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Zyrtec and Claritin are similar over-the-counter allergy medicines. Your choice may come down to a subtle difference.

Among the most popular over-the-counter (OTC) allergy meds are Zyrtec and Claritin. These two allergy drugs produce very similar results. They both calm your immune system’s reaction to allergens.

However, the potential side effects are different. They also take effect at different times and stay effective for different durations. These factors could determine which of these two drugs is better for you.

These drugs have different active ingredients. The active ingredient in Zyrtec is cetirizine. In Claritin, it’s loratadine. Both cetirizine and loratadine are nonsedating antihistamines.

Antihistamines have a reputation of making you sleepy because the first types crossed into your central nervous system more easily and had a direct effect on your alertness. However, newer antihistamines like Zyrtec and Claritin are less likely to cause this side effect.

Claritin is long acting. Most people experience at least 24 hours of relief after a single dose. Zyrtec, on the other hand, is fast acting. People who take it may feel relief in as little as one hour.

Antihistamines like Zyrtec and Claritin are designed to calm the histamine reaction your body has when it’s exposed to an allergen. When your body encounters something it’s allergic to, it sends out white blood cells and goes into fight mode. It also releases a substance called histamine. This substance causes many of the symptoms of an allergic reaction.

Antihistamines are designed to block the effects of the histamine that your body produces. In turn, they decrease the symptoms of the allergy.

Zyrtec and Claritin have very few side effects and are generally recognized as safe for most people. However, some side effects may still occur.

Zyrtec can cause sleepiness, but only in some people. Take it for the first time when you will be at home for a few hours in case it makes you sleepy. Claritin is less likely to cause sleepiness than Zyrtec when you take either at recommended doses.

Shared side effects

Mild side effects caused by both medications include:

More serious side effects of these medications are rare. If you have one of the following side effects after taking either medication, seek emergency medical attention:

In children

Children may have any of the side effects that adults do, but they can also have completely different reactions to antihistamines. Children may become stimulated, restless, or sleepless. However, if you give your children a dose of either drug that’s too large, they can become groggy.

Claritin and Zyrtec both come in the same forms:

  • solid tablets
  • chewable tablets
  • dissolving tablets
  • gel capsules
  • oral solution
  • oral syrup

The dosage depends on your age and the severity of your symptoms.

Claritin is active in the body for at least 24 hours. The typical daily dose of Claritin for adults and children who are 6 years and older is 10 mg per day. For Zyrtec, it’s 5 mg or 10 mg. The typical daily dose of Claritin for children aged 2–5 years is 5 mg. Children this age using Zyrtec should be given 2.5–5 mg.

People with chronic medical conditions like kidney disease may need less frequent doses because the drug may take longer for them to process. Older adults and adults who have chronic illness should only take 5 mg of Zyrtec per day. For the best possible results, check with your doctor or pharmacist before deciding what dose to use.

In children

Remember that children may be different sizes at different ages, so when in doubt, start with a smaller dose. For the best results, talk to your child’s doctor or a pharmacist before deciding what dose to give your child. And always check the package for dosing guidelines.

Zyrtec and Claritin are both priced about the same. They’re available over the counter, so prescription drug insurance will likely not cover any portion of their expense. However, manufacturer coupons are often available for both medications. This will reduce your overall cost.

Generic versions of both antihistamines are readily available, as well. They’re often less expensive than the brand-name versions, and new forms and flavors often appear. Be sure to read the generic medication’s label to confirm you are getting the right type of active ingredient.

Both Zyrtec and Claritin may make you drowsy or tired. For that reason, you shouldn’t take these medications if you also take muscle relaxers, sleeping pills, or other drugs that cause drowsiness. Taking them at the same time that you take sedating drugs can make you extremely sleepy.

Do not take either of these medicines and then consume alcohol. Alcohol may multiply side effects and make you dangerously drowsy.

Both Zyrtec and Claritin are effective over-the-counter allergy relief drugs. If your choice has brought you to down to these two drugs, you may ask yourself, will drowsiness have an impact on my daily routine?

If the answers to this question doesn’t bring you closer to an answer, ask your doctor or pharmacist for a recommendation. If you find that the recommended medicine works well, stick with it. If it doesn’t, try the other. If none of the OTC options seem to help, see an allergist. You may need a different course of treatment for your allergies.

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