Popular Over-the-Counter Oral Antihistamine Brands

First-generation antihistamine brands

The oldest group includes first-generation OTC oral antihistamines, including the commonly known diphenhydramine (Benadryl) and chlorpheniramine (Chlor-Trimeton).

They are sedating, which means they’re likely to make you drowsy after you use them. They also don’t last as long in your system, requiring more frequent dosing than the newer generations.

You may commonly see these in night time formulations of cough and cold medications.

Benadryl

Benadryl’s main active ingredient is diphenhydramine, a first-generation antihistamine. It helps relieve runny noses, sneezing, itchy or watery eyes, and nose or throat itching. These symptoms may be due to hay fever, other upper respiratory allergies, or the common cold. Benadryl can also be used to treat hives and reduce redness and itching.

Diphenhydramine comes as a tablet, a rapidly disintegrating (dissolving) tablet, a capsule, a liquid-filled capsule, a dissolving strip, powder, and a liquid to take by mouth.

Other common OTC brands that include diphenhydramine include:

• Banophen
• Siladryl
• Unisom SleepGels
• Benadryl-D Allergy Plus Sinus
• Robitussin Severe Multi-Symptom Cough Cold + Flu Nighttime
• Sudafed PE Day/Night Sinus Congestion

Chlor-Trimeton

Chlorpheniramine is the main active ingredient in Chlor-Trimeton. It helps relieve runny nose, sneezing, itchy or watery eyes, and nose and throat itching from hay fever. It also helps relieve other respiratory allergies.

It comes in immediate-release tablets, extended-release tablets, chewable tablets, lozenges, capsules, and oral liquid formulations.

Other common brands with chlorpheniramine as a main active ingredient include:

• Aller-Chlor
• Alka-Seltzer Plus Cold & Cough Liquid Gels
• Allerest Maximum Strength
• Comtrex

Side effects of first-generation antihistamines

Some of the more common side effects of first-generation antihistamines can include:

• drowsiness
• dry mouth, nose, and throat
• headache

Some side effects that are not as common include:

• dizziness
• nausea
• vomiting
• loss of appetite
• constipation
• chest congestion
• muscle weakness
• hyperactivity, especially in children
• nervousness

Some serious side effects can include:

• vision problems
• trouble urinating or pain with urinating

All of these side effects are more common in older people.

Warnings

If you have an enlarged prostate that makes it difficult for you to urinate, you should talk with your doctor before using first-generation antihistamines. These drugs can make your urination problem worse. You should also talk with your doctor before using these drugs if you have any of these health concerns:

• trouble breathing from emphysema or chronic bronchitis
• glaucoma
• high blood pressure
• heart disease
• seizures
• thyroid problems

If you take other drugs that can make you drowsy, such as sedatives or tranquilizers, talk with your doctor before using first-generation antihistamines. You should also avoid drinking alcohol with any antihistamine because it can increase the side effects of drowsiness.

Second- and third-generation antihistamine brands

Second-generation and third-generation antihistamines are typically grouped together and referred to as “newer antihistamines.”

These OTC oral antihistamines were developed to target their action on more specific receptors. This helps decrease side effects, including drowsiness. Also, these drugs work longer in your body, so you need fewer doses.

Note that medications effect each person differently. You may experience better symptom relief from a certain antihistamine compared to another. On the other hand, you may also experience more side effects, like sleepiness, with certain antihistamines more than others.

Zyrtec

Cetirizine is the main active ingredient in Zyrtec. It helps relieve runny nose, sneezing, itchy and watery eyes, and nose or throat itching from hay fever and other upper respiratory allergies. Zyrtec can also help relieve redness and itching caused by hives.

It comes in a chewable tablet, a tablet that dissolves in your mouth, a liquid-filled capsule, and a syrup.

Other common OTC brands with cetirizine as the main active ingredient include:

• Aller-Tec
• Alleroff
• Zyrtec-D
• Wal Zyr-D
• Cetiri-D

Side effects

Some common side effects of Zyrtec can include:

• drowsiness
• headache
• stomach pain

Serious side effects can include trouble breathing or swallowing.

