Cetirizine vs. Loratadine for Allergic Rhinitis: Important Differences and Potential Risks.

Key takeaways

Cetirizine (Zyrtec) and loratadine (Claritin) are both antihistamines used to relieve allergy symptoms like runny nose and watery eyes, but they have some key differences. Cetirizine is available both over-the-counter and by prescription, while loratadine is only available over-the-counter. Cetirizine can cause sleepiness, but it's less likely to do so compared to first-generation antihistamines like diphenhydramine (Benadryl). Loratadine is considered a non-drowsy option, though it can still cause some drowsiness. Cetirizine is safe for use during pregnancy, whereas loratadine is not the first-choice option for pregnant individuals. Both medications are taken once daily, but cetirizine starts working within 20 to 60 minutes, while loratadine may take 1 to 3 hours to start working and up to 12 hours for full effects. Additionally, cetirizine is approved for treating chronic hives in children, whereas loratadine is not specifically indicated for this use.

See more from our pharmacists

Zyrtec Vs. Claritin Vs. Allegra: Which Works Best For Allergies?

Cetirizine

(Zyrtec)

Get free coupons

Loratadine

(Claritin)

Get free coupons

Summary for Cetirizine

Prescription or over-the-counter

Cetirizine (Zyrtec) is an antihistamine. It's used for relief of allergy symptoms, such as runny nose or watery eyes, in adults and children. Cetirizine (Zyrtec) is also a safe option for people who are pregnant. This medication is available in different formulations, including tablets and liquid solutions. Typically, cetirizine (Zyrtec) is taken by mouth once per day. The most common side effect of cetirizine (Zyrtec) is sleepiness. But it's less likely to make you drowsy compared to some other antihistamines, such as diphenhydramine (Benadryl).

Indications for Cetirizine

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

Pros and Cons for Cetirizine

Pros

First-choice option for relieving allergy symptoms
Taken once per day
Available in several formulations (e.g., pills, chewable tablets, orally disintegrating tablets, liquids)
Safe to take while pregnant

Cons

Can cause you to feel sleepy
Higher risk of side effects in people with liver or kidney problems
Pills can't be used in children younger than 6 years.

Common Side Effects for Cetirizine

People 12 years of age and older:

Sleepiness (14%)
Tiredness (6%)
Dry mouth (5%)

Children age 6 to under 12 years:

Headache (11-14%)
Sore throat (3-6%)
Stomach pain (4-6%)
Cough (3-4%)
Sleepiness (2-4%)

Warnings for Cetirizine

Sleepiness
Accidentally taking too much medication

Summary for Loratadine

Over-the-counter

Loratadine (Claritin) is an over-the-counter antihistamine for adults and kids. It helps relieve allergy symptoms like a runny nose, sneezing, and watery eyes. This allergy medication is taken by mouth, usually once a day. It comes as different formulations, including regular tablets, chewable tablets, and a liquid. Loratadine (Claritin) is a non-drowsy allergy medication because it's less likely to make you sleepy. Other side effects can include headache and feeling tired. Loratadine (Claritin) is available as a brand-name and generic.

Indications for Loratadine

Short-term relief of allergy symptoms (runny nose, itchy nose or throat, itchy or watery eyes)

Pros and Cons for Loratadine

Pros

First-choice option for allergies
Tends to cause less sleepiness than some other antihistamines like diphenhydramine (Benadryl)
Liquid form and some chewable tablets okay for children as young as 2 years old to take

Cons

Can take 1 to 3 hours to start working
Regular tablets and quick-dissolving tablets not for children younger than 6
Might have a higher risk of side effects if you have liver or kidney problems

Common Side Effects for Loratadine

Headache (12%)
Sleepiness (8%)
Feeling tired (4%)
Dry mouth (3%)

Warnings for Loratadine

Sleepiness
Accidentally taking too much medication
Caution use in people with phenylketonuria (PKU) - chewable tablets and orally disintegrating tablets