Allegra vs Allegra D

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For individuals suffering from allergies, certain medications can help in managing symptoms such as runny nose, itching, and sneezing. Allegra and Allegra-D are two such drugs that offer relief from these discomforts. Both contain the active ingredient fexofenadine which is an antihistamine that works by blocking histamines, substances in the body responsible for allergy symptoms. However, there's a distinctive difference between them: Allegra-D also contains pseudoephedrine, a decongestant that relieves sinus congestion and pressure. Therefore while both effectively treat allergies, only Allegra-D deals with nasal congestion related to sinusitis or seasonal allergies due to its additional component.

What is Allegra?

Fexofenadine (the generic name for Allegra) is a second-generation antihistamine designed to treat symptoms of seasonal allergies such as sneezing, runny nose, itchy or watery eyes, and itching of the nose or throat. Unlike first-generation antihistamines, Fexofenadine does not readily enter the brain from the blood; hence it causes less drowsiness. It was approved by the FDA in 1996.

Allegra-D has an added decongestant component called pseudoephedrine, which aids in relieving sinus pressure and nasal congestion associated with allergies. While Allegra primarily works on histamine receptors to reduce allergic reactions without causing sedation, Allegra-D's additional influence on alpha-adrenergic receptors results in narrowing of blood vessels within the nasal passage— thus improving breathing difficulties associated with congestion.

However, this extra effect could lead to increased side effects like insomnia or nervousness compared to standard Allegra. Therefore one should consider their specific symptoms and potential side-effect tolerances when deciding between these two medications.

What conditions is Allegra approved to treat?

Allegra and Allegra D are both approved for the treatment of different allergy-related conditions:

  • Seasonal Allergic Rhinitis (SAR), also known as hay fever
  • Chronic Idiopathic Urticaria (CIU), commonly referred to as hives

In addition, Allegra D is also indicated for the relief of nasal congestion due to the common cold or associated with seasonal allergic rhinitis, thanks to its added decongestant component.

How does Allegra help with these illnesses?

Allegra, also known as fexofenadine, helps manage allergy symptoms by blocking the effects of histamine in your body. Histamine is a compound that's released by cells in response to injury and allergic or inflammatory reactions, resulting in contraction of smooth muscle and dilation of capillaries. It does this by attaching to receptors on cells found in the nose and throat, causing them to swell and leak fluid which leads to itching, sneezing, runny nose or watery eyes.

On the other hand, Allegra-D contains an additional component called pseudoephedrine - a decongestant that shrinks blood vessels in the nasal passages. This helps reduce stuffiness and sinus pressure often associated with allergies. Therefore while both Allegra (fexofenadine) can help patients manage their allergic reactions; if you are dealing with nasal congestion on top of itchy/watery eyes or runny noses then Allegra-D would be a better option as it includes an extra ingredient specifically designed for such symptom relief.

What is Allegra D?

Allegra-D is a brand name for the combination of fexofenadine and pseudoephedrine, which are both used to treat allergy symptoms. Fexofenadine, an antihistamine, works by reducing the effects of histamines in your body that can cause itching, sneezing, runny nose, and watery eyes. Pseudoephedrine is a decongestant that decreases swelling (inflammation) in the nasal passages to make breathing easier. This combination was first approved by the FDA in 1997.

As Allegra-D contains pseudoephedrine alongside fexofenadine it not only tackles allergic reactions but also helps relieve congestion associated with these reactions or common colds. However this addition means it may have different side-effects than regular Allegra; including nervousness or restlessness as common side effects due to its stimulant nature compared to normal Allegra's more sedative effect.

What conditions is Allegra D approved to treat?

Allegra D stands out from its counterpart, Allegra, with an additional active ingredient designed to alleviate a specific set of symptoms. The FDA has approved Allegra D for the treatment of:

  • Seasonal Allergic Rhinitis (SAR), which is more commonly known as hay fever.
  • Nasal congestion and sinus pressure associated with both SAR and perennial allergic rhinitis (PAR).

How does Allegra D help with these illnesses?

Pseudoephedrine is a decongestant that shrinks blood vessels in the nasal passages, and it plays a significant role in reducing congestion symptoms. Allegra D combines both fexofenadine (the active ingredient of standard Allegra) which helps to alleviate allergy symptoms, and pseudoephedrine. This makes it highly effective for those suffering from additional discomfort caused by sinus pressure or stuffy nose along with allergies. The combination works synergistically to relieve congestion as well as common allergic reactions like sneezing, itching eyes/nose/throat, runny nose and watery eyes. Therefore, while Allegra alone can be quite beneficial for treating typical allergy symptoms, Allegra D goes a step further by addressing nasal and sinus congestion too.

How effective are both Allegra and Allegra D?

