Effective anti-allergy eyedrops now S2

Zaditen (ketotifen), the anti-allergy eyedrops with years of prescription use behind them, have been rescheduled to S2, allowing patients to purchase Zaditen over-the-counter in pharmacies.

Zaditen is indicated for the symptomatic short term treatment of seasonal allergic conjunctivitis (SAC).¹ This is the most common type of ocular allergy, affecting both adults and children.

Although patients can now buy the eyedrops over-the-counter, they may be unaware of Zaditen and will still rely on the recommendation of their healthcare professional, which is why the prescription heritage of Zaditen is so important for doctors, pharmacists and their patients.

Triple-action efficacy

Zaditen is a powerful weapon in the fight against allergy eyes due to its triple action.^1-6

Antihistamine

As a histamine receptor antagonist, Zaditen inhibits the activity of the major chemical mediator involved in type 1 hypersensitivity reactions.⁴

Histamine stimulates the nerve endings and acts as a vasodilator, a stimulant of vascular permeability, a constrictor of vascular smooth muscle and a stimulant of exocrine glands, so it is responsible for some of the key symptoms of SAC.

For patients, the antihistamine activity of Zaditen provides rapid relief from symptoms such as ocular itching and conjunctival hyperaemia.^3,4 It acts within minutes and protects against symptoms for up to 12 hours.^1,7

Mast cell stabiliser

In SAC, mast cells initiate the body’s first immediate reaction to allergens such as pollen.⁵

Zaditen works at both the early-acute and late phase of the hypersensitivity response to act as a mast cell stabiliser, preventing the mast cell from degranulating and releasing inflammatory mediators such as histamine and tryptase. ^1,6

For patients, this mast cell stabilisation activity may help to prevent allergy symptoms from recurring.^1,6

Inhibitor of eosinophil function

Mast cells and eosinophils are known to mediate allergic response over the longer term.⁶ In the late phase of an allergic reaction, there is a huge influx of eosinophils, which play a key role in allergic conjunctival disorders.⁵

Along with its antihistamine and mast cell stabilising actions, Zaditen also inhibits eosinophil chemotaxis, activation and degranulation, and hence the corresponding release of pro-inflammatory cytokines.^1,5

These direct effects on eosinophil function may help to limit the severity of inflammation in the allergic response.⁵

Suitable patients

Zaditen is suitable for the treatment of SAC in children aged three years and above, as well as adults and the elderly.^1,8 It’s available in 5 mL and 2.5 mL bottles, and also in convenient preservative-free single dose units.¹

Patients should be advised to administer one drop in each affected eye twice daily.¹

References

1. Zaditen (Ketotifen) Product Information. North Ryde NSW: Novartis Pharmaceuticals Australia Pty Limited; 27 January 2009.
2. Ganz M, Koll E, Gausche J, Detjen P, Orfan N. Ketotifen fumarate and olopatadine hydrochloride in the treatment of allergic conjunctivitis: A real-world comparison of efficacy and ocular comfort. Adv Ther. 2003; 20(2): 79-91.
3. Abelson MB, Ferzola NJ, McWhirter CL, Crampton HJ. Efficacy and safety of single- and multiple-dose ketotifen fumarate 0.025% ophthalmic solution in a pediatric population. Pediatr Allergy Immunol. 2004; 15(6): 551-7.
4. Sharif NA, Xu S, Yanni JM. Histamine receptor-subtype affinities, selectivities, and potencies of emedastine, a novel H₁-selective antagonist, and other ocularly    employed antihistamines. Drug Dev Res. 2004; 33(4): 448-53.
5. Woerly G, Loiseau S, Loyens M, Schoch C, Capron M. Inhibitory effects of ketotifen on eotaxin-dependent activation of eosinophils: Consequences for allergic eye disease. Allergy. 2003; 58(5): 397-406.
6. Schoch C. In vitro inhibition of human conjunctival mast-cell degranulation by ketotifen. J Ocul Pharmacol Ther. 2003; 19(1): 75-81.
7. Greiner JV, Minno G. A placebo-controlled comparison of ketotifen fumarate and nedocromil sodium ophthalmic solutions for the prevention of ocular itching with the conjunctival allergen challenge model. Clin Ther. 2003; 25(7): 1988-2005.
8. Abelson MB, Chapin MJ, Kapik BM, Shams NB. Ocular tolerability and safety of ketotifen fumarate ophthalmic solution. Adv Ther. 2002; 19(4): 161-9.

(Source: Novartis Consumer Health Australasia Pty Ltd: August 2009)