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Main > Health > Diseases and Conditions
Print Cite
by Linnea Lundgren and Jeff Wald, MD

Inside This Article
1. 
When Should I Get Medical Treatment for Allergies?
2. 
Allergy Medical Costs
3. 
Selecting a Doctor
4. 
Visiting a Doctor
5. 
A Guide to Allergy Tests
6. 
Choosing an Allergy Medication
7. 
Allergy Nasal Sprays, Skin and Eye Treatments
8. 
Allergy Shots
9. 
See all Diseases and Conditions articles

Choosing an Allergy Medication

Allergy medicines can be nonprescription or prescription drugs, expensive or reasonably priced, fast-acting or time-released. They come in pill, capsule, liquid, and nasal spray forms. New drugs seem to arrive on the shelves almost monthly, while established drugs sometimes are removed from the market after they're belatedly found to have dangerous side effects.

Allergy Terms to
Know Definitions
Histamine: A compound released by cells of the immune system in an allergic reaction. Characteristics of histamine release include, but aren't limited to, itching, sneezing, runny nose, stimulation of stomach secretions, dilation (expansion) of blood vessels, increased mucus secretion, decrease in blood pressure, and contraction of airway muscles.

Antihistamine: A drug used to counteract histamine by blocking the binding of histamine to its receptors.

Antihistamines

Antihistamines are the primary and first line of defense against allergy symptoms, such as sneezing, runny nose, and itchy eyes and throat. They have a long track record, more than 50 years, and have proved to be effective at controlling allergy symptoms, particularly when begun before symptoms start.

Antihistamines work by preventing histamine, a chemical that is a main player in the body's allergic response, from binding to its receptor. Antihistamines are less effective after symptoms are present but can still temporarily diminish their severity. Some antihistamines work quite well even after symptoms are present. However, they can lose their effectiveness if used daily for long periods of time.

Over the Counter or Prescription?  

Allergy sufferers often turn to over-the-counter (OTC) medications first. That's because they're readily available at any drugstore and don't require a visit to the doctor. There's nothing inherently wrong with using an over-the-counter product. But there are several important considerations.

At-Work Risks
and Antihistamines
A clinical study conducted by the Group Health Cooperative of Puget Sound found that people on OTC sedating antihistamines are 50 percent more likely to have a work-related accident than people on non-sedating antihistamines.

First of all, over-the-counter antihistamines are for temporary use and should never be self-administered as part of your own long-term allergy treatment program. Even limited use can cause side effects. Some over-the-counter antihistamines are sedating, meaning that they cause drowsiness and slow your reflexes, impairing your ability to drive, operate heavy machinery, or participate in any activity that requires quick reflexes. Alcohol can aggravate these effects. Other side effects include dry mouth, dry sinuses, dry eyes, and stomach upset.

Second, while antihistamines work like linebackers, blocking histamines trying to cause an allergic touchdown, OTC antihistamines often come with their own referee: a decongestant (listed as pseudoephedrine on the label). Decongestants help unstuff problem areas, mainly the nose, but they come with their own set of side effects, too, including nervousness, insomnia, elevated blood pressure, heart palpitations, and for men, prostate problems. While some believe these side effects offset the drowsiness caused by the antihistamine, they can be dangerous, particularly if you have a preexisting medical condition. Most doctors recommend using only single-ingredient products. If you're sneezing and itching, use an antihistamine. If you're all clogged up, use a decongestant for a day or two. (And always be sure to read and follow package directions.)

How to Choose an OTC Antihistamine

It's best to go to the drugstore as an informed consumer so you can make the best choice in an OTC antihistamine. Here's how the name brands differ from one another:

Medication Interaction
Warning
Popping pills indiscriminately can open up a can of worms, or in the worst-case scenario, it can open up a coffin lid for you. Always read the labels of OTC and prescription medicines to check for drug interaction precautions. When talking to a doctor, list all medications and supplements you use -- OTC, prescribed, herbal, homeopathic. (It helps to write them down.) Should any doubts or uncertainties exist, pick up the phone and call your pharmacist or doctor. A quick check could save you from a life-threatening experience.

  • Chlor-Trimeton and Dimetapp belong to the alkylamine family, which are not too sedating or drying.
  • Benadryl and Tavist belong to the ethanolamine family and are very sedating and drying.
  • Actifed belongs to the piperadine family and is less sedating but somewhat drying.
  • Claritin (loratidine) is non-sedating and is not drying.
When selecting and using an OTC antihistamine, follow these guidelines:
  • Read the labels and follow all directions.
  • Do not exceed the recommended dosage.
  • Do not take them for a prolonged period of time.
  • Consult the pharmacist and check for any drug interactions with your chosen product.
  • Focus on your symptom and buy a drug designed to treat that symptom. Drugs that attempt to relieve every symptom can expose you to unnecessary medications and risks.

