Claritin (Loratadine) - Oral

What Is Claritin?

Claritin (loratadine) is an over-the-counter (OTC) medication used to treat symptoms of seasonal or year-round (perennial) allergies and hives in adults and children. It does not prevent hives or prevent or treat a serious allergic reaction (anaphylaxis).

Claritin is part of a class of drugs known as antihistamines. During an allergic reaction, your body releases histamine. When it binds to specific receptors in your body, histamine can cause allergy symptoms like itchy, watery eyes and a runny nose. Antihistamines work by decreasing the effects of histamine in your body.

Claritin is a second-generation antihistamine, which is a newer type of antihistamine. Newer antihistamines work just as well as second-generation ones but are not sedating.

Loratadine is available in tablets, chewable tablets, capsules, and syrup. Several brand-name loratadine products are available, including Claritin and Alavert. You can also find generic options.

Drug Facts

Generic Name: Loratadine

Brand Name(s): Alavert, Children's Claritin, Children's Clear-Atadine, Children's Dimetapp ND Allergy, Claritin, Claritin Reditabs, Clearatadine, Loradamed, Triaminic Allerchews

Drug Availability: Over-the-counter (OTC)

Administration Route: Oral

Therapeutic Classification: Antihistamine

Available Generically: Yes

Controlled Substance: N/A

Active Ingredient: Loratadine

Dosage Form(s): Tablet, capsule, syrup

What Is Claritin Used For?

As an antihistamine, Claritin is used to treat symptoms of allergic rhinitis (commonly called hay fever) from seasonal allergies or perennial allergies. These symptoms can include:

  • Runny nose
  • Sneezing
  • Itchy nose or throat
  • Watery eyes

Claritin can also treat itchy skin reactions and hives (urticaria).

Most loratadine products, including Claritin's tablets and capsules, can be used by adults and children 6 years and older. Children 2 years and older can take Claritin's chewable tablets or syrup.

How to Take Claritin

All forms of loratadine are meant to be taken by mouth. Read the labeling on the package for instructions on exactly how and when to take it.

Loratadine is available in many forms, including tablets, orally disintegrating tablets, syrups, and others. How much and how often you take loratadine may depend on the form it's in. Dosages will also differ based on age; children often need lower doses than adults.

If you are taking the orally disintegrating tablet, put it on or under your tongue where it will dissolve—you do not need to drink water with it. If using the syrup, use a proper dosing cup to measure the appropriate amount.

All loratadine products can be taken with or without food.


Store Claritin in a dry place at room temperature (68 F to 77 F). The medication can be exposed to temperatures as low as 36 F, but it's ideal to keep it at room temperature. Do not store it in the bathroom. The orally-disintegrating tablets should be used within six months of opening the foil pouch and immediately after opening an individual tablet blister.

How Long Does Claritin Take to Work?

Loratadine will typically work within one to three hours of taking it, and its effects will peak within eight to 12 hours. Loratadine's effects may last for 24 hours.

What Are the Side Effects of Claritin?

This is not a complete list of side effects, and others may occur. A healthcare provider can advise you on the possible side effects of taking loratadine. If you experience other side effects, contact your pharmacist or a healthcare provider. You may report side effects to the Food and Drug Administration (FDA) at or 1-800-FDA-1088.

Common Side Effects

The most common side effects of Claritin are:

  • Headaches
  • Drowsiness
  • Dry mouth
  • Fatigue

Tell your healthcare provider if these side effects are severe or do not go away.

Severe Side Effects

Call your healthcare provider immediately if you have serious side effects when taking Claritin. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency.

Serious side effects can include an allergic reaction to the medication. The signs and symptoms of an allergic reaction include:

  • Trouble breathing or swallowing
  • Rash
  • Itchiness
  • Swelling of the throat, eyes, lips, or tongue

Report Side Effects

Claritin may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your healthcare provider may send a report to the FDA's MedWatch Adverse Event Reporting Program or by phone (1-800-332-1088).

Dosage: How Much Claritin Should I Take?

