Over the Counter Allergy Medications, Part I

Medications Taken Orally

This post provides basic information to consumers on over-the-counter (OTC) oral medicines for the treatment of common allergies, such as seasonal allergy and allergic rhinitis.

It is my hope that the information, highlighting similarities and differences among various products, will help consumers in choosing a product best suited for their need.

ALL information is intended solely for informational and educational purposes, and NOT to be taken as medical advice.

Even though OTC-medications are available without a prescription, readers are strongly urged to consult an appropriate licensed health care provider before using them.

Note: Part II of OTC Allergy Medications will cover eye drops and nasal sprays used to relieve eye/nose symptoms associated with common allergies.

KEY POINTS

I. Some of the common brand names are:

Alavert            

Allegra 

Benadryl 

Claritin  

Xyzal  

Zyrtec  

II. Most common oral otc-allergy medicines have one of the following active ingredients:

Cetirizine (se-tir-a-zeen)

Chlorpheniramine (klor-fen-ir-a-meen)

Diphenhydramine (dahy-fen-hy-druh-meen)

Fexofenadine (fex-oh-fen-a-deen)

Levocetirizine (lee-voe-se-tir-a-zeen)

Loratadine (lor-at-a-deen)

III. All these active ingredients are antihistamines and reduce the symptoms of common allergies by blocking the effect of histamine, a chemical released in tissues in response to an allergen, such as pollen.

Among the antihistamines listed above, chlorpheniramine and diphenhydramine are older and classified as sedating, while others are newer and classified as non-sedating.

In many products, an antihistamine is combined with either phenylephrine or pseudoephedrine to relieve sinus congestion and stuffiness.

If a given antihistamine stops being effective in controlling the symptoms, switching to a different antihistamine may restore effectiveness.

IV. These products are available as tablets, caplets, capsules, gelcaps, and as syrups.

Customer Scenario

You are suffering from common seasonal allergies, and it is time to get ONE non-prescription allergy relief product best suited to your need. At the store, and even more so online, you are faced with the dilemma of having to choose this product from among many choices. 

For example, you will find products from major brands such as Alavert, Allegra, Benadryl, Claritin, Xyzal, and Zyrtec.

In addition, you will also find products from many other brand and generic competitors, such as from CVS, Target, Walgreens, and Walmart.

Even when you have narrowed your choice to a single brand, most likely you still must choose from among several options which differ on strength and formulation.

Zyrtec products, for example, are available in many varieties such as:

• Zyrtec Tablets

• Zyrtec Liquid Gels

• Zyrtec Dissolve Tabs

• Zyrtec-D Tablets

Customer Scenario Bottom Line:

The number of choices may be overwhelming. In the absence of key basic information, particularly regarding similarities and differences, it is hard for an average consumer to make the best choice easily.

As done in all my previous posts, the key basic information about OTC allergy medications taken orally is provided in a Frequently Asked Question (FAQs) format and is organized in following sections.

Section I: Product Selection based upon Active Ingredients

Section II: Product Selection based upon Dosing Frequency

Section III: Product Selection based upon Formulation 

Section IV: Selected Brand Name Oral Allergy Products

Section V: Web links to common brand names

Section I: Product Selection based upon Active Ingredients.

Question: 

Looking at the choices of following seven major brand name products:

Alavert    Allegra Benadryl Claritin Equate Xyzal Zyrtec

is there a way to simplify the choice?

Answer:

Indeed, there is way to simplify the choice. Let us look at the following table with some basic information on these brand names:

First thing to note is that the anti-allergy effects of all the products are due to the presence of an antihistamine; in other words, the basic mechanism by which they work is the same for all. They all reduce the symptoms of common allergies by blocking the effect of histamine, a chemical released in tissues in response to an allergen, such as pollen. Most common allergy symptoms are sneezing, itchy watery eyes, itchy nose or throat, and runny/stuffy nose.

Second, even though all contain an antihistamine, these products can be divided into two groups:

Products containing older, sedating antihistamines chlorpheniramine (klor-fen-ir-a-meen) and diphenhydramine (dahy-fen-hy-druh-meen)

and

Products containing newer, non-sedating antihistamines cetirizine (se-tir-a-zeen), levocetirizine (lee-voe-se-tir-a-zeen), loratadine (lor-at-a-deen), and fexofenadine (fex-oh-fen-a-deen).

Question:

Can you please elaborate a bit on sedating and non-sedating antihistamines?

Answer:

Older antihistamines, also labeled as first-generation antihistamines, are classified as sedating because, in addition to having intended anti-allergy effect, they also cause drowsiness as a significant side effect. Newer antihistamines, labeled as second or third generation antihistamines cause little or no drowsiness.

