Common Side Effects of Claritin
Claritin (loratadine), an over-the-counter antihistamine for allergies, causes side effects in less than 10% of users. The most frequent include headache, drowsiness (mild compared to older antihistamines), fatigue, and dry mouth. Stomach pain, vomiting, or nervousness occur less often.[1][2]
Serious or Rare Side Effects
Severe reactions are uncommon but include fast heartbeat, allergic responses like rash, itching, swelling (face/tongue/throat), or trouble breathing—seek emergency care immediately. Rare cases report seizures, yellowing skin/eyes (liver issues), or severe dizziness.[1][3]
Side Effects in Children vs. Adults
Kids on Claritin RediTabs or syrup (ages 2+) may experience similar effects but more often hyperactivity, stomach upset, or wheezing. Adults report higher rates of headache (12%) and somnolence (8%). Use caution in children under 6 without doctor approval.[2][4]
What Happens If You Overdose
Overdose symptoms include headache, rapid heartbeat, drowsiness, or seizures. Typical adult dose is 10 mg daily; exceeding it risks heart rhythm changes. Call poison control or 911; no specific antidote exists—treatment is supportive.[1][3]
Drug Interactions and Who Should Avoid It
Claritin interacts with ketoconazole, erythromycin (raises blood levels), or alcohol (increases drowsiness). Avoid if you have liver/kidney issues, phenylketonuria (from RediTabs), or are pregnant/breastfeeding without advice. Not for glaucoma or enlarged prostate.[2][4]
How Long Do Side Effects Last
Most resolve within hours to a day as the drug clears (half-life 8 hours). Persistent effects like headache may linger 1-2 days. Drowsiness is minimal and short-lived versus Benadryl.[1][3]
[1]: FDA Claritin Label
[2]: Mayo Clinic - Loratadine
[3]: Drugs.com - Claritin Side Effects
[4]: WebMD - Claritin