Zaditor

Ocular Anti-Allergics, Antihistamines

Ophthalmic Solution
Ketotifen is for topical ophthalmic use only. Do not give by injection or orally.
Wash hands before and after use. Tilt the head back slightly and pull the lower eyelid down with the index finger. Squeeze a drop into the conjunctival sac and gently close the eye and apply pressure for 1 to 2 minutes over the point where the lid meets the nose. If more than one drop it to be administered, wait 3 to 4 minutes before instilling another drop into the same eye.
Care should be taken to avoid contamination. Do not touch the tip of the dropper to the eye, fingertips, or other surface.
If multiple ophthalmic medications are to be administered, wait at least 5 to 15 minutes before delivering a second medication to the same eye to prevent dilution.
Patients should wait at least 10 minutes after instilling the ophthalmic solution before inserting contact lenses.
Do not share ophthalmic drops between patients.
 
Drug-eluting Contact Lenses with Ketotifen
When initiating treatment, ensure the patients is able to insert the lenses and remove them (or have someone else available who can remove the lenses) before leaving the eye care professional's office.
Inserting lenses:
The lenses should not be inserted onto red or irritated eye(s).
Ensure hands are clean, dry, and free of any soaps, lotions, or creams before handling the lenses. It is best to put on the lenses before applying makeup.
Each multi-pack contains individually packaged lenses. Confirm the lens parameters printed on the multi-pack and the individual lens matches the prescription. Store individual blister packages in the carton at room temperature until use, as lenses are light sensitive. DO NOT use if the blister package is opened or damaged.
To open an individual lens package:
Shake the package and check to see that the lens is floating in the solution.
Peel back the foil closure.
Place a finger on the lens and slide the lens up the side of the bowl of the package until it is free of the container. NEVER use tweezers or other tools to remove the lenses.
Handle the lenses with the fingertips, and avoid contact with fingernails.
Always work with the same lens first to avoid mix-ups.
After removal from the packaging, examine the lens to ensure it's free of any nicks or tears. DO NOT use if the lens appears damaged.
To ensure the lens is not inside out:
Place the lens on the tip of the index finger and check its profile. If the lens edges point outward, it is inside out.
Gently squeeze the lens between the thumb and forefinger. The edges should turn inward. If the lens is inside out, the edges will turn outward. An alternate method is to locate the numbers 1-2-3 on the lens. If the numbers are listed as 1-2-3, then the lens is in the correct orientation. However, if the numbers are reversed, then the lens is inside out.
With the lens on the index finger, use the other hand to hold the upper eyelid.
Pull down the lower eyelid with the other fingers of your inserting hand.
Look up at the ceiling and gently place the lens on the lower part of the eye.
Slowly release the eyelid to close the eye for a moment. Blink several times to center the lens.
Removing lenses:
Always be sure the lens is on the cornea (center of the eye) before attempting to remove.
Wash, rinse, and dry hands thoroughly.
Pinch method:
Look up, slide the lens to the lower part of the eye using the forefinger.
Gently pinch the lens between the thumb and forefinger.
Remove the lens
If the lens sticks, a few drops of saline solution may be applied directly to the eye to assist with removal. Consult an eye care professional if non-movement of the lens continues after a few minutes.
Never wear the lenses beyond the amount of time recommended by the eye care professional. Wear only 1 pair of lenses per day. Lenses are single use only; throw away worn lenses. No cleaning or disinfection is needed.
Do not apply eye drops containing benzalkonium chloride while wearing the lenses. Wait 10 minutes after applying eye drops with benzalkonium chloride before inserting or reinserting lenses.
Never share the lenses with someone else.

keratitis / Delayed / 0-5.0

conjunctival hyperemia / Early / 10.0-25.0
photophobia / Early / 0-5.0
conjunctivitis / Delayed / 0-5.0

headache / Early / 10.0-25.0
rhinitis / Early / 10.0-25.0
lacrimation / Early / 0-5.0
pruritus / Rapid / 0-5.0
rash / Early / 0-5.0
mydriasis / Early / 0-5.0
xerophthalmia / Early / 0-5.0
pharyngitis / Delayed / 0-5.0
ocular discharge / Delayed / 0-5.0
ocular irritation / Rapid / 1.0
ocular pain / Early / 1.0

Alaway, Children's Alaway, Claritin Eye, Eye Itch Relief, Itchy Eye, Zaditor, Zyrtec Itchy Eye

OTC

Ophthalmic antihistamine available as an opthalmic solution and a drug-eluting contact lens
Prevents ocular pruritus due to allergic conjunctivitis; the drug-eluting contact lens also corrects refractive ametropia (myopia and hyperopia) in aphakic or phakic patients
The drug-eluting contact lenses are contraindicated in patients with corneal infection, decreased corneal sensation, or ocular hyperemia

1 drop in the affected eye(s) twice daily at an interval of 8 to 12 hours.