Therefore, if remaining alert is important, products containing newer non-sedating antihistamines would be a better choice. However, if drowsiness is not a concern, for example if taken before bedtime, products containing older sedating antihistamines would be fine.

Note: Diphenhydramine, the sedating antihistamine in Benadryl, is also present as an active ingredient in many OTC-Sleep Aids such as Advil PM, Sominex, and Tylenol PM. Similarly, doxylamine, also a sedating antihistamine, is the active ingredient in Unisom Nighttime Sleep Aid. 

Question:

Even though I take non-sedating antihistamines, why do I still notice some drowsiness?

Answer:

All antihistamines, even those classified as non-sedating, have the potential to produce drowsiness and reduce mental alertness, based upon individual factors. Therefore, it is important for users to know how their body responds to a given antihistamine, sedating or non-sedating. Do not perform tasks requiring alertness unless you know how you react to a given antihistamine.

It is also important to know that the impairment of mental alertness by antihistamines is amplified by the simultaneous use of alcohol, or drugs such the sedatives/hypnotics, narcotics, antidepressants, and tranquilizers.

Question:

I have noticed that my allergy medication doesn’t work as well as it used to. Will switching to a different antihistamine be helpful?

Answer:

There could be many reasons why a given antihistamine doesn’t work as well as it used to. There could be a change in your environment, you may have developed new allergies, or your individual characteristics (example age, other medical conditions) may have changed significantly. Assuming these are not applicable, switching from one antihistamine to another may be worth trying, although scientific research on tolerance to specific antihistamines is sparse.

Question:

For many of the common brand name allergy products listed above, I notice that there are products with names ending in either capital D, example Allegra-D, or names with additional words such as Sinus or Congestion after Allergy, example Benadryl Allergy Plus Congestion.

How these products differ from their regular counterparts?

Answer:

The presence of a capital D at the ending, or addition of the word Congestion or Sinus in the name, denotes the presence of a decongestant, in addition to the antihistamine. The decongestant helps in relieving sinus congestion and stuffiness.

Only two decongestants are approved for use in OTC products: pseudoephedrine  and phenylephrine.

The following table gives you examples of both decongestants.

Note: Please consider the following when trying to decide between pseudoephedrine versus phenylephrine:

1.     When compared side-by-side as decongestants, while pseudoephedrine is more effective than phenylephrine, it also has more side effects, for example on raising the blood pressure. A detailed discussion of this aspect is however well beyond the scope of this post.

2.     Pseudoephedrine containing products require positive identification with a staff member and cannot be bought off-the shelf. Consumers must take the “Product Purchase Card” to a pharmacy staff and provide identification to purchase the product. Phenylephrine containing products, however, have no such restriction and can be bought off-the shelf.

Section II: Product Selection based upon Dosing Frequency

Question:

Regarding frequency of dosing, I see commercials touting the advantage of one product over the others. What do I need to know to make the best decision?

Answer:

Realize that dosing frequency is primarily a matter of convenience. Nevertheless, since dosing frequency can vary from every 4-6 hours to once every 24 hours, it could be an important factor in choosing a product, based upon individual circumstances.

The following table is provided for consumers to easily compare the dosing frequency of various antihistamines.

As can be seen from the table:

• Dosing frequency is highest (every 4-6 hours) for regular chlorpheniramine tablets, and for diphenhydramine products.

• Dosing frequency is intermediate (every 12 hours) for extended-release chlorpheniramine tablets, and for lower strength formulations of cetirizine, loratadine, and fexofenadine.

• Dosing frequency is highest (every 24 hours) for higher strength formulations of cetirizine, loratadine, fexofenadine, and for levocetirizine.

Consumer Tip: In most cases it is easy to know the dosing frequency of a product since it is clearly indicated on the main label. Examples are as follows:

Alavert Allergy 24 HR

Allegra Allergy 12 HR

Children’s Benadryl Allergy 4-6 Hours/Dose

Claritin RediTabs 12 HR

Claritin RediTabs 24 HR

Equate ChlorTabs 4 Hour Relief

Question:

When a product is available in both 12 hours and 24 hours formulations, what should a consumer consider in choosing one over the other?

Answer:

Obviously taking the medication once a day is more convenient. However, taking a 12 hours products does allow one to explore the possibility whether only one dose per day could be sufficient to provide satisfactory relief over a period of 24 hours. Should this be the case, one would achieve satisfactory results with only half the amount of antihistamine per 24 hours period. On the other hand, if this is not the case, one can always repeat the dose after 12 hours, or switch to the 24 hours product.

Section III: Product Selection based upon Formulation

Question:

What basic information do I need to choose between various formulations such as tablets, capsules, gels, and syrups?

