Medical Edge Newspaper Column

Avoiding allergens may beat allergy medicine effects

June 20, 2008
Dear Mayo Clinic:
My wife bought an allergy medicine for me last spring when my allergies flared up. It worked well in reducing nasal symptoms, but it seemed to make urinating even more difficult for me than it usually is. Is there some other medication I can try?

Answer:
Yes, there is. But first, if you have difficulty urinating — such as hesitancy, slow stream or incomplete emptying — at times other than when you're taking the medication, talk to your doctor. This could be an indication of another problem, such as an enlarged prostate.

Apart from that, many nonprescription allergy medications — including those containing diphenhydramine (Benadryl, others), chlorpheniramine maleate (Actifed, Chlor-Trimeton, others) and dexbrompheniramine maleate (Drixoral, others) — are within a class of medications that are often referred to as first-generation antihistamines.

The most well known side effect of these drugs is drowsiness. However, additional side effects include drying of the eyes and mouth, and difficulty urinating. These side effects are often more pronounced in older adults, especially in men and in those who already have difficulty urinating.

You should be able to lessen most of those side effects by taking an allergy medication that belongs to the so-called "second generation" class of antihistamines. These include loratadine (Claritin, others) and cetirizine (Zyrtec) — which are available as nonprescription drugs — and fexofenadine (Allegra).

In addition, you may want to talk to your doctor about strategies for avoiding allergy triggers and about additional therapies. These may include steroid nasal sprays, which are considered quite safe and are often more effective than using antihistamine drugs for relieving allergy-related nasal inflammation and irritation.

— James Li, M.D., Ph.D., Allergic Diseases, Mayo Clinic, Rochester, Minn.