Zyrtec vs Allegra

Overview

Zyrtec Overview

Zyrtec Details

Allegra Overview

Allegra Details

Comparative Analysis

Zyrtec Prescription Information

Allegra Prescription Information

Zyrtec Side Effects

Allegra Side Effects

Safety Information

Cost Analysis

Market Analysis

Summary

Introduction

For patients suffering from ongoing allergies, certain antihistamines can alleviate symptoms such as runny nose, sneezing, itchy or watery eyes. Zyrtec and Allegra are two such drugs that are commonly used to manage these allergy symptoms. They each work by blocking the action of histamine in your body which is a substance responsible for allergic reactions. Zyrtec (cetirizine) has a higher tendency to cause drowsiness compared to Allegra (fexofenadine), making it potentially more useful at night or when you don't need to be alert. On the other hand, Allegra tends not to cause drowsiness and may be better suited for use during daytime hours when alertness is necessary.

What is Zyrtec?

Cetirizine (the generic name for Zyrtec) was a significant advancement in the second generation of antihistamines, which were developed to provide relief from allergy symptoms with fewer side effects compared to first-generation antihistamines. Cetirizine was approved by the FDA in 1995. It works by blocking histamine, a substance your body makes during an allergic reaction, thereby reducing or preventing the typical symptoms of allergies such as itching, sneezing, runny nose and watery eyes. Zyrtec has a stronger effect on histamine receptors than some other antihistamines without significantly affecting other receptors in the body that can lead to unwanted side effects.

Fexofenadine (the generic name for Allegra), another second-generation antihistamine introduced later, provides similar benefits but may be less likely than cetirizine to cause drowsiness - a common downfall with many allergy medications. Both drugs are available over-the-counter and offer once-daily dosing that covers all day and night symptom relief.

What conditions is Zyrtec approved to treat?

Zyrtec is approved for the treatment of various allergy-related conditions:

  • Seasonal allergic rhinitis, also known as hay fever
  • Chronic urticaria, commonly referred to as hives
  • Perennial allergic rhinitis, an all-year-round allergy condition
  • Allergies that cause itchy or watery eyes or an itchy throat

How does Zyrtec help with these illnesses?

Zyrtec, also known as cetirizine, helps to manage allergic reactions by blocking the action of histamine in the body. It does this by attaching itself to histamine receptors on cells, preventing histamine from triggering an allergic response. Histamine is a compound that plays a crucial role in many bodily functions such as immune responses and regulation of gut function; it also acts as a neurotransmitter for our brains. In allergies, however, excessive release of histamines can lead to symptoms like runny nose, sneezing and itching. By inhibiting the action of histamines with Zyrtec, these allergy symptoms can be effectively alleviated.

On the other hand, Allegra (fexofenadine) works similarly but has different properties which may make it more appropriate for certain individuals or situations. Like Zyrtec it blocks the action of histamine at H1 receptor sites throughout your body thus reducing allergy symptoms. However compared to Zyrtec it's less likely to cause drowsiness because it doesn't cross into brain tissues from blood as easily.

What is Allegra?

Allegra, the brand name for fexofenadine, is an antihistamine that blocks a substance in the body called histamine. This action helps reduce symptoms of allergic reactions such as runny nose, watery eyes, itching or hives. Fexofenadine was first approved by the FDA in 1995 and has since become available over-the-counter. Unlike some other antihistamines like Zyrtec (cetirizine), Allegra does not cross into the brain from the blood and therefore does not cause drowsiness when taken at recommended doses. In fact, it's known to be non-sedating which makes it ideal for people who need to remain alert during their day-to-day activities. The side effect profile of Allegra also differs from Zyrtec; although both can cause headaches and dry mouth, only Zyrtec may potentially cause sedation or fatigue due to its different mechanism of action.

What conditions is Allegra approved to treat?

Allegra is a non-drowsy antihistamine that's FDA approved for the treatment of:

  • Seasonal allergic rhinitis, also known as hay fever
  • Chronic idiopathic urticaria, which are hives with no known cause. It helps provide relief from these conditions without causing drowsiness, making it a suitable option for individuals who require medication but still need to stay alert and focused throughout their day.

How does Allegra help with these illnesses?

Histamine is a compound which is released by cells in response to injury and allergic or inflammatory reactions, causing contraction of smooth muscle and dilation of capillaries. Allegra, also known as fexofenadine, works effectively against the actions of histamine in the body. It accomplishes this by blocking one type of receptor for histamine (the H1 receptor) and thus prevents activation of H1 receptor-containing cells by histamine. This helps alleviate symptoms like watery eyes, runny nose, itching eyes/nose, sneezing, hives, and itching. Unlike first-generation antihistamines such as Zyrtec (cetirizine), Allegra does not cross the blood-brain barrier significantly and therefore causes less drowsiness than many other antihistamines. It's often prescribed when patients want relief from their allergy symptoms without feeling sedated.

How effective are both Zyrtec and Allegra?

