Article Date: 3/1/2002

Allergy Update
ALLERGY UPDATE

How Do You Spell Relief?
What's the best way to help your allergy patients cope with their problem? This month, the experts weigh in with advice.

Fighting Back
What you can use to relieve your patients' allergic eyes.
BY DEEPAK GUPTA, O.D., F.A.A.O.,
Stamford, Conn.

Treating patients who come to you with itchy, watery eyes can be challenging. A long list of potential medications and coexisting medical conditions can cloud the diagnostic picture. Let's review some of the finer points of diagnosing seasonal allergies and get updated on the latest in medical treatment.

Is it allergy?

You first need to rule out other reasons for these patients' red, irritated eyes. Look for:

Because the signs of allergy that you observe at the slit lamp can be minimal, it's especially important to take a thorough history. One of the key complaints in allergic conjunctivitis is itching, which may be accompanied by redness, chemosis, tearing and lid swelling. One basic guideline often holds true: "If it itches it's allergy, if it burns it's dry eye and if it's sticky it's bacterial."

Patients who just have dry eye don't have itching. Patients who have seasonal allergies rarely demonstrate the discharge associated with bacterial conjunctivitis. Patients who just have blepharitis have some intermittent itching, but it isn't the predominant symptom.

When ruling out hypersensitivity reactions, remember that many eye drops, including some glaucoma medications, contain a benzalkonium chloride preservative that can cause toxicity reactions. In addition, contact lens wearers may have allergic reactions to the solutions or to the lenses themselves. To eliminate these possible culprits, have the patient temporarily discontinue contact lens use and see if the symptoms resolve.

Treating allergy

There are 14 types of eye drops that fall into five pharmacological classes of drugs for ocular allergy. This broad range of options should allow you to treat individual patients according to their specific ailments and lifestyles. As a review, the five classes and 14 drops are:

1 Topical antihistamines. These agents combat redness and swelling as well as itch. They have little impact on other pro-inflammatory mediators, such as prostaglandins and leukotrienes but provide short-term, rapid symptomatic relief of itch. Topical antihistamines include:

2 Topical mast cell stabilizers. These medications prevent mast cell degranulation. They don't relieve existing symptoms of allergy; they prevent them from occurring. The patient must take them regularly and prophylactically before actually having a problem. Topical mast cell stabilizers include:

3 Topical antihistamines/mast cell stabilizers. These dual-acting compounds are excellent for treating ocular allergy because they combine the fast response of antihistamines with the prolonged action of mast cell stabilizing activity. Topical antihistamines/mast cell stabilizers are:

4 Topical NSAIDs. Nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit the cyclooxygenase pathway causing a decrease in the production of prostaglan-dins and thromboxane. Consequently, the itchiness of allergic conjunctivitis decreases. NSAIDs can delay corneal wound healing and patients must take them q.i.d. Topical NSAIDs include:

5 Topical corticosteroids. Because of potential side effects, you should only prescribe topical steroids when severe allergic conjunctivitis doesn't respond to other treatment modalities. Try a mild steroid with a good safety and efficacy profile, such as loteprednol, or prescribe a stronger steroid to initially decrease symptoms and then switch over to a combination mast cell stabilizer/antihista-mine. Topical corticosteroids include:

The new kids on the block

Mast cell degranulation on the conjunctiva causes the clinical symptoms of allergy. A cascade of events results, leading to increased levels of histamine on the ocular surface. Drugs known as mast cell stabilizers reduce the amount of degranulation and histamine that the mast cells release. Antihistamines act against histamine, which has already been released.

For symptomatic relief of acute, mild hay fever conjunctivitis, an antihistamine may prove effective. But patients who have chronic ocular surface allergy need to stabilize their mast cells long term.

Four medications, introduced in the past 2 years, can help combat the symptoms of allergic conjunctivitis. They are:

Why You Should Treat
Seasonal Allergies

Patients rely on you to properly diagnose and manage their conditions. Do this properly and you gain their trust. Not only will these patients be more likely to return to you for future visits, but they'll be more likely to refer a friend or relative to your office. Here are some tips:

Whenever you write a prescription for an allergy medication, schedule the patient for a follow-up visit to make sure that the problem is under control.

By treating seasonal allergies as a legitimate medical condition, you can fill a niche that many ophthalmologists have abandoned. In their haste to gather patients for surgery, they tend to regard complaints of itchy eyes as a nuisance. That's where you can step in and demonstrate your expertise as a primary eyecare provider.

 

Pemirolast. This mast cell stabilizer treats allergy by inhibiting the antigen-induced release of inflammatory mediators from human mast cells. It also prevents the chemotaxis of eosinophils into ocular tissue. Although it's fairly effective against itch, it can take several weeks to take effect. Pemirolast is best for seasonal allergy sufferers who can take the drug prophylactically. It's currently recommended for q.i.d. dosing.

