Allegra-D is a combination of two medications: pseudoephedrine (a decongestant) and fexofenadine (an antihistamine). It's taken by people ages 12 years and older to relieve allergy symptoms, like sinus congestion and runny nose. Allegra-D (fexofenadine / pseudoephedrine) is taken by mouth, either every 12 hours or every 24 hours, depending on the formulation (Allegra-D 12-hour or Allegra-D 24-hour. Some common side effects include headache and trouble sleeping. This medication is available as both brand name and generics.
Short-term relief of allergy symptoms in adults and children ages 12 years and older:
Itchy nose or throat
Sneezing
Itchy or watery eyes
Runny or stuffy nose
Sinus congestion or pressure
Allegra-D (fexofenadine / pseudoephedrine) is a combination of two medications that work together to relieve allergy symptoms.
Fexofenadine 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.
Pseudoephedrine is a decongestant. It tightens blood vessels in the nose to relieve sinus pressure.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor as soon as possible if any of the following side effects occur:
More common
Trouble in sleeping
Incidence not known
Difficult or labored breathing
difficulty swallowing
dizziness
fast heartbeat
feeling of warmth
hives or welts
itching skin
itching, puffiness or swelling of the eyelids or around the eyes, face, lips or tongue
large, hive-like swelling on face, eyelids, lips, tongue, throat, hands, legs, feet, sex organs
reddening of the skin, especially around ears
redness of the face, neck, arms and occasionally, upper chest
shortness of breath
skin rash
tightness in chest
swelling of eyes, face, or inside of nose
unusual tiredness or weakness
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Incidence not known
Terrifying dreams causing sleep disturbances
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Starts working within an hour
Easier to take a combination pill instead of two separate pills
Available as a once-daily tablet
Available over the counter (behind the counter)
Tablets can't be crushed or chewed and there isn't a liquid version available
Best to take on empty stomach
Not for children younger than 12 years old
Not a good option for people with kidney or heart problems
Swallow Allegra-D (fexofenadine / pseudoephedrine) tablets whole. Don't cut, crush, or chew the tablets. This will affect the way the medication works since it's made to release the medication into your body slowly over time.
Take Allegra-D (fexofenadine / pseudoephedrine) with a glass of water on an empty stomach. Don't take it with fruit juices because they might affect how well Allegra-D (fexofenadine / pseudoephedrine) gets absorbed into your body.
You might experience trouble sleeping (insomnia) after starting Allegra-D (fexofenadine / pseudoephedrine). To prevent this medication from affecting your sleep, it's best not to take your dose too close to bedtime.
Both fexofenadine and pseudophedrine interact with other medications, such as other cold and allergy medications, or blood pressure medications. Ask your healthcare team or pharmacist to help you check for medication interactions when you're taking Allegra-D (fexofenadine / pseudoephedrine).
Avoid taking Allegra-D (fexofenadine / pseudoephedrine) and antacids containing aluminum or magnesium (e.g., Mylanta, Rolaids) within a few hours of each other. Taking these medications too close together can potentially cause the fexofenadine in Allegra-D to not work as well to treat your allergies.
Stop taking Allegra-D (fexofenadine / pseudoephedrine) and contact your primary care provider if your allergy symptoms don't get better within 7 days of starting Allegra-D (fexofenadine / pseudoephedrine) or if you develop a fever. These might be signs of a serious condition that needs more medical attention.
Store Allegra-D (fexofenadine / pseudoephedrine) 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.
Allegra-D (fexofenadine / pseudoephedrine) 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.
Risk factors: Heart problems | High blood pressure
Pseudoephedrine in Allegra-D can raise your heart rate and blood pressure, even at recommended doses. If you have a history of heart problems or high blood pressure, ask your cardiologist if Allegra-D (fexofenadine / pseudoephedrine) is safe for you before taking this medication. If you get severe headaches, nosebleeds, difficulty breathing, irregular heartbeat, or chest pain while taking Allegra-D (fexofenadine / pseudoephedrine), stop taking it and get medical attention right away. These can be signs of seriously high blood pressure.
Risk factors: Heart problem | High blood pressure | Thyroid problem | High blood sugar (diabetes) | Glaucoma | Breathing problem (e.g., emphysema, long-term bronchitis) | Kidney problems | Urinary condition
Talk with your primary care provider or pharmacist first before you start Allegra-D (fexofenadine / pseudoephedrine) if you have other medical conditions. They can make sure this medication is safe and appropriate for you to take.
People who are 65 years of age or older might feel side effects from Allegra-D (fexofenadine / pseudoephedrine) more intensely. In addition, this medication might worsen certain medical conditions, like high blood pressure, thyroid problems, diabetes, glaucoma, and breathing problems.
Allegra-D contains an antihistamine (fexofenadine) and a decongestant (pseudoephedrine). Antihistamines and decongestants are commonly found in other over-the-counter and prescription medications.
Taking too many antihistamines or too many decongestants can be dangerous and lead to serious side effects, including high blood pressure, seizures, and hallucinations (seeing or hearing things that aren't real).
Ask your primary care provider or pharmacist if you're not sure whether you're taking a medication that has the same or similar ingredients as Allegra-D. Tell your primary care provider or pharmacist about the medications you take or plan to take to make sure they're safe for you. Get medical help or contact a Poison Control Center at 1-800-222-1222 right away if you think you or a loved one accidentally took too much medication.
Allegra-D (fexofenadine / pseudoephedrine) 24-hour tablet:
Each tablet contains 180 mg of fexofenadine and 240 mg of pseudoephedrine.
People ages 12 to under 65 years old: The typical dose is 1 tablet by mouth once a day on an empty stomach. Don't take more than 1 tablet in 24 hours.
People ages 65 years and older: Ask your primary care provider.
Allegra-D (fexofenadine / pseudoephedrine) 12-hour tablet:
Each tablet contains 60 mg of fexofenadine and 120 mg of pseudoephedrine.
People ages 12 to under 65 years old: The typical dose is 1 tablet by mouth every 12 hours on an empty stomach. Don't take more than 2 tablets in 24 hours.
People ages 65 years and older: Ask your primary care provider.
Your dose might be different if you have kidney problems.
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Currently take or have taken an MAOI in the last 14 days
Severe high blood pressure
Severe coronary artery disease
Short-term relief of allergy symptoms in adults and children ages 12 years and older:
Itchy nose or throat
Sneezing
Itchy or watery eyes
Runny or stuffy nose
Sinus congestion or pressure
Runny nose
Itchy nose or throat
Itchy or watery eyes
Stuffy nose
Nasal congestion
Sinus congestion or pressure
Itchy nose or throat
Sneezing
Itchy or watery eyes
Runny or stuffy nose
Sinus congestion or pressure
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Cardinal Health. (2024). Fexofenadine HCl and pseudoephedrine HCl 24 hour- fexofenadine hcl and pseudoephedrine hcl tablet, extended release [package insert]. DailyMed.
CVS Pharmacy. (2024). Fexofenadine hydrochloride and pseudoephedrine hydrochloride tablet, extended release [package insert]. DailyMed.
North, M. L., et al. (2013). Double blind randomized crossover trial of PF-03654764 + fexofenadine in the environmental exposure unit (EEU). Allergy, Asthma & Clinical Immunology.
Sussman, G. L., et al. (1999). The efficacy and safety of fexofenadine HCl and pseudoephedrine, alone and in combination, in seasonal allergic rhinitis. The Journal of Allergy and Clinical Immunology.
U.S. Food and Drug Administration. (2024). Legal requirements for the sale and purchase of drug products containing pseudoephedrine, ephedrine, and phenylpropanolamine.
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