Answer: 

If the amount of active ingredient per dose is same, there is no clinically significant difference in overall efficacy among various formulations.

For example,

Claritin® Tablets 24-Hour

Claritin® RediTabs® 24-Hour

Claritin® Liqui-Gels® Capsules 24-Hour

Claritin® Chewables Cool Mint Flavor

All these four different formulations have 10 mg of loratadine, and thus clinically equivalent.

The difference is in how they are taken.

Claritin® Tablets are regular tablets to be swallowed with a liquid.

Claritin® RediTabs® melt-in-your-mouth and thus avoid swallowing

Claritin® Liqui-Gels® Capsules are easier to swallow than tablets

Claritin® Chewables can be chewed while providing cool mint flavor

Therefore, your choice of formulation comes to two factors:

Patient’s limitations/preference in orally taking one formulation over the other; and price.

Of these, patient limitations preferably should be the guiding factor in choosing a formulation. For example, if a patient has difficulty swallowing, melt-in-your-mouth and chewable formulations would be preferable. For children who generally have trouble swallowing solids, liquid preparations would be preferred.

Typically, coated tablets and capsules are easier to swallow because of having smoother surface than corresponding non-coated tablets.

Regarding price, they may differ significantly based upon the formulation. In general, non-coated preparations are least expensive, followed by coated preparations, gels, and liquids in that order. One simple way to compare prices is to look at price per unit/dose. Many retailers such as Walgreens provide such unit price information just below the overall price label.

SECTION IV: Examples of Selected Brand Name Oral Allergy Products

Allegra Allergy 24HR Tablets, 180mg

Allegra Allergy 24HR Gelcaps, 180mg

Allegra Allergy 12HR Tablets, 60mg

Allegra-D Allergy & Congestion 24HR Tablets 180mg + Pseudoephedrine 240mg

Allegra-D Allergy & Congestion 12HR Tablets 60mg + Pseudoephedrine 120mg

Children’s Allegra Allergy 12HR Liquid 30mg/5mL

Children’s Allegra Allergy 12HR Meltable Tablets 30mg

BENADRYL® Allergy ULTRATABS® 25mg

BENADRYL® Allergy Dye-Free LIQUI-GELS® 25mg

BENADRYL® Allergy Plus Congestion ULTRATABS® 25mg + Phenylephrine 10mg

Children’s BENADRYL® Allergy Liquid 12.5mg/5mL

Children’s BENADRYL® Dye-Free Allergy Liquid 12.5mg/5mL

Children’s BENADRYL® Chewables 12.5mg

Children’s BENADRYL® Allergy Plus Congestion, 12.5mg + Phenylephrine 5mg

Claritin® Tablets 24-Hour 10mg

Claritin® Liqui-Gels® Capsules 24-Hour 10 mg

Claritin® Chewables Cool Mint Flavor 10mg

Claritin® RediTabs® 12-Hour 5mg

Claritin® RediTabs® 24-Hour 10mg

Claritin-D® Tablets 12-Hour 5mg + Pseudoephedrine sulfate 120mg

Claritin-D® Tablets 24-Hour 10mg + Pseudoephedrine sulfate 240mg

ZYRTEC® TABLETS 10 mg

ZYRTEC® LIQUID GELS 10 mg

ZYRTEC® DISSOLVE TABS 10 mg

ZYRTEC-D®, 5mg + Pseudoephedrine 120mg

CHILDREN’S ZYRTEC® DISSOLVE TABS 10mg

CHILDREN’S ZYRTEC® ALLERGY SYRUP 5mg/5mL

Xyzal® Allergy 24-Hour

Children’s Xyzal® Allergy 24-Hour

SECTION V: Web links to selected brand names

Question:

Where can I get more information on the products listed above?

Answer: 

Some of the brand name product links are given below:

Disclaimer:

These links are provided to enable consumers to easily get direct information from product manufacturers. Author has no conflict of interest and does not implicitly or explicitly endorse any particular product. While these links were working at the time of posting, future functionality may change.

OTC Oral Anti-allergy Product Links

• Alavert

• Allegra

• Benadryl

• Claritin

• Xyzal

• Zyrtec

Alavert is a Registered Trademark of Foundation Consumer Brands, LLC

Allegra is a Registered Trademark of Chattem, Inc., a Sanofi Company

Benadryl is a Registered Trademark of Johnson & Johnson Consumer Inc.

Claritin is a Registered Trademark of Bayer

Xyzal is a Registered Trademark of Chattem, Inc., a Sanofi Company

Zyrtec is a Registered Trademark of Johnson & Johnson Consumer Inc.