Both fexofenadine (Allegra) and pseudoephedrine-fexofenadine combination (Allegra D) have been approved by the FDA for over two decades, with Allegra gaining approval in 1996 and Allegra D following shortly after in 1997. Both work to effectively alleviate symptoms of seasonal allergies, but they act on different receptors within the body. Fexofenadine is an antihistamine that targets histamine H1 receptor sites to reduce allergic responses while pseudoephedrine works as a decongestant by constricting blood vessels within nasal passages.

A direct comparison of fexofenadine alone versus its combination with pseudoephedrine revealed similar effectiveness in reducing allergy symptoms overall. However, those taking the combined treatment reported better relief from nasal congestion than those using fexofenadine alone due to the added decongestant effect of pseudoephedrine.

A meta-analysis studying various antihistamines showed that fexofenadine was effective at reducing allergy symptoms and had fewer side effects compared to many other drugs in its class. It was also well-tolerated among a variety of populations including children and older adults, making it one of the most prescribed antihistamines worldwide.

The addition of pseudoephedrine adds another layer to treating allergy symptoms - particularly nasal congestion - which may not be fully addressed by an antihistamine alone. However, this benefit comes with additional considerations such as potential interference with sleep or increased heart rate due to its stimulant properties. Thus, Allegra D is usually recommended for daytime use only or for individuals whose primary symptom is severe congestion.

abstract image of a researcher studying a bottle of drug.

At what dose is Allegra typically prescribed?

Oral dosages of Allegra (fexofenadine) for adults and children over 12 years range from 60 mg twice daily or 180 mg once daily. Children aged 6-11: should be given a dosage of 30mg twice daily. In comparison, Allegra D which contains an additional decongestant (pseudoephedrine), is typically taken as one tablet (60 mg fexofenadine/120 mg pseudoephedrine) every twelve hours or one tablet (180mg fexofenadine/240mg pseudoephedrine) every twenty-four hours. It's important to avoid exceeding the recommended dose in all instances without consulting your healthcare provider, due to potential risks associated with excessive intake of pseudoephedrine.

At what dose is Allegra D typically prescribed?

Allegra D treatment typically begins with a dosage of 60 mg (containing 60 mg fexofenadine and 120 mg pseudoephedrine) every 12 hours, taken by mouth on an empty stomach. It's crucial not to take more than two doses in any given day. If the symptoms persist or worsen after several days, your doctor may choose to increase the dose to as much as one Allegra D 24-hour pill (consisting of 180mg fexofenadine and 240mg pseudoephedrine) once per day. This should only be done under a healthcare provider's supervision, due to potential increases in side effects such as insomnia or heart palpitations associated with the higher levels of pseudoephedrine contained in Allegra D compared to regular Allegra.

What are the most common side effects for Allegra?

Common side effects of Allegra include:

  • Cough,
  • Fever,
  • Painful menstruation
  • Headache

Whereas the common side effects of Allegra-D include not only all the above but also:

  • Nervousness
  • Dizziness or lightheadedness
  • Restlessness or excitability (especially in children)
  • Insomnia,
  • Dry mouth or throat, -Increased heart rate.

It is important to note that both drugs are used for relief from allergy symptoms but they are different due to an additional component in Allegra-D which is pseudoephedrine. This substance helps with congestion and can cause some of these additional side effects.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Allegra?

While both Allegra and Allegra D are antihistamines that effectively treat allergy symptoms, they have different side effects due to the presence of an additional decongestant in Allegra D. Here are some rare but severe potential side effects you should be aware of:

  • Signs of allergic reaction: Hives, difficulty breathing, swelling in your face or throat.
  • Severe dizziness or nervousness
  • Difficulty sleeping or restlessness (more common with Allegra-D because it contains pseudoephedrine)
  • Fast or irregular heartbeats, palpitations
  • Blurred vision
  • Symptoms indicative of urinary tract issues like pain while urinating, inability to pass urine - this could happen more frequently with the use of Allegra D.

If you experience any such symptoms when taking either medication type, seek immediate medical attention. As always before starting any new drug regimen make sure you discuss all possible risks and benefits with a healthcare professional.

What are the most common side effects for Allegra D?

While both Allegra and Allegra D can relieve allergy symptoms, the D version contains an additional decongestant to relieve sinus pressure and congestion. With this added component in Allegra D, it may cause certain side effects such as:

  • Dry mouth or throat
  • Headache, dizziness
  • Tension or nervousness
  • Difficulty sleeping (insomnia)
  • Increased heart rate
  • Mild tremors
  • Stomach discomfort including nausea, loss of appetite or constipation.

However, these are common side effects that should subside as your body adjusts to the medication. If they persist or worsen over time, consult your healthcare provider immediately.

Are there any potential serious side effects for Allegra D?