Drug Content Provided and Reviewed by IBM Micromedex®

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For allergies:
    • For oral dosage form (chewable tablets, orally disintegrating tablets, tablets):
      • Adults and children 6 years of age and older—One tablet or 10 milligrams (mg) once a day. Do not take more than one tablet per day.
      • Children younger than 6 years of age—Use and dose must be determined by your doctor.
    • For oral dosage form (liquid-filled capsules):
      • Adults and children 6 years of age and older—One capsule or 10 milligrams (mg) once a day. Do not take more than one capsule per day.
      • Children younger than 6 years of age—Use and dose must be determined by your doctor.
    • For oral dosage form (solution):
      • Adults and children 6 years of age and older—2 teaspoonfuls or 10 milliliters (mL) once a day. Do not take more than 2 teaspoonfuls per day.
      • Children 2 to younger than 6 years of age—1 teaspoonful or 5 mL once day. Do not take more than 1 teaspoonful per day.
      • Children younger than 2 years of age—Use and dose must be determined by your doctor.


Dosing adjustments may be needed in some cases. Your healthcare provider may advise modified dosing if you have liver or kidney problems. Talk to them about how to safely take Claritin.

Missed Dose

If you miss a dose of Claritin, take the missed dose as soon as you remember. Do not take extra to make up for the missed dose. Doing so can increase your risk for side effects.

Overdose: What Happens If I Take Too Much Claritin?

If you take too much loratadine, you may experience:

  • Extreme sleepiness
  • Rapid heart rate (tachycardia)
  • Headache

Children who have taken too much Claritin syrup may experience what is called extrapyramidal side effects including muscle stiffness, tremors, involuntary muscle movements, and palpitations.

What Happens If I Overdose on Claritin?

If you think you or someone else may have overdosed on Claritin, call a healthcare provider or the Poison Control Center (1-800-222-1222).

If someone collapses or isn't breathing after taking Claritin, call 911 immediately.


Drug Content Provided and Reviewed by IBM Micromedex®

If your or your child's condition do not improve within a few days, or if they become worse, check with your doctor.

What Are Reasons I Shouldn’t Take Claritin?

There are a few reasons why you may not be able to take Claritin.


Do not take loratadine if you are allergic to the drug or any of its ingredients.


Alcohol and antihistamines can affect the central nervous system. Both substances can leave you feeling drowsy or lightheaded. Using alcohol and Claritin together may enhance these effects. It is recommended that you avoid alcohol while taking an antihistamine.


Claritin is considered safe to take while pregnant; however, there are no studies on its use in pregnant people. Talk to your healthcare provider if you have any questions or concerns about using this medication while pregnant


Loratadine is not expected to cause any negative effects in breastfed infants. However, the drug may affect lactation, especially when used in combination with pseudoephedrine. If you are breastfeeding, talk to your healthcare provider about whether Claritin is appropriate for you or if there are alternative allergy medications that would be a better choice.


Claritin is not indicated for use in children younger than 2.

Other Health Conditions

People may react to Claritin differently based on their medical history. Tell your healthcare provider if you have liver or kidney problems.

What Other Medications Interact With Claritin?

Claritin is generally safe and has a low risk of severe drug interactions. However, there still are a few medications that may interact with Claritin, including:

  • Tagamet (cimetidine)
  • Ketoconazole
  • Erythromycin

This list does not include all the drugs that may interact with loratadine. Before taking loratadine, tell your healthcare provider about all of the prescription medications, OTC medications, vitamins, supplements, or herbs you are taking. Knowing this information, your provider can help you avoid potential interactions between loratadine and other medicines or products you are taking. If you have any questions about drug interactions, ask your provider or pharmacist.

What Medications Are Similar?

There are a few types of antihistamines that are available over the counter (OTC). Some cause more drowsiness than others. Below is a list of other commonly used OTC antihistamines:


Diphenhydramine is another type of antihistamine. It is often used to treat allergy symptoms (e.g., itchy or watery eyes, sneezing, itchy throat) and hives. Benadryl is available as an oral tablet, a chewable tablet, an orally disintegrating tablet, a capsule, and a liquid. It is also available in topical forms, such as gels, creams, or sprays, to help treat allergic skin reactions.