1 drop in the affected eye(s) twice daily at an interval of 8 to 12 hours.

Insert 1 lens per eye per day. The effectiveness in preventing ocular pruritus lasts through 12 hours; however, the lenses may be worn beyond 12 hours for vision correction. The maximum daily wear time should be determined by the eye care professional based upon the patient's individual response to contact lenses. Lenses should be removed prior to sleeping and discarded after a single day's use.

Insert 1 lens per eye per day. The effectiveness in preventing ocular pruritus lasts through 12 hours; however, the lenses may be worn beyond 12 hours for vision correction. The maximum daily wear time should be determined by the eye care professional based upon the patient's individual response to contact lenses. Lenses should be removed prior to sleeping and discarded after a single day's use.

No dosage adjustments are needed.

No dosage adjustments are needed.

There are no drug interactions associated with Ketotifen products.

Alaway/Children's Alaway/Claritin Eye/Eye Itch Relief/Itchy Eye/Ketotifen/Zaditor/Zyrtec Itchy Eye Ophthalmic Sol: 0.025%

2 drops per affected eye per day for ophthalmic solution; 1 lens per eye per day for drug-eluting contact lenses with ketotifen.

2 drops per affected eye per day for ophthalmic solution; 1 lens per eye per day for drug-eluting contact lenses with ketotifen.

2 drops per affected eye per day for ophthalmic solution; 1 lens per eye per day for drug-eluting contact lenses with ketotifen.

11 years and older: 2 drops per affected eye per day for ophthalmic solution; 1 lens per eye per day for drug-eluting contact lenses with ketotifen.
3 to 10 years: 2 drops per affected eye per day for ophthalmic solution; safety and efficacy not established for drug-eluting contact lenses with ketotifen.
younger than 3 years: Safety and efficacy have not been established.

Safety and efficacy have not been established.

Safety and efficacy have not been established.

Ketotifen, a benzocycloheptathiophene derivative, is a histamine-1 (H1) receptor antagonist. Following topical administration to the eye, ketotifen stabilizes mast cells and prevents eosinophil accumulation which blocks the onset of ocular allergic pruritus. For the drug-eluding contact lens product, the lens acts as a refracting medium to focus light rays on the retina in order to correct refractive ametropia for as long as the lens is worn (up to 24 hours while awake).

Ketotifen is administered topically to the eye as an ophthalmic solution or a drug-eluding contact lens. In oral administration studies, circulating ketotifen was 75% bound to plasma proteins. Orally administered ketotifen has an absolute bioavailability of 50% due to extensive first pass metabolism. Ketotifen underwent glucuronidation to the inactive metabolite ketotifen-N-glucuronide and demethylation to nor-ketotifen, which has similar activity as the parent compound. These metabolites are recovered in the urine and account for 50% and 10% of an orally administered dose, respectively. The distribution and elimination half-lives following oral administration of ketotifen are 3 hours and 22 hours, respectively.
 
Affected cytochrome P450 isoenzymes and/or drug transporters: none

Ophthalmic Route
Ketotifen is not absorbed systemically following ocular administration.
Ophthalmic solution: Ketotifen has a rapid onset of action with an effect observed within minutes following administration. Ketotifen has been shown to have little systemic exposure following ocular administration. In healthy volunteers treated bilaterally with ketotifen ophthalmic solution twice daily for 14 days, plasma concentrations were generally below the quantitation limit of the assay (less than 20 pg/mL).

No adequate and well-controlled studies have been conducted to evaluate the use of ophthalmic ketotifen (as the drug-eluting contact lenses or ophthalmic solution) during pregnancy in humans to inform a drug-associated risk; however, ketotifen is not absorbed systemically following ocular administration, and maternal use is not expected to result in fetal drug exposure. In animal studies, oral administration of ketotifen to pregnant rats and rabbits did not produce teratogenicity at clinically relevant doses.

There are no data available regarding the presence of ketotifen or its metabolites in human milk. It is not known if topical ocular administration could result in sufficient systemic absorption to produce detectable quantities of the drug in breast milk. Consider the development and health benefits of breast-feeding, the mother's clinical need for the drug, and any potential adverse effects on the breast-fed infant from ketotifen.