While Allegra is a safe medication for most people, its decongestant version, Allegra D, can have more severe side effects. In rare cases, it can cause:

  • Signs of an allergic reaction: difficulty breathing; hives; swelling of your face, lips, tongue or throat
  • Heart disease symptoms: chest pain or pressure; rapid heartbeats; feeling light-headed
  • High blood pressure signs: severe headache; blurred vision; pounding in your neck or ears
  • Symptoms of circulation problems - such as leg cramps and numbness/weakness accompanied by pale skin coloration.

If you experience any of these symptoms while taking Allegra D, seek emergency medical help immediately. It's also noteworthy to mention that this medication may lead to sleep issues due to the stimulant qualities found in pseudoephedrine.

Contraindications for Allegra and Allegra D?

Both Allegra and Allegra-D are used to alleviate symptoms of allergies, such as runny nose, sneezing, itchy or watery eyes. If you notice your allergic reactions worsening after taking either medication, please seek immediate medical attention.

Neither Allegra nor Allegra-D should be taken if you have kidney disease unless advised by a physician. Always inform your doctor about any medications that you're currently using; this includes over-the-counter drugs and herbal supplements as well.

Allegra-D contains an additional component known as pseudoephedrine which is a decongestant. This helps in relieving stuffy nose symptoms but could also cause insomnia or other sleep disturbances. Therefore, avoid taking it close to bedtime.

It's important to note that consuming fruit juice can decrease the effectiveness of these medications so try to avoid drinking fruit juice around the time you take Allegra or Allegra D.

Lastly, unlike regular Allegra (fexofenadine), due to its pseudoephedrine content, there may be certain restrictions on buying and selling of products containing this substance like Allgera-D because people might use pseudoephedrine illegally.

How much do Allegra and Allegra D cost?

For the brand name versions of these drugs:

  • The price of 30 tablets of Allegra (180 mg) averages around $20, which works out to approximately $0.67/day.
  • The price of 24 tablets of Allegra-D (60mg/120mg) is about $26, working out to roughly $1.08/day.

Thus, if you need a decongestant along with an antihistamine (which is what Allegra-D provides), it would be more costly on a per-day treatment basis compared to regular Allegra. Please note that cost should not be the primary consideration in determining which drug is right for you; effectiveness and side effects are also critical factors.

In terms of generic versions:

  • Fexofenadine Hydrochloride (generic version for Allegra) costs between $10 and $15 for 30 x 180 mg tablets, or from as low as $.33 up to $.50 per day.
  • Fexofenadine-Pseudoephedrine Extended Release Tablets (generic version for Allegra-D) can range from around $16 -22 for 15 x 60mg/120mg tablets, translating into approx $.53 –$1.46 per day depending on dosage frequency.

Popularity of Allegra and Allegra D

Fexofenadine, commonly known by the brand name Allegra, is an effective antihistamine used for treating seasonal allergy symptoms and chronic hives. In 2020, approximately 6 million prescriptions were filled in the US for fexofenadine (Allegra), accounting for nearly 15% of all second-generation antihistamine prescriptions.

On the other hand, Allegra-D combines fexofenadine with pseudoephedrine - a decongestant that relieves stuffy nose and sinus pressure. Its usage is more targeted towards individuals who suffer from nasal congestion along with their allergies. Although exact prescription numbers are harder to ascertain due to its over-the-counter status and combination formulation, it's estimated that Allegra-D accounted for about 8% of total market share among combined antihistamine-decongestants in the same year.

Overall, both versions have maintained steady prevalence over recent years due to their effectiveness in managing allergy symptoms without causing significant drowsiness – a common side effect observed with first-generation antihistamines.


Both Allegra (fexofenadine) and Allegra D are well-established treatments for allergies, backed by numerous clinical studies indicating their effectiveness in relieving symptoms such as sneezing, runny nose, watery eyes, and itching of the nose or throat. Both drugs contain fexofenadine as an active ingredient; however, Allegra D also includes pseudoephedrine which is a decongestant that relieves stuffy nose and ear congestion symptoms.

Given these differences in composition and mechanism of action—with fexofenadine acting primarily on histamines to reduce allergic reactions while pseudoephedrine works mainly on blood vessels to decrease swelling—these medications may be chosen under different circumstances. For example, if one has allergy-related nasal congestion along with other typical allergy symptoms, then using Allegra D could provide broader symptom relief.

While both forms of this medication exist in generic form offering significant cost savings especially for those paying out-of-pocket, it's crucial to note that due to the presence of pseudoephedrine—a substance commonly misused in making methamphetamine—Allegra D is regulated more strictly than regular Allegra and kept behind the pharmacy counter.

The side effect profile between these two versions does differ somewhat: while both are generally well-tolerated they can cause headaches or drowsiness. However, due to the decongestant component of Allegra-D there might be additional side effects like nervousness or restlessness. It's important for patients starting any treatment regimen involving these drugs to closely monitor their responses and speak with a healthcare professional immediately should they experience any adverse effects.