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Cetirizine vs. Loratadine: Your Guide to Allergy Relief

Written by Andrew Le, MD

UpdatedFebruary 29, 2024

Cetirizine and loratadine are the most commonly prescribed second-generation antihistamines for treating allergy symptoms. Both medications block histamine receptors, reducing allergy symptoms like sneezing, itchy eyes, and runny nose.

However, there are some notable differences between these drugs. One study found that cetirizine better relieved seasonal allergy symptoms than loratadine. Cetirizine worked faster and was more effective overall at controlling symptoms. It did cause more drowsiness than loratadine (13% vs. 2%) but resulted in fewer headaches (11% vs 23%).

This guide examines the key similarities and differences between cetirizine and loratadine in terms of efficacy, side effects, dosage, and cost. Understanding how these common allergy medications compare can help determine the best treatment option.

🔑 Key Takeaways

  • Cetirizine worked faster and was more effective overall at controlling allergy symptoms than loratadine in one study. However, cetirizine caused more drowsiness.
  • Both cetirizine and loratadine are second-generation antihistamines that block histamine receptors to relieve allergy symptoms like sneezing, itchy eyes, and runny nose.
  • Cetirizine has shown effectiveness comparable to or greater than other antihistamines in treating allergic disorders in adults and children.
  • Studies found loratadine significantly more effective than placebo and comparable to other antihistamines like terfenadine in relieving seasonal and perennial allergic rhinitis symptoms.
  • Drowsiness is the most common side effect of both medications, but cetirizine is more likely to cause this effect.
  • The standard adult dosage is 10mg once daily for both medications. Liquid forms are available for children at lower doses based on age.
  • Cetirizine and loratadine have similar pricing for generic versions, around $10-15 for 30 tablets. Prices may be even lower with coupons and discount cards.
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1. Overview

People commonly use antihistamines to treat allergy symptoms, with cetirizine and loratadine being two of the most popular options. Let’s explore below the key similarities and differences between these medications.

Cetirizine

Cetirizine is designed to reduce the impact of the natural chemical histamine in the body. This reduction in histamine levels helps alleviate symptoms such as sneezing, itching, watery eyes, and a runny nose, commonly associated with allergies.

Cetirizine is extensively used to treat allergy symptoms like:

Moreover, it manages allergic reactions, itching, and swelling caused by chronic urticaria (hives).

Cetirizine's efficacy extends to minimizing or eliminating symptoms related to:

As a second-generation antihistamine, cetirizine is known to be less likely to induce sleepiness than some other antihistamines like Benadryl. It is available in various forms, including tablets, capsules, and liquid formulations, and can be obtained over the counter with a prescription.

Common brand names include:

  • All Day Allergy
  • Allergy Relief
  • Zyrtec
  • Zyrtec Hives Relief

Loratadine

Loratadine operates by reducing the effects of histamine in the body. Loratadine is commonly used to treat various symptoms caused by allergies, including:

  • Sneezing
  • Runny nose
  • Watery eyes
  • Hives
  • Skin rash
  • Hay fever
  • Itching

Additionally, it effectively manages skin hives and itching in individuals with chronic skin reactions.

Loratadine belongs to the antihistamine group and works by blocking histamine released by the body during an allergic reaction. It is available in various forms, such as tablets, capsules, and liquid formulations, and can be purchased over the counter.

Common brand names for loratadine include:

  • Alavert
  • Allergy Relief
  • Claritin
  • Claritin Hives Relief
  • Claritin Liqui-Gel
  • Claritin-D 24 Hour
  • Clear-Atadine
  • QlearQuil All Day & All Night Allergy Relief
  • Quality Choice Allergy Relief Non-Drowsy
  • Tavist ND

It is advisable to consult healthcare providers or pharmacists for any questions or concerns regarding its usage.

2. Efficacy For Allergy Symptoms

Understanding how effective different antihistamines are for relieving allergy symptoms can inform treatment choices. See below for the efficacy comparisons between cetirizine and loratadine, revealing notable differences that could sway medication selection.

Cetirizine

Studies indicate that cetirizine is on par with or even more effective than conventional dosages of other antihistamines like ebastine, fexofenadine, loratadine, and mizolastine in adults with allergic disorders. The rapid onset of action and sustained relief provided by cetirizine make it a valuable option for managing allergic rhinitis and urticaria symptoms.

