Fexofenadine (Allegra) is an antihistamine. It's used to ease symptoms of allergy and hives in adults and children. Fexofenadine (Allegra) can be found over the counter as a tablet, fast-melting tablet, and liquid. This medication is taken once or twice per day, depending on the formulation. Fexofenadine (Allegra) starts to work in about 2 hours and its effects can last up to 24 hours. Fexofenadine (Allegra) doesn't make you as drowsy compared to some other antihistamines, such as diphenhydramine (Benadryl). Other possible side effects of fexofenadine (Allegra) include headache and dry mouth.
Short-term relief of allergy symptoms (sneezing, runny nose, itchy or watery eyes, itchy nose or throat)
Fexofenadine (Allegra) is a second-generation antihistamine. It blocks histamine, a natural chemical in your body that can cause allergy symptoms like itchiness, itchy eyes, or runny nose. By blocking histamine, fexofenadine (Allegra) helps relieve allergy symptoms.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report to your care team if they continue or are bothersome):
First-choice option for relieving allergy symptoms
Some products can also be used to relieve itchiness from hives.
Available as 12-hour and 24-hour tablets, as well as a liquid and quick-dissolving tablets for those who have a hard time swallowing pills
All formulations available over the counter
Liquid form might not be the best choice for people on a low-salt diet because it contains sodium
Once-daily formulations not recommended for children younger than 12 years old
Might have a higher risk of side effects if you have liver or kidney problems
Can cause headache
Fexofenadine (Allegra) can be taken only when you have allergy symptoms every once in a while. But if you have allergy symptoms on a daily basis, taking it regularly according to the manufacturer's directions can give you the most relief.
Take fexofenadine (Allegra) with water only. Don't take it with fruit juices because they can affect how well fexofenadine (Allegra) gets absorbed into your body.
If you're pregnant, discuss with your healthcare provider about the risks and benefits of taking fexofenadine (Allegra) before using. It's not completely clear if fexofenadine (Allegra) is safe to take during pregnancy, but studies suggest that the medication doesn't appear to raise the risk of harm in unborn babies when used during pregnancy.
Talk to your provider about the risks and benefits of taking fexofenadine (Allegra) while breastfeeding. There's little information about fexofenadine (Allegra) use while breastfeeding and the effects it has on breast milk or nursing infants.
For the liquid form: Use a medication dose cup or an oral syringe to measure your dose of fexofenadine (Allegra). Ask your pharmacist to provide you with one if the product doesn't include it in its packaging or if you need extras. Don't use household spoons because they might not be accurate and might cause you to take the wrong dose.
For the orally disintegrating tablet: Place the tablet on your tongue, and let it dissolve in your mouth. You can take it with or without water.
Don't use other antihistamines while taking fexofenadine (Allegra) without talking to your HCP or pharmacist first. Doing so can raise your risk of taking too much medication (overdose). This can lead to severe side effects, including seizures, hallucinations (seeing things that aren't real), and even death.
Avoid taking fexofenadine (Allegra) and antacids containing aluminum or magnesium (e.g., Mylanta, Rolaids) within 15 minutes of each other. Taking these products too close to the allergy medication can affect how well fexofenadine (Allegra) gets absorbed into your body. This can potentially make fexofenadine (Allegra) not work as well to treat your allergies.
Store fexofenadine (Allegra) up and away from children and pets. That way, they're less likely to reach it and accidentally take the medication. If you think your child accidentally took the medication, call a Poison Control Center right away at 1-800-222-1222.
For relieving itchiness from hives
Some formulations of fexofenadine (Allegra) can be used to help relieve itchiness from hives. But if you have hives that happen with any trouble breathing, speaking, or swallowing; dizziness; swelling in or around your mouth; or drooling; get emergency help right away. These can be signs of a severe allergy or anaphylaxis, which can be life-threatening if not treated immediately.
Stop using fexofenadine (Allegra) to relieve hives and contact a provider if your symptoms don't get better after 3 days of taking the medication or if your hives last more than 6 weeks. There might be a better treatment for you.
Fexofenadine (Allegra) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Fexofenadine (Allegra) and other antihistamines can be found in many over-the-counter products. Taking too much fexofenadine (Allegra) or using more than one medication containing an antihistamine (including products used on the skin) can lead to an accidental overdose. This can cause serious side effects, such as seizures, hallucinations, or even death.
To prevent an accidental overdose, read package labels carefully. If you're not sure if a product has an antihistamine, ask your pharmacist. Don't start any new medications while taking fexofenadine (Allegra) without talking to your HCP or pharmacist first. If you think you or your loved one has taken too much medication, get medical help right away or contact a Poison Control Center at 1-800-222-1222.
The fexofenadine (Allegra) orally disintegrating tablets contain phenylalanine, a component of the artificial sweetener aspartame. If you have a genetic condition called phenylketonuria (PKU), taking this form of the medication can be dangerous for you. Read the manufacturer's label on the fexofenadine (Allegra) product you have to see if there's a warning for people with PKU. Ask your pharmacist if you're not sure if a particular fexofenadine (Allegra) is safe for you. There are other formulations of the medication that might be safer for you.
Different formulations of fexofenadine (Allegra) have different dosing directions and age-cut offs. Make sure to follow the instructions on the manufacturer's label for specific directions for your product. Some examples include:
Age 65 years and older: Ask your healthcare professional (HCP).
Age 12 to under 65 years: The typical dose is 1 tablet (60 mg) by mouth every 12 hours. Don't take more than 2 tablets within a 24-hour period.
Age younger than 12 years: Ask your child's pediatrician.
Age 65 years and older: Ask your HCP.
Age 12 to under 65 years: The typical dose is 1 tablet (180 mg) by mouth once per day. Don't take more than 1 tablet within a 24-hour period.
Age younger than 12 years: Ask your child's pediatrician.
Fexofenadine oral suspension: Each 5 mL contains 30 mg of fexofenadine.
Age 65 years and older: Ask your HCP.
Age 12 to under 65 years: The typical dose is 10 mL by mouth every 12 hours. Don't take more than 20 mL within a 24-hour period.
Age 2 to up to 12 years of age: The typical dose is 5 mL by mouth every 12 hours. Don't take more than 10 mL within a 24-hour period.
Age younger than 2 years: Ask your child's pediatrician.
Fexofenadine orally disintegrating tablet
Age 65 years and older: Ask your HCP.
Age 12 to under 65 years: The typical dose is 2 tablets (60 mg total) dissolved on the tongue every 12 hours on an empty stomach. Don't take more than 4 tablets within a 24-hour period.
Age 6 to under 12 years: The typical dose is 1 tablet (30 mg total) dissolved on the tongue every 12 hours on an empty stomach. Don't take more than 2 tablets within a 24-hour period.
Age younger than 6 years: Ask your child's pediatrician.
Short-term relief of allergy symptoms (sneezing, runny nose, itchy or watery eyes, itchy nose or throat)
Short-term relief of allergy symptoms (runny nose, itchy nose, itchy or watery eyes)
Short-term relief of allergy symptoms (sneezing, runny nose, itchy or watery eyes, itching of the nose or throat)
Relief of itchiness due to chronic (long-term) hives in children ages 6 months to under 6 years old - certain liquid solutions only
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