    Overuse of
    Nasal Sprays
    O    ver-the-counter decongestant nasal sprays (Afrin, Neo-Synephrine, Otrivin, Duration Nasal Spray, etc.) should only be used for short-term (as in two to three days) symptom relief. Use them for a longer period and you might suffer a nasty rebound effect. In addition, used too long, these medicines lose their effectiveness. Not only that, but overuse can irritate and inflame the mucous membranes in your nose, making you more congested than ever. If you experience rebound, you'll be tempted to squirt more stuff up your nose. Resist the urge, or you'll start a vicious cycle of congestion. Always abide by the warning labels of OTC nasal sprays and stick to the time-use limitations.

  • Be especially careful if you're a senior citizen. Elderly people are more susceptible to side effects of antihistamines and may suffer blurred vision, light-headedness, dry mouth, confusion, and drowsiness.
  • Do not take OTC antihistamines if you have breathing problems, heart problems, high blood pressure, diabetes, glaucoma, prostate gland problems, difficulty urinating, peptic ulcer, or liver or kidney damage. Women who are pregnant or nursing should always consult their physician before taking any drug.
  • For a quick solution to short, seasonal suffering, OTC antihistamines help relieve symptoms. However, if they don't sufficiently lessen your symptoms or if the side effects increase your suffering, consult a doctor for long-term solutions.
Prescription Antihistamines

Many prescription antihistamines are non-sedating, work longer and faster, and have fewer and less noticeable side effects than their drugstore siblings. Those benefits mean that prescription antihistamines, particularly those called "second generation antihistamines" such as Allegra (fexofenadine), Clarinex (desloratadine), and Zyrtec (cetirizine), are generally safer to use and will fit better with your lifestyle because you'll have to take them only once or twice a day. Allegra, Clarinex, and Zyrtec come as single-ingredient products or in combination with decongestants.

The benefits of prescription antihistamines can come at a cost, as they sometimes are more expensive than their OTC counterparts.

However, some prescription antihistamines, such as Allegra and Flonase, are available as generics and are less expensive. Since you'll need fewer pills if you're taking a prescription antihistamine, they may not be quite as expensive, comparatively, as they first seem. And if you have prescription-drug insurance, some or all of the cost may be covered.

Astelin, a prescription antihistamine nasal spray, is one of the newest forms of allergy treatment. It reduces the symptoms of allergic rhinitis without drowsiness and without many side effects. It is another therapeutic option.

There are other allergy treatments than just prescription medication. Among them are nasal sprays, skin treatments and eye drops. We will take a look at all three in the next section.

Driving and Antihistamines
Don't think drunk drivers are the only danger on the road. Ordinary allergy sufferers who take OTC antihistamines can be just as dangerous, according to a study reported in the Annals of Internal Medicine. (The study was funded by research organizations and pharmaceutical companies.)

The study concluded that taking the recommended dosage of OTC antihistamines (notably ones containing diphenhydramine, such as Benadryl) could impair a person's driving ability even more than being legally drunk. A more alarming outcome of the study, however, was the fact that those taking OTC antihistamines didn't feel drowsy or impaired. Self-assessment, then, is no indicator of drowsiness.

What does this mean to the poor allergy sufferer? Never drive while using OTC antihistamines, even if you feel alert. Not only are you a danger to yourself and others, but you may also be slapped with a DUI (driving under the influence) ticket if pulled over. Laws differ from state to state, but many DUI laws apply to drivers impaired by OTC medications used to treat allergies and cold symptoms.

This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.

The brand name products mentioned in this publication are trademarks or service marks of their respective companies. The mention of any product in this publication does not constitute an endorsement by the respective proprietors of Publications International, Ltd. or HowStuffWorks.com, nor does it constitute an endorsement by any of these companies that their products should be used in the manner described in this publication.
 
Inside This Article
1. 
When Should I Get Medical Treatment for Allergies?
2. 
Allergy Medical Costs
3. 
Selecting a Doctor
4. 
Visiting a Doctor
5. 
A Guide to Allergy Tests
6. 
Choosing an Allergy Medication
7. 
Allergy Nasal Sprays, Skin and Eye Treatments
8. 
Allergy Shots
9. 
See all Diseases and Conditions articles

 


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