In pediatric patients, cetirizine has demonstrated effectiveness comparable to or greater than other antihistamines in short-term and long-term treatment. Additionally, cetirizine has shown promise in reducing symptoms of allergic asthma in adults and decreasing the risk of asthma development in infants with atopic dermatitis sensitized to specific allergens.

Cetirizine's pharmacokinetic characteristics, including rapid absorption, high plasma protein binding, and renal excretion, contribute to its effectiveness in providing long-lasting relief from allergy symptoms. The various formulations of cetirizine, such as tablets, capsules, solutions, and orally disintegrating tablets, offer flexibility in dosing for individualized treatment.

Loratadine

In a 14-day, double-blind, randomized study on seasonal allergic rhinitis, 317 patients received loratadine (10 mg once daily), terfenadine (60 mg twice daily), or placebo. The study found that loratadine significantly decreased mean total scores of combined nasal and non-nasal allergy symptoms by 46%, compared to 44% with terfenadine and 35% with placebo.

Loratadine effectively relieves nasal discharge, sneezing, and itching/burning eyes. The therapeutic response to loratadine was good or excellent in 64% of patients, compared to 56% with terfenadine and 47% with placebo.

Adverse experiences were mild or moderate, with sedation reported by 10 loratadine-treated patients, 7 terfenadine-treated patients, and 8 placebo-treated patients. The study concluded that loratadine was comparable to terfenadine and significantly superior to placebo in relieving seasonal allergic rhinitis symptoms.

Similarly, loratadine was evaluated for its efficacy and safety in 228 patients with perennial allergic rhinitis. At 10 mg once daily, loratadine was significantly more effective than placebo and comparable to terfenadine (60 mg twice daily) in reducing combined symptom scores. The study spanned 28 days, and loratadine's efficacy was maintained throughout the treatment. The overall incidence of side effects with loratadine was low (14%), with few occurrences of sedation (3%) and dry mouth (4%).

The drug's onset of action is rapid, with effects peaking within 8 to 12 hours and elimination through fecal and renal routes. Loratadine has a half-life of approximately 8 hours, and its active metabolite's half-life is 28 hours.

In a study evaluating loratadine as prophylactic therapy for seasonal allergic rhinitis, 118 subjects received loratadine (10 mg once daily) or placebo for six weeks. Loratadine effectively suppresses symptoms and gives patients more symptom-free days throughout the pollen season than a placebo.

The study found that 65% of loratadine subjects had no symptoms or mild rhinitis at the end of the study, compared to 49% with placebo. The incidence of sedation and anticholinergic effects was comparable between the groups.

3. Side Effects

Antihistamines may cause side effects, essential for safe usage. Below are the potential side effects of cetirizine and loratadine, enabling informed decisions and proper precautions.

Cetirizine

Like all medications, it comes with potential side effects. Awareness of these effects is crucial to ensure safe and effective treatment.

Common Side Effects

The most prevalent side effect of cetirizine is drowsiness, affecting more than 1 in 10 individuals. Other common side effects, occurring in more than 1 in 100 people, include:

It's worth noting that children are more likely to experience diarrhea, sneezing, or nasal congestion than adults.

Serious Side Effects

While serious side effects are rare, they can occur. Immediate medical attention is required if you experience bruising or bleeding beyond normal levels. In extremely rare cases, a serious allergic reaction (anaphylaxis) can occur, characterized by symptoms such as:

How to Cope with Side Effects

If you encounter common side effects, several strategies can help manage them:

  • Drowsiness: Consider trying a different non-drowsy antihistamine. Consult your doctor if the issue persists.
  • Headaches: Rest, stay hydrated, and avoid excessive alcohol consumption. Consult your doctor if headaches persist beyond a week.
  • Dry Mouth: Chew sugar-free gum or suck on sugar-free sweets.
  • Nausea: Take tablets with food and choose simple meals, avoiding rich or spicy foods.
  • Dizziness: Stand up slowly and avoid driving or using machinery if dizziness occurs.

Cautions with Other Medicines

Some medications may increase the likelihood of cetirizine's side effects. To ensure safe usage, it's crucial to inform your doctor or pharmacist about any other medications, including herbal remedies and supplements.

Loratadine

Like Cetirizine, Loratidine may also come with side effects. Understanding these effects is vital for a safe and successful treatment.