Nedocromil. This mast cell stabilizer works relatively well at relieving itching caused by allergic conjunctivitis. Its b.i.d. dosing is adequate for patient compliance. Like pemirolast, it can take a couple of weeks for the patient to attain relief.

Be aware that this drug seems to have a high number of adverse reactions. For example, 40% of patients taking this drug experience headaches, and another 10% to 30% complain of ocular burning and stinging, unpleasant taste and nasal congestion. These adverse reactions can cause a patient to discontinue therapy.

Azelastine. This H1 antagonist inhibits the release of histamine and other cell mediators involved in the allergic response. There's some evidence that it also helps stabilize mast cells. The dosing for azelastine is b.i.d.

Ketotifen. This is an excellent combination mast cell stabilizer and antihistamine. Unlike some other drugs in its class, it offers true b.i.d. dosing -- one drop lasts 12 hours instead of 8. This long duration of action is especially nice for contact lens wearers. There's a slightly higher rate of burning/stinging upon instillation, however.

Over-the-counter drugs

A few over-the-counter (OTC) medications manage seasonal allergic conjunctivitis. Most are simple antihistamines combined with vasoconstrictors, such as naphazoline (e.g., Naphcon, VasoClear, Allerest, etc.). However, they don't adequately manage the condition and can cause rebound redness, leaving the eyes chronically red.

Oral medications

The alternative is oral medications. Some of the more popular drugs include diphenhydramine HCl (Benadryl), fexofenadine HCl (Allegra), loratadine (Claritin) and cetirizine HCl (Zyrtec). However, many of them have poor ocular penetration. I use them more to control systemic conditions when I think eye drops alone won't properly manage a patient's ocular symptoms.

The best is yet to come

The future will undoubtedly bring new and potent anti-allergic medications with a broad spectrum of therapeutic characteristics. Current research focuses on therapeutic agents such as binding proteins, which are naturally secreted by some insects to combat the host's immune system. We also use immunoglobulin (IgE) blockers as anti-allergy medications.

As primary eyecare providers, we owe it to ourselves and to our patients who suffer from allergies to keep up with these new advances in treatment.

References available upon request.

Dr. Gupta has no financial interests in any of the companies or products mentioned in the article. Reach him at deegup4919@hotmail.com.

 

Allergies Around the U.S.
A peek at what your colleagues in different regions are doing to treat patients suffering from allergies.
BY TERRI B. GOSHKO, Senior Associate Editor

If you're like most O.D.s, you see plenty of allergy patients. And if that's the case, have you ever wondered how your treatment approach compares to those of your peers around the country? This month, we'll take a look at what our experts are doing to treat allergy patients.

QUESTION: How do you incorporate drugs into practice?

Dr. Thimons: Prescription intervention for allergy patients is one of the mainstays of primary eyecare practice. The increase in patients who report symptoms, and the increased public awareness of allergy promoted by direct-to-consumer marketing has created an opportunity for us to direct therapeutic intervention to treat patient symtomatology.

J. James Thimons, O.D., F.A.A.O., is from Ophthalmic Consultants, a multi-specialty surgical practice, and TLC Laser Center in Fairfield, Conn. He's also Optometric Management's clinical director.

The mainstays of allergy therapy are the multiphasic antihistamine/mast cell-stabilizing agents that dominate the allergy treatment scene. These include pemirolast potassium (Alamast), olopatadine HCl (Patanol), nedocromil sodium (Alocril), ketotifen fumarate (Zaditor), loteprednol etabonate (Alrex), and azelastine HCl (Optivar). They've revolutionized management because of their simplicity, better rate of patient compliance and efficacy.

In our practice, we use the multiphasics as our initial line of therapy in most patients.

Patients now look to us for their clinical allergy treatment. We often have them return in advance of their noted allergy season and initiate therapy ahead of time, significantly decreasing clinical presentation. Multiphasic agents alone can control most patients' symptomatic allergic response. Sometimes we'll add a topical steroid to the multiphasic, which completely alleviates symptoms while concurrently treating with an antihistamine/mast cell stabilizer, so that when we discontinue steroid use, the symptoms still will be well managed.

Dr. Bowling: Before incorporating allergy drugs into your practice, make sure you take a patient history. Include questions about ocular allergy in your patient questionnaire. Ask patients about allergy symptoms during the interview even if they aren't experiencing any at the time of exam.

