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Allergy relief tablets

By the Life in Good Form editors. Updated 2026-10-15.

We research products from makers' specs and health sources; we do not run hands-on tests. Links to Amazon may earn us a commission at no cost to you. How this works.

The three tablets compared

Details are from each product's DailyMed Drug Facts label. Allegra also comes as a 12 hour tablet with fexofenadine HCl 60 mg, taken with water every 12 hours, with no more than 2 tablets in 24 hours.

What they treat

All three labels list the same uses: they temporarily relieve symptoms due to hay fever or other upper respiratory allergies, including runny nose, sneezing, itchy, watery eyes, and itching of the nose or throat. Each lists its purpose as antihistamine.

None of these single-ingredient tablets lists nasal congestion among its uses. For a stuffy nose from allergies, see our nasal allergy spray guide, which compares steroid sprays that list nasal congestion on their labels. For itchy eyes alone, see our allergy eye drops guide.

Drowsiness

• Zyrtec. The label says drowsiness may occur. Avoid alcoholic drinks; alcohol, sedatives and tranquilizers may increase drowsiness; and be careful when driving a motor vehicle or operating machinery. Ask a doctor or pharmacist before use if you are taking tranquilizers or sedatives.
• Claritin. The label says do not take more than directed, and that taking more than directed may cause drowsiness. The carton is marked non-drowsy when taken as directed.
• Allegra. The label's warnings do not list drowsiness; its main cautions are about juice and antacids.

If you need to drive or work with machinery and have not used Zyrtec before, its label warning is the one to take seriously.

Allegra: juice and antacids

The Allegra label has two rules the others do not:

• Do not take with fruit juices. The directions say to take the tablet with water.
• Do not take at the same time as aluminum or magnesium antacids. If you use an antacid, check its active ingredients; see our antacid chewables guide.

Allegra is also not for children under 12 in tablet form, and adults 65 years and older should ask a doctor before use, the label says.

Who should ask a doctor first

• Liver or kidney disease. Claritin and Zyrtec say ask a doctor before use if you have liver or kidney disease; Allegra says ask if you have kidney disease. Your doctor should determine if you need a different dose.
• Hydroxyzine allergy. Do not use Zyrtec if you have ever had an allergic reaction to an antihistamine containing hydroxyzine.
• Pregnancy and breastfeeding. Zyrtec's label says breastfeeding use is not recommended and to ask a health professional if pregnant. Claritin and Allegra say ask a health professional before use if pregnant or breastfeeding.
• Children under 6. Claritin and Zyrtec tablets say ask a doctor for children under 6. For children's liquid forms, see our guide to antihistamines for kids.

Using them safely

• One antihistamine at a time. Check the active ingredient on every product so you do not double up, especially with combination cold and allergy products.
• Do not take more than directed. All three labels say not to exceed the daily limit.
• Stop for an allergic reaction. Each label says stop use and ask a doctor if an allergic reaction to the product occurs, and seek medical help right away.
• Store properly. Labels say store between 20 and 25 C (68 and 77 F), and Claritin and Allegra say protect from excessive moisture.
• Overdose. Keep out of reach of children; in case of overdose, get medical help or contact a Poison Control Center right away.

Reducing triggers at home helps too; see our mattress protector guide for bedding.

What to look for when you buy

Questions people ask

Which allergy tablet is least likely to make me drowsy?

Zyrtec's label warns drowsiness may occur; Claritin's says only taking more than directed may cause it; Allegra's warnings do not list it.

Can I take Allegra with orange juice?

No. The Allegra label says do not take with fruit juices; take it with water.

Do allergy tablets help a stuffy nose?

These single-ingredient tablets do not list nasal congestion among their uses; steroid nasal sprays do.

Can children take these tablets?

Claritin and Zyrtec tablets are for ages 6 and over; Allegra tablets are for 12 and over.

Can I take two allergy tablets together?

Do not take more than directed, and check active ingredients so you do not double up on antihistamines.

Sources

• Claritin (loratadine) tablet label (dailymed.nlm.nih.gov), DailyMed, U.S. National Library of Medicine
• Zyrtec Allergy (cetirizine HCl) tablet label (dailymed.nlm.nih.gov), DailyMed, U.S. National Library of Medicine
• Allegra Allergy (fexofenadine HCl) tablet label (dailymed.nlm.nih.gov), DailyMed, U.S. National Library of Medicine

Sources checked 2026-10-15.