Common Side Effects

Loratadine's primary common side effect is drowsiness, affecting more than 1 in 100 people. In children, additional common side effects may include:

Serious Side Effects

While serious side effects are rare, loratadine can, in rare cases, trigger a serious allergic reaction (anaphylaxis). Symptoms include:

  • Swelling of the lips
  • Difficulty breathing
  • Throat tightness
  • Skin discoloration
  • Confusion
  • Fainting

How to Cope with Side Effects

If common side effects occur, consider the following:

  • Drowsiness: Experiment with a different non-drowsy antihistamine and consult your doctor if necessary.
  • Headaches: Rest, stay hydrated, and consult your pharmacist for recommended painkillers.
  • Fatigue or Nervousness: Discuss persistent side effects with your doctor or pharmacist for potential alternatives.

Cautions with Other Medicines

Inform your healthcare provider about any medications, including herbal remedies and supplements, as some may interact with loratadine and exacerbate its side effects.

4. Dosage

Properly dosing antihistamines is vital for optimizing benefits and risks. The recommended dosages for cetirizine and loratadine are outlined below, offering helpful guidance for safe, effective treatment.

Cetirizine

Cetirizine comes in tablets and capsules with a strength of 10mg and a liquid form labeled either 5mg/5ml or 1mg/1ml. The typical adult dose is 10mg once a day for the relief of symptoms associated with allergic rhinitis or chronic idiopathic urticaria.

The maximum dosage should not exceed 10mg per day. For children aged 6 to 11 years, the recommended dose is 5mg twice a day, leaving a 10 to 12-hour gap between doses.

Children aged 2 to 5 years are advised to take 2.5mg twice daily. The dosage for children aged 1 to 2 years is individualized based on weight or age.

Cetirizine can be taken with or without food, and the tablets or capsules should be swallowed whole with water, milk, or squash. The liquid form may be more convenient for children and comes with a plastic syringe or spoon to ensure the correct dosage. The timing of cetirizine intake depends on the situation, whether it's taken on days with symptoms triggered by allergens or regularly to prevent symptoms.

If a dose is forgotten, taking it as soon as remembered is recommended unless it's close to the next scheduled dose. However, doubling up on doses should be avoided. Cetirizine is generally considered safe, and an accidental overdose is unlikely to cause harm. In case of concerns or common side effects, contact a doctor.

Loratadine

Loratadine is available in 10mg tablets and as a liquid labeled 5mg/5ml or 1mg/1ml. The standard adult dose is 10mg once a day to relieve symptoms associated with hay fever or other upper respiratory allergies, with a maximum recommended dose of 10mg per day.

Children aged 2 to 5 years are advised to take 5mg once a day, while those aged six years and older can take 10mg once a day.

Loratadine can be taken with or without food and comes in ordinary melt-in-the-mouth tablets. The chewable tablet should be chewed before swallowing, while the melt-in-the-mouth tablet dissolves instantly on the tongue. The timing of loratadine intake depends on whether it's taken for symptomatic relief or prevention.

If a dose is forgotten, it should be taken as soon as remembered unless it's close to the next scheduled dose. Doubling up on doses is not recommended.

Loratadine is generally considered safe, and an overdose is unlikely to cause harm. In case of concerns or symptoms, contacting a doctor is recommended. Always follow your doctor's instructions and consult them for any questions or concerns about the dosage.

5. Cost

According to Drugs.com, here is the current pricing information for Cetirizine and Loratadine, two widely used antihistamines:

Cetirizine

Cetirizine offers various formulations to cater to different preferences. The estimated prices are as follows:

  • Oral Tablet 10 mg: $11 for 30 tablets
  • Oral Liquid 1 mg/mL: $19.16 for 118 milliliters
  • Oral Syrup 1 mg/mL: $14.44 for 118 milliliters
  • Oral Tablet, Chewable 5 mg: $39.13 for 30 tablets
  • Oral Tablet, Chewable 10 mg: $49.88 for 30 tablets

Loratadine

The estimated prices for various loratadine formulations are as follows:

  • Oral Tablet 10 mg: $10 for 10 tablets
  • Oral Syrup 5 mg/5 mL: $12.45 for 118 milliliters
  • Oral Tablet, Chewable 5 mg: $26.84 for 30 tablets
  • Oral Tablet, Disintegrating 10 mg: $11.16 for 10 tablets
See prices for Cetirizine on Amazon
See prices for Loratadine on Amazon

3. Side Effects

Antihistamines may cause side effects, essential for safe usage. Below are the potential side effects of cetirizine and loratadine, enabling informed decisions and proper precautions.