Ernie Bowling, O.D., M.S., F.A.A.O., practices in Summerville, Ga. He's a member of Optometric Management's editorial board, a multiple recipient of the AOA Optometric Recognition Award and is a clinical examiner with the National Board of Examiners in Optometry

The hallmark symptom is itching. I once heard a speaker say, "If it itches, then it's allergy."

Eliminating or controlling the offending agent (if it's known) is the first step. I also like what I call "Grandma's home remedy," a cold compress or ice pack to reduce redness and swelling.

The first step of topical therapy is an artificial tear. Artificial tears will help wash out the offending antigens and restore the normal tear composition. I prefer non-preserved tears in these cases, to prevent adding another potential allergen to the eye.

I use prescription medications depending upon the severity of the presentation. I'll use a mild topical steroid such as loteprednol for severe allergic conjunctivitis. They quiet the inflammation and make the patient comfortable quickly. Coordinate steroid use with appropriate patient education regarding the short-term nature of steroid use and the potential side effects.

Once the patient gets over the initial insult, I prescribe something for long-term maintenance. I like using the mast cell combinations such as olopatadine and ketotifen.

Dr. Karpecki: My allergy regimen depends on the symptoms and the severity of clinical signs. For seasonal allergic conjunctivitis, I use mast cell stabilizers, antihistamine/mast cell stabilizer combination drops, steroid drops and oral antihistamines.

Paul Karpecki, O.D., graduated from Indiana University School of Optometry and completed a fellowship in Cornea and Refractive Surgery at Hunkeler Eye Centers in 1994. He serves as an industry consultant and is involved in an extensive portfolio of ophthalmic activities. He's also on the editorial board of Optometric Management.

First, I recommend cool compresses and preservative-free artificial tears for all patients who present with seasonal allergic conjunctivitis. Also have the patient place the allergy drops in the fridge. Cool drops soothe as the medication begins to work.

For consistent yearly seasonal allergic conjunctivitis, I recommend mast cell stabilizers, starting b.i.d. 2 to 4 weeks before the anticipated allergy attack. Mast cell stabilizers such as nedocromil or pemirolast b.i.d. appear to work well.

For mild to moderate acute allergic conjunctivitis with no systemic symptoms but with itching specific to the eye (usually moderate), the clinical signs are critical to determining treatment. If there's mild erythema or redness and edema, I prefer combination mast cell stabilizer/antihistamine drops such as olopatadine, azelastine or ketotifen b.i.d.

In moderate cases with edema, erythema or sever allergic conjunctivitis, I prefer steroids. Two of the most effective drops are loteprednol 0.2% (Alrex) and loteprednol 0.5% (Lotemax); they're fast acting and less likely to cause side effects compared to other steroid drops. In cases where the patients say the allergic conjunctivitis affects their ability to function, I prescribe soft steroids such as Alrex b.i.d. for 2 weeks.

For moderate acute allergic conjunctivitis with systemic symptoms, I add oral antihistamines to the topical medications mentioned earlier. Symptoms include allergic rhinitis or itchy, runny nose, itchy throat or cough or allergic sinus congestion. Loratadine (Claritin) or fexofenadine (Allegra) q.d. are good, non-sedating oral antihistamines. Keep in mind that non-sedating doesn't mean non-drying, so these patients must continue or even increase the use of artificial tears. For allergic sinus congestion, I prescribe Claritin-D 24 hour or Allegra-D 24 hour, which contains the decongestant pseudoephedrine.

Dr. Onofrey: The cornerstone of my approach to managing ocular allergy is proper staging of the disease. I'm particularly interested in knowing if it's a seasonal or perennial allergy, how severe the symptoms are, whether there's a significant inflammatory component and how the patient has treated the condition in the past.

Treatment always begins with artificial tears. This debulks the antigen and provides a measure of immediate relief.

Bruce E. Onofrey, O.D., R. Ph., F.A.A.O. is responsible for primary eyecare services at Lovelace Medical Center, Montgomery Eye Clinic in Albuquerque.

Next, I add a multi-action antihistamine/mast cell inhibiting topical agent such as olopatadine, azelastine or ketotifen.

If nasal symptoms are present, I also prescribe a nasal steroid such as fluticasone propionate (Flonase) or a nasal mast cell inhibitor such as cromolyn sodium (Nasalcrom). I prefer not to use systemic antihistamines initially because of their anticholinergic side effects.

If I do prescribe an oral medication, I prefer fexofenadine. The dosage is titratable (30 mg to 60 mg once or twice daily or once daily with the 180 mg sustained-release dose). Fexofenadine is also available with a decongestant (Allegra-D).

For difficult cases or those with inflammation, I use topical loteprednol; it's the only topical steroid the FDA approved for allergy.

Follow these tips for treating allergy:

 


Optometric Management, Issue: March 2002