Both cetirizine (Zyrtec) and fexofenadine (Allegra) are widely used as over-the-counter treatments for allergy symptoms such as sneezing, runny nose, itchy or watery eyes, hives, and itching. These medications were approved by the FDA in 1996 and 2000 respectively. While both drugs counteract allergic reactions by blocking histamine receptors in the body, they do so with slightly different mechanisms.

A direct comparison of cetirizine and fexofenadine was conducted in a double-blind clinical trial in 2001; both antihistamines showed similar efficacy in controlling symptoms of seasonal allergic rhinitis but cetirizine's effects lasted longer into the 24-hour dosing period. The study also found that neither drug caused any significant adverse events nor affected vital signs or clinical laboratory assessments.

A meta-analysis review published in Clinical Therapeutics Journal reported that while both Zyrtec and Allegra effectively alleviate allergy symptoms within an hour of ingestion, Zyrtec may be more potent at reducing skin-related symptoms such as hives or rashes due to its additional ability to block H1 histamine receptors on mast cells and basophils.

Although both are considered second-generation antihistamines with lower risk of causing drowsiness compared to their first-generation counterparts, some studies suggest that Zyrtec may cause mild sedation more frequently than Allegra. This is because Zyrtec crosses the blood-brain barrier more readily which can lead to greater interaction with central nervous system histamine receptors thereby potentially inducing drowsiness.

On balance though, whether one chooses Zyrtec or Allegra will often come down to personal preference since each person’s reaction to medication can differ significantly from others'. Both remain popular choices for allergies due largely to their rapid onset of action (within one hour), once-daily dosing requirement, minimal side effects profile including low potential for sedation.

abstract image of a researcher studying a bottle of drug.

At what dose is Zyrtec typically prescribed?

Oral dosages of Zyrtec for adults and children 6 years of age and older typically range from 5-10 mg/day, with the understanding that 10 mg/day is usually sufficient for treating symptoms associated with seasonal allergies or chronic hives. Children between the ages of 2 to 5 may be started on a dose as low as 2.5 mg/day depending on their body weight, and could be increased up to a maximum dosage of 5mg per day if needed. For Allegra, adults and children over the age of twelve are recommended an oral dosage ranging between 60-180mg/day. Children aged six to eleven should start at a lower dose, often around 30mg twice daily. The max dose should not exceed these guidelines in any case unless advised by a healthcare professional.

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At what dose is Allegra typically prescribed?

Allegra treatment typically begins at a dosage of 60 mg twice daily or 180 mg once daily for adults and children aged 12 years and older. For children aged between 2 to 11 years, the dose is usually started at 30 mg twice daily. The maximum recommended dose is generally not exceeded unless there's no significant improvement in allergy symptoms over time. Allegra doses are spaced evenly throughout the day, with at least a gap of approximately twelve hours between two dosages to ensure that its antihistamine properties effectively alleviate your allergic reactions consistently throughout the day.

What are the most common side effects for Zyrtec?

Common side effects for Zyrtec and Allegra include:

  • Drowsiness or sleepiness, more common with Zyrtec
  • Dry mouth
  • Nausea
  • Headache
  • Coughing
  • Diarrhea (more commonly associated with Zyrtec)
  • Fatigue or general tiredness

Less common but potential side effects include:

  • Insomnia (difficulty sleeping)
  • Nervousness
  • Rapid heartbeat or palpitations
  • Rash or allergic reactions such as hives.

It is important to note that these antihistamines generally do not cause sexual side effects, abnormal dreams, flu-like symptoms, pharyngitis, sinusitis, tremors or yawning. It's always best to consult your healthcare provider if you are experiencing any adverse reaction after taking medication.

abstract image of a patient experiencing side effect

Are there any potential serious side effects for Zyrtec?

While both Zyrtec and Allegra are generally well-tolerated, they can cause side effects in some individuals. In rare cases, potentially serious side effects may include:

  • Severe allergic reactions: hives, difficulty breathing, swelling of your face or throat
  • Unusual changes in mood or behavior: confusion, agitation, feeling restless or nervous
  • Rapid heart rate or palpitations
  • Problems with vision such as blurring or seeing halos around lights
  • Difficulty urinating - this could be a sign of an enlarged prostate gland

Additionally for Zyrtec specifically:

  • Drowsiness (more common than with Allegra)

And for Allegra:

  • Backache
  • Flu-like symptoms

If you experience any severe reactions like these while taking either medication, it's important to seek immediate medical attention.

What are the most common side effects for Allegra?

The use of Allegra (fexofenadine) can cause some common side effects, including:

  • Dry mouth and throat
  • Nausea or stomach discomfort
  • Headache or dizziness
  • Sleep disturbances such as insomnia
  • Occasional rapid heartbeat
  • Mild skin rash These are generally less severe than those experienced with other antihistamines. It's also important to note that unlike many allergy medications, Allegra does not typically cause confusion, agitation or anxiety. Moreover, weight loss and increased urination aren't common side effects of this drug either. As always, should you experience any unusual symptoms while taking Allegra, it is advised to consult your healthcare provider immediately.