Cetirizine

Like all medications, it comes with potential side effects. Awareness of these effects is crucial to ensure safe and effective treatment.

Common Side Effects

The most prevalent side effect of cetirizine is drowsiness, affecting more than 1 in 10 individuals. Other common side effects, occurring in more than 1 in 100 people, include:

It's worth noting that children are more likely to experience diarrhea, sneezing, or nasal congestion than adults.

Serious Side Effects

While serious side effects are rare, they can occur. Immediate medical attention is required if you experience bruising or bleeding beyond normal levels. In extremely rare cases, a serious allergic reaction (anaphylaxis) can occur, characterized by symptoms such as:

How to Cope with Side Effects

If you encounter common side effects, several strategies can help manage them:

  • Drowsiness: Consider trying a different non-drowsy antihistamine. Consult your doctor if the issue persists.
  • Headaches: Rest, stay hydrated, and avoid excessive alcohol consumption. Consult your doctor if headaches persist beyond a week.
  • Dry Mouth: Chew sugar-free gum or suck on sugar-free sweets.
  • Nausea: Take tablets with food and choose simple meals, avoiding rich or spicy foods.
  • Dizziness: Stand up slowly and avoid driving or using machinery if dizziness occurs.

Cautions with Other Medicines

Some medications may increase the likelihood of cetirizine's side effects. To ensure safe usage, it's crucial to inform your doctor or pharmacist about any other medications, including herbal remedies and supplements.

Loratadine

Like Cetirizine, Loratidine may also come with side effects. Understanding these effects is vital for a safe and successful treatment.

Common Side Effects

Loratadine's primary common side effect is drowsiness, affecting more than 1 in 100 people. In children, additional common side effects may include:

Serious Side Effects

While serious side effects are rare, loratadine can, in rare cases, trigger a serious allergic reaction (anaphylaxis). Symptoms include:

  • Swelling of the lips
  • Difficulty breathing
  • Throat tightness
  • Skin discoloration
  • Confusion
  • Fainting

How to Cope with Side Effects

If common side effects occur, consider the following:

  • Drowsiness: Experiment with a different non-drowsy antihistamine and consult your doctor if necessary.
  • Headaches: Rest, stay hydrated, and consult your pharmacist for recommended painkillers.
  • Fatigue or Nervousness: Discuss persistent side effects with your doctor or pharmacist for potential alternatives.

Cautions with Other Medicines

Inform your healthcare provider about any medications, including herbal remedies and supplements, as some may interact with loratadine and exacerbate its side effects.

4. Dosage

Properly dosing antihistamines is vital for optimizing benefits and risks. The recommended dosages for cetirizine and loratadine are outlined below, offering helpful guidance for safe, effective treatment.

Cetirizine

Cetirizine comes in tablets and capsules with a strength of 10mg and a liquid form labeled either 5mg/5ml or 1mg/1ml. The typical adult dose is 10mg once a day for the relief of symptoms associated with allergic rhinitis or chronic idiopathic urticaria.

The maximum dosage should not exceed 10mg per day. For children aged 6 to 11 years, the recommended dose is 5mg twice a day, leaving a 10 to 12-hour gap between doses.

Children aged 2 to 5 years are advised to take 2.5mg twice daily. The dosage for children aged 1 to 2 years is individualized based on weight or age.

Cetirizine can be taken with or without food, and the tablets or capsules should be swallowed whole with water, milk, or squash. The liquid form may be more convenient for children and comes with a plastic syringe or spoon to ensure the correct dosage. The timing of cetirizine intake depends on the situation, whether it's taken on days with symptoms triggered by allergens or regularly to prevent symptoms.

If a dose is forgotten, taking it as soon as remembered is recommended unless it's close to the next scheduled dose. However, doubling up on doses should be avoided. Cetirizine is generally considered safe, and an accidental overdose is unlikely to cause harm. In case of concerns or common side effects, contact a doctor.

