Side Effects of Loratadine Overdose

Updated April 17, 2017

Loratadine is an over-the-counter antihistamine sold under many trade names, including Claritin. It is used to control symptoms of allergic rhinitis (seasonal allergies) and chronic urticaria (hives). Recommended loratadine dosage for adults and children 6 and older is 10 mg (in either tablet, syrup or dissolving tablet form). For children age 2 to 5, the recommended dosage is 5 mg in syrup form. Doses in excess of these amounts are considered overdoses.

Reasons to Take Loratadine

Loratadine treats allergy symptoms, both nasal and non-nasal, such as itching, sneezing, runny nose and watery eyes. It also treats itching caused by hives. However, it will not prevent a severe allergic reaction such as anaphylaxis. Loratadine can be taken as needed or on a daily basis for chronic allergies. It begins working within one to three hours, and its effects last about 24 hours.

Side Effects

Many people have no side effects with loratadine or only minor side effects. These can include (but are not limited to) headache, nosebleed, dry mouth, fatigue or drowsiness. Loratadine side effects may decrease as your body adjusts to the medicine. More serious side effects are rare, but may include nervousness, diarrhoea, stomach pain, skin rash, rapid heart rate, jaundice, feeling faint or seizure--call your doctor immediately if you experience serious side effects.

Symptoms of Loratadine Overdose

Although loratadine overdose is not likely, it is possible. Rapid heart rate, forceful heartbeat, headache and sleepiness are symptoms you may experience with doses over the recommended amount. You also may experience palpitations and extrapyramidal symptoms (tremors, twitching, restlessness). Symptoms may depend on other factors, too, such as if you took any other medications with the loratadine.

What to Do for a Loratadine Overdose

Call your doctor immediately in the event of a loratadine overdose. You also may call a poison control centre. To counteract the overdose of loratadine, you may be given ipecacuanha syrup to induce vomiting, then activated charcoal to absorb the remaining medication in your stomach, or you may need your stomach pumped. If the ingestion was not recent, you may receive symptomatic care until symptoms subside. Symptomatic care might include intravenous fluids and medication for headache, heart rate and restlessness.


Loratadine is in a class of non-sedating antihistamines; that is, it is less sedating than some other antihistamines. Care should still be taken when performing activities that require mental alertness until you know how loratadine will affect you. If you have liver or kidney disease, consult your doctor before taking loratadine. Be sure to read the package insert for full precautions and instructions for use.

Cite this Article A tool to create a citation to reference this article Cite this Article

About the Author

Based in Arizona, Kira Jaines writes health/fitness and travel articles, volunteers with Learning Ally and travels throughout the Southwest. She has more than 16 years of experience in transcribing and editing medical reports. Jaines holds a Bachelor of Arts in telecommunications and journalism from Northern Arizona University.