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Step 10: Over-the-counter versus prescription drugs


Finding the right medication is an important step in treating and controlling allergy symptoms. Over-the-counter (non-prescription) drugs are the most readily available. However, if you go to the allergy aisle in your local pharmacy, you may have trouble deciding which medication is the right one. There are many different formulas and combinations to choose from. See this over-the-counter drugs chart for help.

One goal of allergy drug treatment is to stop the histamine reaction that causes the swelling, itching, and mucus production during an allergic reaction. Therefore, antihistamines are a main ingredient in allergy medications. Here are some generalizations about non-prescription versus prescription antihistamines.

  • Nonprescription -- Many of these are short-acting antihistamines, which relieve mild-to-moderate symptoms. Older antihistamines can cause drowsiness and blunt learning in children (even in the absence of drowsiness). However, several formerly prescription-only antihistamines that don't cause drowsiness are now available over the counter. These do not tend to cause drowsiness or interfere with learning.
  • Prescription -- Prescription antihistamines are usually longer-acting antihistamines. They can be equally effective and usually do not interfere with learning. Other classes of medications such as leukotriene blockers and nasal steroids are also available.


Recent research shows that the effects of some over-the-counter antihistamines (namely diphenhydramine) can impair a person's motor skills as much as, if not more than, alcohol.


Some over-the counter allergy medications also contain a decongestant, which can have a stimulating effect and may raise your blood pressure. You may not feel drowsy even if an antihistamine is affecting your reaction time. Don't drive while taking over-the-counter antihistamines until you know how the medication will affect you.

Cromolyn nasal spray is a gentler over-the-counter medication for treating nasal allergies. Unlike over-the-counter antihistamines, it doesn't blunt learning, memory, and reaction time.

Over-the-counter homeopathic allergy preparations are also available in most drugstores. The benefit of these medications has not been well studied and is best determined on an individual basis. Some homeopathic or herbal preparations may contain natural chemicals that some people should take with caution. Always ask your doctor before taking natural remedies to treat allergies.