Loratadine

Loratadine is available in 10mg tablets and as a liquid labeled 5mg/5ml or 1mg/1ml. The standard adult dose is 10mg once a day to relieve symptoms associated with hay fever or other upper respiratory allergies, with a maximum recommended dose of 10mg per day.

Children aged 2 to 5 years are advised to take 5mg once a day, while those aged six years and older can take 10mg once a day.

Loratadine can be taken with or without food and comes in ordinary melt-in-the-mouth tablets. The chewable tablet should be chewed before swallowing, while the melt-in-the-mouth tablet dissolves instantly on the tongue. The timing of loratadine intake depends on whether it's taken for symptomatic relief or prevention.

If a dose is forgotten, it should be taken as soon as remembered unless it's close to the next scheduled dose. Doubling up on doses is not recommended.

Loratadine is generally considered safe, and an overdose is unlikely to cause harm. In case of concerns or symptoms, contacting a doctor is recommended. Always follow your doctor's instructions and consult them for any questions or concerns about the dosage.

5. Cost

According to Drugs.com, here is the current pricing information for Cetirizine and Loratadine, two widely used antihistamines:

Cetirizine

Cetirizine offers various formulations to cater to different preferences. The estimated prices are as follows:

  • Oral Tablet 10 mg: $11 for 30 tablets
  • Oral Liquid 1 mg/mL: $19.16 for 118 milliliters
  • Oral Syrup 1 mg/mL: $14.44 for 118 milliliters
  • Oral Tablet, Chewable 5 mg: $39.13 for 30 tablets
  • Oral Tablet, Chewable 10 mg: $49.88 for 30 tablets

Loratadine

The estimated prices for various loratadine formulations are as follows:

  • Oral Tablet 10 mg: $10 for 10 tablets
  • Oral Syrup 5 mg/5 mL: $12.45 for 118 milliliters
  • Oral Tablet, Chewable 5 mg: $26.84 for 30 tablets
  • Oral Tablet, Disintegrating 10 mg: $11.16 for 10 tablets
See prices for Cetirizine on Amazon
See prices for Loratadine on Amazon

📓 Health Note

These prices are approximate and may vary depending on the pharmacy you visit. Additionally, discounts may be available through the Drugs.com Discount Card, saving you up to 80% or more of the cost of these medications. Remember that these prices are for cash-paying customers and may not be valid with insurance plans. You may be eligible for discounts with specific coupons, copay cards, or rebate offers.

Wrap Up

Cetirizine and loratadine are effective second-generation antihistamines commonly used to treat allergy symptoms.

Cetirizine provides faster, longer-lasting relief but is more likely to cause drowsiness. Loratadine has a lower side effect profile but may not control symptoms as extensively.

The standard daily dosage for adults is 10mg for both medications, with liquid forms available for children. Generic versions of cetirizine and loratadine are reasonably priced, costing about $10-15 for a month's supply.

Both offer valuable options for managing allergy symptoms, with cetirizine potentially providing more robust relief and loratadine having fewer side effects.

FAQs on Cetirizine and Loratadine

Which is better, cetirizine or loratadine?

In terms of user ratings on Drugs.com, cetirizine holds a slightly higher average score of 5.8 out of 10 from 289 reviews, with 46% reporting positive effects. On the other hand, loratadine averages a score of 4.7 out of 10 from 137 ratings. Based on user feedback, cetirizine has a slight edge.

Which antihistamine is the most effective?

Among second-generation antihistamines, Zyrtec stands out as the strongest and most effective. Of note, the first-generation antihistamine Benadryl is highly effective, but its tendency to cause drowsiness can be limiting unless used as a sleep aid.

Can you take two different antihistamines in a day?

It's generally safe to combine allergy medications from different classes. For instance, nasal steroids and oral decongestants can be taken together. However, combining oral antihistamines, such as Zyrtec and Benadryl, without consulting a healthcare provider is not recommended.

Can I take loratadine twice a day?

Loratadine comes in tablet form, and it's intended to be taken once daily for allergy symptom relief. It's crucial to stay within one dose in 24 hours to ensure safe usage.

Illustration of a healthcare provider asking questions on a smart phone.
Allergy treatment - Online visit
Get virtual care from a licensed clinician—no appointment needed
Illustration of a healthcare provider asking questions on a smart phone.
  • $29 one-time assessment
  • No video call or appointment necessary
  • Personalized treatment plan prescribed for your condition