health of the foetus/neonate.

It is not known if epinastine crosses the placenta, though the molecular weight, low metabolism, moderate plasma protein binding and prolonged elimination half life suggest that this is likely. However, the low systemic bioavailability probably prevents clinically significant amounts from reaching the embryo/foetus. Briggs indicates that a lack of data prevents a complete assessment.

Animal data suggest low risk, and do not indicate any harmful effects with respect to pregnancy, embryonic/foetal development, parturition or postnatal development. At doses several thousand times higher than the maximum recommended ocular human dose, reproductive studies in rats and rabbits have found maternal toxicity, reduced pup body weight gain and resorption and abortion.

The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14-17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( www.toxbase.org ) or if this is unavailable at the backup site ( www.toxbasebackup.org ).

Lactation

It is not known if epinastine is excreted in human breast milk, but it is excreted in rats' milk. Other antihistamines obtaining therapeutic systemic concentrations are classified as compatible with breastfeeding, and Briggs indicates that epinastine be classed similarly.

The molecular weight, low metabolism, moderate plasma protein binding and prolonged elimination half life of epinastine suggest that excretion into human milk is likely, but LactMed concludes that, due to limited absorption from the eye, epinastine would not be expected to cause any adverse effects in breastfed infants.

LactMed also notes a study in which irritability and colicky symptoms were reported in 10% of infants exposed to various antihistamines (route taken unspecified), and drowsiness in 1.6%, none of which were of sufficient severity to require medical attention.

Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
Specialist advice is available from the UK Drugs in Lactation Advisory Service at https://www.midlandsmedicines.nhs.uk/content.asp?section=6&subsection=17&pageIdx=1

Drug excreted in breast milk? - Unknown, but considered likely.

Drug substance licensed in infants? - No.

Other information - Use with caution due to lack of experience, but other antihistamines are considered compatible, and epinastine has low systemic bioavailability.

Side Effects

Blepharoptosis
Conjunctival oedema
Conjunctival hyperaemia
Dry eyes
Photophobia
Visual disturbances
Headache
Asthma
Nasal irritation
Rhinitis
Dry mouth
Taste disturbances
Ocular pruritus
Blurred vision (transient)
Ocular burning
Ocular irritation
Ocular hyperaemia
Ocular discharge
Increased lacrimation
Ocular pain
Dysgeusia

Presentation

Eye drops containing epinastine hydrochloride 0.5mg/ml (equivalent to 0.436mg epinastine).

Drugs List

Therapeutic Indications

Uses

Symptomatic treatment of seasonal allergic conjunctivitis.

Dosage

Wash hands prior to use.

Avoid contact of the container with the eye or other surfaces as contamination leading to ophthalmic infection may occur.

To reduce systemic absorption compress the lacrimal sac during administration and for one minute afterwards.

Leave an interval of at least 10 minutes before instilling another ophthalmic medication.

Soft contact lenses should be removed before instillation of the eye drops and may be reinserted after 15 minutes.

Discard 4 weeks after first opening.

Adults

Elderly

Children

Patients with Renal Impairment

Patients with Hepatic Impairment

Additional Dosage Information

Administration

For ocular administration.

Contraindications

Children under 12 years.

Precautions and Warnings

Epinastine eye drops contain benzalkonium chloride as a preservative, which may be deposited in soft contact lenses and may possibly discolour the lenses. Therefore, epinastine eye drops should not be instilled while the patient is wearing soft contact lenses. The lenses should be removed before application of the drops and not reinserted earlier than 15 minutes after use.

Benzalkonium chloride has been rarely reported to cause punctate keratopathy and/or toxic ulcerative keratopathy.

Epinastine is only licensed to be used for a maximum of 8 weeks.

Application may cause transient blurring of vision; patients should avoid driving or operating machines until vision is clear.

Pregnancy - see 'Pregnancy' section.

Breastfeeding - see 'Lactation' section.

Pregnancy and Lactation

Pregnancy

At the time of writing, there are a limited number (11) of exposed pregnancies, none of which indicate any adverse effects on the health of the foetus/neonate.