Common side effects of diphenhydramine include dry mouth, drowsiness, or headache. Benadryl tends to cause more drowsiness than Claritin.


Fexofenadine is another medication classified as an antihistamine. It is often used to treat allergy symptoms, hives, and skin rash. Common side effects of fexofenadine include headache, dizziness, upset stomach, diarrhea, or pain in your arms, legs, or back.

You need to avoid drinking fruit juice while taking Allegra. Fruit juice can make this drug less effective.


Cetirizine is another medication classified as an antihistamine. It is very similar to Claritin. Cetirizine is often prescribed to treat allergy symptoms as well as redness and itchiness from hives. Common side effects from cetirizine include drowsiness, headache, or stomach pain.

This is a list of drugs from similar classes of medication as Claritin. It is not a list of drugs recommended to take with Claritin. Talk to your pharmacist or healthcare provider if you have any questions.

Frequently Asked Questions

  • What is Claritin used for?

    Claritin is an over-the-counter (OTC) medication that is used to treat allergy symptoms such as watery eyes, itching, runny nose, or sneezing. It can also treat skin-related allergy reactions, like hives.

  • What are the side effects of Claritin?

    The most common side effects of Claritin are headaches, drowsiness, fatigue, and dry mouth. More severe side effects of Claritin include an allergic reaction, which can cause symptoms like rash, swelling of the throat, eyes, lips, or tongue, and trouble breathing or swallowing.

    Call your healthcare provider immediately if you are experiencing serious side effects. Call 911 if you are having a medical emergency or life-threatening symptoms.

  • How does Claritin work?

    Claritin is an antihistamine. When it binds to certain receptors in the body, histamine can cause allergy symptoms. Antihistamines work by decreasing the effect of histamine on those receptors, which helps treat allergy symptoms.

How Can I Stay Healthy While Taking Claritin?

Claritin is a safe and effective medication that is often used to treat allergy symptoms and hives.

The most common side effects of Claritin are mild and include drowsiness or headaches. However, more severe side effects can occur if you are allergic to loratadine or any ingredients in the product.

Reducing your exposure to your allergy triggers—for example, allergens like pollen or pet dander—can help manage or prevent allergy symptoms. However, avoiding allergens may not be enough, which is when medications like Claritin can help. If your condition is uncontrolled or severe, allergy shots (a form of immunotherapy) are another option.

While Claritin is an OTC drug, it is still a good idea to consult your healthcare provider or a pharmacist before taking it if you have certain health conditions or are taking other medications. This way, they can let you know if you should modify how you take it to avoid interactions.

Medical Disclaimer

Verywell Health's drug information is meant for educational purposes only and is not intended to replace medical advice, diagnosis, or treatment from a healthcare provider. Consult your healthcare provider before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

10 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Food and Drug Administration. Claritin (brand of loratadine) Label.

  2. Church MK. Allergy, histamine and antihistamines. Handb Exp Pharmacol. 2017;241:321-331. doi:10.1007/164_2016_85

  3. Prescribers' Digital Reference. Loratadine- drug summary.

  4. National Institute on Alcohol Abuse and Alcoholism. Harmful interactions.

  5. Drugs and Lactation Database (LactMed) [Internet]. Bethesda (MD): National Library of Medicine (US); 2006-. Loratadine.

  6. National Library of Medicine. Label: Benadryl- diphenhydramine hydrochloride tablet, film coated.

  7. National Library of Medicine. Label: Allegra Allergy- fexofenadine hydrochloride tablet, film coated.

  8. Bailey DG. Fruit juice inhibition of uptake transport: a new type of food-drug interaction. Br J Clin Pharmacol. 2010 Nov;70(5):645-55. doi:10.1111/j.1365-2125.2010.03722.x

  9. National Library of Medicine. Label: Zyrtec Allergy- cetirizine hydrochloride tablet, film coated.

  10. deShazo RD, Kemp SF. Patient education: trigger avoidance in allergic rhinitis (beyond the basics).

By Kaylea Swearingen, PharmD
Kaylea Swearingen is a registered pharmacist and health and wellness writer.