. . . WHEN FACED WITH TREATING ALLERGIES
IN RECENT years, we have seen elevated pollen counts, which are a great nuisance to our patients who suffer from allergies. So, what’s the most effective way to enable these and other allergy patients to achieve relief?
Allergic conjunctivitis management is usually achieved with a staged approach, with topical antihistamines being front-line therapy and then using more aggressive treatments, or stacking therapies, if you see the clinical need to do so.
Here, I provide this staged approach, as well as other treatment considerations.
STAGE 1: ARTIFICIAL TEARS
These work to clear allergens from the ocular surface and tear film and provide additional lubrication and comfort.
Dry eye disease (DED) and allergic conjunctivitis, while unrelated, have inflammatory etiologies and can, therefore, worsen each other, in terms of symptoms, such as itching, burning and foreign body sensation. Remember, DED patients have less aqueous tear production and, thus, have delayed clearance of allergens, which compounds the allergic problem.
|Other chronic allergic conjunctivitis||H10.45|
|Unspecified acute conjunctivitis||H10.3|
|Acute atopic conjunctivitis||H10.1|
|Unspecified chronic conjunctivitis||H10.40|
STAGE 2: OTC ANTIHISTAMINES
My thought is that if you have a patient in your chair who came to your office and you diagnose them with allergic conjunctivitis, you should prescribe a therapeutic. The reason: These patients have often tried OTC options and self-treated with no relief, so they’re seeing you.
That said, non-prescription options can alleviate mild symptoms and signs. Some caveats regarding usage: They are less efficacious, having lower affinities for histamine receptors, have shorter duration of action and don’t prevent mast cell degranulation, which releases inflammatory mediators, such as histamine, contributing to allergy symptoms. In addition, OTC antihistamines often require frequent dosing, which can create more irritation and side effects, such as worsening punctate keratitis due to the frequent use of toxic preservatives. Bottom line: When prescribing these, less is more, when compared with the newest prescription topical therapies that offer q.d. or b.i.d. dosing.
STAGE 3: PRESCRIPTION DRUGS
Most of the latest ocular therapeutics for allergic conjunctivitis act by blocking H1 and H2 receptors. They decrease the amount of allergens that bind to mast cells, causing mast cell degranulation to reduce the release of allergic mediators. Many work as fast as three minutes and, in most patients, they provide relief for as long as 24 hours.
STAGE 4: TOPICAL STEROIDS
These are ideal for patients who have more severe allergic symptoms that cannot be controlled by the above management options alone. You want to prescribe short-term use of topical steroids (b.i.d. to q.i.d. for two to four weeks) for allergies, using low-concentration corticosteroids, which have a lower propensity to cause side effects, such as elevated IOP. (See “Future Treatments,” right.)
Future therapies aim to have a fast onset of action, being highly efficacious with a good safety profile. Most recently, the FDA approved cetirizine ophthalmic solution 0.24% (Zerviate, Nicox), which is a second generation antihistamine (H1 receptor antagonist). It works by binding to histamine receptor sites to reduce itching, swelling and vasodilation. This is an antihistamine indicated to treat ocular itching associated with allergic conjunctivitis. The drug significantly reduced ocular itching compared to placebo at 15 minutes and eight hours after treatment and is dosed b.i.d.
In a perfect world, all contact lens patients who have allergies would wear daily disposable contact lenses because this option gives patients a fresh, new lens every single day, which decreases allergen build up. To prevent contact lens dropout in seasonal allergy patients, you want to pre-treat these patients with a topical antihistamine prior to allergy season.
Another consideration: If a DED patient wearing punctal plugs has allergies, consider removing the plugs during allergy season. This might sound counter intuitive, but it can be a great short-term treatment option to increase drainage and the clearance of the tear film from allergens.
SETTING THE STAGE
Allergies can greatly affect our patients, especially those who wear contact lenses or who suffer from DED. As a result, we must be vigilant and proactively follow the stages outlined above with an eye on prescribing modern therapeutics that have greater efficacy compared with OTC options. Doing so will help prevent the seasonal misery affecting a fairly large percentage of our patients. Finally, instead of just prescribing, consider educating patients on why you are prescribing a specific therapy, as doing so can increase patient compliance, while instilling in patients your value as their eye care provider. OM