Are there any potential serious side effects for Allegra?

Allegra, like any other medication, can cause adverse reactions in some patients. In rare cases, it may trigger severe side effects such as:

  • Difficulty breathing or swallowing
  • Swelling of the face, lips, tongue or throat (signs of a serious allergic reaction)
  • A skin rash which could be severe with blistering and peeling
  • Rapid heartbeat
  • Confusion and unusual behavior changes
  • Flushing (warmth, redness or tingly feeling under your skin)

If you encounter any of these symptoms after taking Allegra, cease its use immediately and contact your healthcare provider. It is essential to remember that while these instances are relatively rare compared to mild side effects like headache or dry mouth; they should not be ignored if experienced.

Contraindications for Zyrtec and Allegra?

Both Zyrtec and Allegra, like most other antihistamine medications, can potentially cause side effects. If you notice severe drowsiness, fast or irregular heartbeat, confusion, or problems with urination after taking these drugs, please seek immediate medical attention.

Neither Zyrtec nor Allegra should be taken if you are using certain types of antidepressants known as monoamine oxidase inhibitors (MAOIs). Always inform your doctor about all the medications that you're currently taking; MAOIs will require a period of about 2 weeks to clear from the system to prevent dangerous interactions with Zyrtec and Allegra.

How much do Zyrtec and Allegra cost?

For the brand name versions of these drugs:

  • The price for 30 tablets (10 mg each) of Zyrtec averages around $25–$35, which works out to approximately $0.83-$1.15/day, depending on your dose.
  • The price for 30 tablets (180 mg each) of Allegra is about $20–$30, working out to roughly $0.66-$1/day.

Thus, if you are taking one tablet per day as recommended by most doctors for both medications, Allegra tends to be slightly less expensive on a per-day treatment basis than Zyrtec. However, please remember that cost should not be your primary consideration in determining which antihistamine is right for you.

For the generic versions of these drugs:

  • Cetirizine hydrochloride (generic version of Zyrtec), available in packs from 14 up to 365 tablets with dosages at 10mg/tablet costs around $5 - $15 or so for smaller packs and can go up to ~$40+ for large pack counts like the yearly supply option; this equates between roughly $.03 - .07+/day when bought upfront.
  • Fexofenadine Hydrochloride (generic version of Allegra) is typically sold in packs ranging from 45 up towards larger bulk options similar as well with daily doses being consistent at near ~180mg/dose; prices vary but expect anywhere from ~$.06 - .09+/day depending upon quantity purchased and location they're bought at respectively.

Again though it's important reiterating that patients should consult their physicians or pharmacists before making a decision based primarily on price point alone since everyone responds differently potentially due individual body chemistry variations among other factors too numerous list here today even within same basic class drug type categories overall sometimes unfortunately requiring trial/error scenario attempts find best personalized fit ultimately end most importantly above all else regardless expense involved necessarily also factored equation too alongside efficacy concerns equally vital importance weigh justly balanced manner whenever contemplating such health-related decisions crucial nature inherently always without exception universally applicable across board no matter circumstances prevailing any given moment time inevitably invariably without fail consistently true beyond shadow doubt universally accepted medical consensus opinion professional community worldwide 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Popularity of Zyrtec and Allegra

Cetirizine, commonly known by its brand name Zyrtec, is a popular antihistamine used for the treatment of allergies. In 2020, it was estimated that about 6.2 million people in the US were prescribed cetirizine. This accounted for nearly 20% of all antihistamine prescriptions in the country and it has maintained steady prevalence over the past decade.

Fexofenadine, also recognized as Allegra, is another widely utilized antihistamine with approximately 4.8 million prescriptions filled in the US during 2020. It represents just over 15% of all antihistamine prescriptions nationally. While both medications are second-generation antihistamines and generally cause less drowsiness than first-generation options, fexofenadine is often chosen for those requiring symptom relief without any potential sedative effects because it's even less likely to cause drowsiness compared to cetirizine.

Conclusion

Both Zyrtec (cetirizine) and Allegra (fexofenadine) have established themselves as reliable options for relieving allergy symptoms, with extensive clinical studies backing their efficacy over placebo treatments. Both drugs function as antihistamines, blocking the action of histamine that causes allergic reactions. Due to differences in their structures and properties, they might be used under different circumstances.

Zyrtec is known for its rapid onset of action but may cause drowsiness in some individuals, making it less suitable for those who need to remain alert. On the other hand, Allegra has a slower onset but tends not to induce sleepiness due to minimal penetration of the central nervous system.

Both medications are available in generic forms which can lead to considerable cost savings for patients paying out-of-pocket. They also both require time before full effect is seen so an immediate relief from symptoms should not always be expected after taking the first dose.

The side effects between these two drugs are fairly comparable - generally well-tolerated with minor complaints like dry mouth or headaches being common. However, Zyrtec has a higher incidence rate of causing drowsiness than Allegra does. For both medicines, patients must monitor any unusual effects or worsening symptoms and should promptly seek medical help if adverse reactions occur.