Warnings

• Talk with your doctor about whether you should use the bronchodilator or theophylline. Zyrtec can interact with this drug and increase your risk of side effects.
• Avoid taking Zyrtec with alcohol. Although cetirizine causes less drowsiness than a first-generation antihistamine, it can still make you drowsy. Drinking alcohol while you take it can increase this drowsiness.
• Talk with your doctor before using Zyrtec if you have liver or kidney disease. Liver and kidney disease can affect how your body processes and removes cetirizine.
• If you have asthma, you should also talk with your doctor before using Zyrtec. In rare cases, cetirizine has been shown to cause bronchospasms.

Claritin

Loratadine is the main active ingredient in Claritin. It helps relieve runny nose, sneezing, itchy, watery eyes, and itching of the nose or throat due to hay fever and other upper respiratory allergies. Claritin can also be used to treat hives. It comes in a tablet that dissolves in your mouth, a chewable tablet, a liquid-filled capsule, and a syrup.

Loratadine is also the main active ingredient in these other OTC brands:

• Claritin-D
• Alavert
• Alavert-D
• Wal-itin

Side effects

Some of the common side effects of Claritin include:

• headache
• drowsiness

Serious side effects of Claritin can include allergic reactions. Symptoms can include:

• rash
• itching
• trouble breathing or swallowing
• swelling of your face, throat, tongue, lips, eyes
• hoarseness

Warnings

• Talk with your doctor before using Claritin if you have liver or kidney disease. Liver and kidney disease can affect how your body processes and removes loratadine, causing more of the drug to stay in your body and increasing your risk of side effects.
• You should also talk with your doctor before using Claritin if you have asthma. In rare cases, loratadine has been shown to cause bronchospasms.

Allegra

Fexofenadine is the main active ingredient in Allegra. It helps relieve runny nose, sneezing, itchy and watery eyes, and itching of the nose or throat due to hay fever or other upper respiratory allergies. Allegra can also be used to treat hives and skin rash. It comes in a tablet, a tablet that dissolves in your mouth, a gel-coated capsule, and a liquid.

Side effects

Some of the common side effects of Allegra can include:

• headache
• dizziness
• diarrhea
• vomiting
• pain in your arms, legs, or back
• pain during menstrual periods
• cough
• upset stomach

Serious side effects of Allegra can include allergic reactions. Symptoms include:

• hives
• rash
• itching
• trouble breathing or swallowing
• swelling of your face, throat, tongue, lips, eyes

Warnings

• Talk with your doctor before you use Allegra if you take the antifungal ketoconazole, the antibiotics erythromycin or rifampin, or any antacids. These drugs can all interact with Allegra to either increase your risk of side effects or decrease its effectiveness.
• Avoid drinking fruit juice while taking Allegra. Fruit juice can also decrease the amount of Allegra that your body absorbs, making the drug less effective.
• If you have kidney disease, talk with your doctor before using Allegra. Kidney disease interferes with your body’s removal of Allegra. This can lead to an increased risk of side effects.

Frequently asked questions

Is Benadryl or Zyrtec a better antihistamine?

Which brand of antihistamine is best for you will depend on exactly what you need to treat and your doctor’s recommendation. Generally, you take Zyrtec once a day for longer-lasting relief, whereas you must take Benadryl every 4 to 6 hours. However, Zyrtec tends to have fewer side effects, whereas Benadryl can make you more drowsy than Zyrtec. That said, the effect of these drugs may vary from person to person.

Which is better, Claritin or Zyrtec?

Like Zyrtec, Claritin only needs to be taken once a day. However, unlike Zyrtec, Claritin is less likely to make you sleepy. Ask your doctor which of these is best for you. It may come down to trying out both and seeing which works best while making you the least drowsy.

Things to consider when choosing an antihistamine

If you’re unsure which medication might be best for you, talk with your doctor or pharmacist. If you take other medications to treat allergy symptoms, ensure that the active ingredients are not the same or in the same drug class as the active ingredient in the antihistamine you want.

You don’t want to take too much of any particular drug. To help prevent this, always check with your doctor or pharmacist.

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