It is not known if epinastine crosses the placenta, though the molecular weight, low metabolism, moderate plasma protein binding and prolonged elimination half life suggest that this is likely. However, the low systemic bioavailability probably prevents clinically significant amounts from reaching the embryo/foetus. Briggs indicates that a lack of data prevents a complete assessment.

Animal data suggest low risk, and do not indicate any harmful effects with respect to pregnancy, embryonic/foetal development, parturition or postnatal development. At doses several thousand times higher than the maximum recommended ocular human dose, reproductive studies in rats and rabbits have found maternal toxicity, reduced pup body weight gain and resorption and abortion.

The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14-17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( www.toxbase.org ) or if this is unavailable at the backup site ( www.toxbasebackup.org ).

Lactation

It is not known if epinastine is excreted in human breast milk, but it is excreted in rats' milk. Other antihistamines obtaining therapeutic systemic concentrations are classified as compatible with breastfeeding, and Briggs indicates that epinastine be classed similarly.

The molecular weight, low metabolism, moderate plasma protein binding and prolonged elimination half life of epinastine suggest that excretion into human milk is likely, but LactMed concludes that, due to limited absorption from the eye, epinastine would not be expected to cause any adverse effects in breastfed infants.

LactMed also notes a study in which irritability and colicky symptoms were reported in 10% of infants exposed to various antihistamines (route taken unspecified), and drowsiness in 1.6%, none of which were of sufficient severity to require medical attention.

Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
Specialist advice is available from the UK Drugs in Lactation Advisory Service at https://www.midlandsmedicines.nhs.uk/content.asp?section=6&subsection=17&pageIdx=1

Drug excreted in breast milk? - Unknown, but considered likely.

Drug substance licensed in infants? - No.

Other information - Use with caution due to lack of experience, but other antihistamines are considered compatible, and epinastine has low systemic bioavailability.

Effects on Ability to Drive and Operate Machinery

Instillation of eye drops may cause transient blurring of vision. Avoid driving or operating machinery until vision is clear.

Counselling

Advise patient to wash their hands prior to use.

Advise patient to avoid contact of the dropper with the eye or other surfaces as contamination leading to ophthalmic infection may occur.

Advise patients to leave an interval of at least 10 minutes before instilling another ophthalmic medication.

Advise patient to compress the lacrimal sac during administration and for one minute afterwards, to reduce systemic absorption.

Advise patient to remove soft contact lenses before instillation of the eye drops and re-insert them after 15 minutes.

Advise patient to discard eye drops 4 weeks after first opening.

Advise patients that instillation of eye drops may cause transient blurring of vision and to avoid driving or operating machinery until vision is clear.

Side Effects

Blepharoptosis
Conjunctival oedema
Conjunctival hyperaemia
Dry eyes
Photophobia
Visual disturbances
Headache
Asthma
Nasal irritation
Rhinitis
Dry mouth
Taste disturbances
Ocular pruritus
Blurred vision (transient)
Ocular burning
Ocular irritation
Ocular hyperaemia
Ocular discharge
Increased lacrimation
Ocular pain
Dysgeusia

Overdosage

It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

The following number will direct the caller to the relevant local centre (0844) 892 0111

Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( www.toxbase.org ) or if this is unavailable at the backup site ( www.toxbasebackup.org ).

Reference Sources

British National Formulary, 63rd Edition (2012) Pharmaceutical Press, London.

BNF for Children (2011-2012) Pharmaceutical Press, London.

Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 9th edition (2011) ed. Briggs, G., Freeman, R. and Yaffe, S. Lippincott Williams & Wilkins, Philadelphia.

Martindale: The Complete Drug Reference, 37th edition (2011) ed. Sweetman, S. Pharmaceutical Press, London.

Summary of Product Characteristics: Relestat. Allergan Ltd. Revised September 2011.

US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
Available at: https://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT - Record 288 (Epinastine)
Last revised: 04/01/11
Last accessed: 13/06/12