Complete adverse effect profile including incidence rates and management
Important Safety Information
This is not a complete list of all possible side effects. Contact your healthcare provider if you experience any unexpected symptoms. For serious or life-threatening side effects, seek emergency medical attention immediately.
Headache (12% in adults, most commonly reported side effect)
Somnolence/drowsiness (8%; significantly less than first-generation antihistamines but can occur)
Fatigue (4%)
Dry mouth (xerostomia, 3%)
Nervousness (4%, particularly in children)
Nausea (2-3%)
Pharyngitis/sore throat (3%)
Abdominal pain (2%, more common in pediatric patients)
Increased appetite (1-2%)
Epistaxis/nosebleed (2-3% in pediatric patients)
Diarrhea (2%)
Rash (2%)
Urticaria/hives (paradoxical, <1-2%)
Dizziness (1-2%)
Blurred vision (1-2%)
Hypersensitivity reactions including anaphylaxis, angioedema, urticaria, and bronchospasm — discontinue immediately and seek emergency care
Severe hepatic dysfunction: loratadine is extensively metabolized by the liver; severe hepatic impairment can lead to markedly elevated plasma concentrations and toxicity
QT prolongation: rare but reported, particularly with drug interactions involving CYP3A4 or CYP2D6 inhibitors that increase loratadine plasma levels
Paradoxical CNS stimulation: especially in young children, may present as irritability, insomnia, agitation, or tremor
Seizures: rare case reports, mechanism unclear; use with caution in patients with known seizure disorders
Urinary retention: anticholinergic effect, more common in males with benign prostatic hyperplasia (BPH)
Palpitations and tachycardia: particularly with Claritin-D formulations containing pseudoephedrine
Hepatotoxicity: rare case reports of elevated liver enzymes and jaundice; monitor liver function in at-risk patients
Alopecia (hair loss): rare post-marketing reports
Erythema multiforme: rare severe skin reaction requiring immediate discontinuation
Fixed drug eruption: localized skin reaction at the same site on re-exposure
Thrombocytopenia: rare hematologic effect; monitor in susceptible patients
Photosensitivity reaction: increased sensitivity to sunlight reported rarely
Dysgeusia (altered taste perception): rare report in post-marketing surveillance
Breast enlargement (gynecomastia): extremely rare, mechanism uncertain
Supraventricular tachyarrhythmias: rare, associated with high plasma levels from drug interactions
Like all medications, Claritin can cause side effects. However, not everyone who takes this medication will experience them. Many side effects are dose-dependent and may improve as your body adjusts to the medication. Others may require dose adjustment or medical attention.
Contact your healthcare provider promptly if you experience:
Seek immediate emergency medical care if you experience signs of: