What Is Allegra?
Allegra is the brand name for fexofenadine hydrochloride, a second-generation antihistamine used to treat seasonal allergy symptoms like sneezing, runny nose, itchy eyes, and hives. It blocks histamine without causing significant drowsiness, unlike older antihistamines such as Benadryl.[1]
How Does Allegra Work?
Fexofenadine prevents histamine from binding to H1 receptors in the body, reducing allergic reactions. It doesn't cross the blood-brain barrier easily, minimizing sedation. Effects start within 1 hour and last up to 24 hours.[1][2]
Common Doses and Forms
- Adults and children 12+: 180 mg tablet or 60 mg twice daily for allergies; 180 mg once daily for hives.
- Children 6-11: 30 mg twice daily.
Available as tablets, orally disintegrating tablets, oral suspension, and gelcaps. Over-the-counter in most places since 2001.[1]
Who Makes Allegra?
Sanofi markets Allegra in the US under license from original developer Hoechst Marion Roussel (now part of Sanofi). Generic versions come from Teva, Perrigo, and others.[1][3]
Side Effects Patients Report
Most common: headache, drowsiness (rare, <2%), nausea. Serious risks include allergic reactions or worsened asthma. Avoid with fruit juices like grapefruit, which reduce absorption by 30%. Safe for most, but consult a doctor if pregnant or on other meds.[1][2]
How Allegra Compares to Zyrtec or Claritin
| Feature | Allegra | Zyrtec (cetirizine) | Claritin (loratadine) |
|---------|---------|----------------------|-----------------------|
| Drowsiness risk | Lowest | Moderate | Lowest |
| Onset time | 1 hour | 1 hour | 1-3 hours |
| Duration | 24 hours | 24 hours | 24 hours |
| Best for | Hives, fast relief | Severe symptoms | Mild allergies |
Allegra edges out for non-drowsy hives treatment; Zyrtec acts faster on intense itching.[2]
When Does the Allegra Patent Expire?
Core patents on fexofenadine expired in 2003 in Europe and 2004 in the US, enabling generics. No active US patents block OTC generics per DrugPatentWatch.[4] Some formulation patents lingered until 2010s but didn't halt market entry.
Generic Availability and Pricing
Generics match brand efficacy at lower cost—$10-20 for 30 tablets vs. $30+ for Allegra-D (with pseudoephedrine). Store brands like Equate are identical. Check GoodRx for deals.[3]
Can You Take Allegra with Other Allergy Meds?
Yes with nasal sprays like Flonase, but skip with other oral antihistamines to avoid overlap. Pairing with decongestants needs caution for blood pressure.[1]
[1] FDA Label: https://www.accessdata.fda.gov/drugsatfda_docs/label/2018/020655s058lbl.pdf
[2] Mayo Clinic: https://www.mayoclinic.org/drugs-supplements/fexofenadine-oral-route/description/drg-20067082
[3] Drugs.com: https://www.drugs.com/allegra.html
[4] DrugPatentWatch.com: https://www.drugpatentwatch.com/p/tradename/ALLEGRA