Latoren (Loratadine)

Loratadine acts on histamine‑mediated allergic pathways and is used for the following conditions:

• Allergic rhinitis: reduces nasal congestion, sneezing, itchy watery eyes, and post‑nasal drip, providing overall symptom control.
• Chronic urticaria: relieves hives, reduces wheal formation, and lessens associated itching for improved quality of life.
• Allergic conjunctivitis: eases eye redness, itching, tearing, and swelling of the conjunctiva during seasonal or perennial allergies.
• Hay fever: mitigates seasonal allergy symptoms such as sneezing and nasal itching.

• Loratadine selectively blocks peripheral H1 receptors, preventing histamine from binding to these sites on mast cells, smooth muscle, and vascular endothelium. By antagonizing the H1‑receptor, it inhibits the cascade that leads to vasodilation, increased vascular permeability, and sensory nerve stimulation, thereby reducing the classic signs of allergic reactions without readily crossing the blood‑brain barrier, which limits central sedation in the central nervous system.

Loratadine is generally well tolerated, but some users may experience adverse reactions.

Common Side Effects

• Headache: mild to moderate headache may occur.
• Dry mouth: sensation of reduced salivation.
• Fatigue: feeling of tiredness or low energy.
• Nausea: occasional stomach upset.
• Drowsiness: rare but possible non‑sedating effect.
• Dizziness: light‑headed sensation.
• Insomnia: difficulty sleeping.

Serious or Rare Side Effects

• Stevens‑Johnson syndrome: severe skin reaction requiring immediate medical attention.
• Angioedema: swelling of face, lips, or tongue.
• Hepatic injury: signs of liver dysfunction such as jaundice.
• Anaphylaxis: life‑threatening allergic reaction with difficulty breathing.
• Severe rash: widespread rash or blistering.

When using loratadine, consider the following precautions to ensure safe and effective therapy.

• Hypersensitivity: avoid if known allergy to loratadine or any tablet components.
• Hepatic impairment: use with caution and monitor liver function in patients with liver disease.
• Renal impairment: dose adjustment may be required for severe kidney dysfunction.
• Concomitant CNS depressants: be aware of additive drowsiness when combined with alcohol or sedatives.
• Pregnancy and lactation: safety not established; discuss risks with a healthcare professional.
• Store at ambient temperature: keep below 25 °C, protect from moisture, and retain in original packaging.

Loratadine may interact with other medicines; notable interactions are categorized below.

Major Interactions (Avoid)

• Ketoconazole: strong CYP3A4 inhibition can increase loratadine plasma levels.
• Erythromycin: macrolide antibiotic may raise loratadine concentrations.
• Ritonavir: potent CYP3A4 inhibitor may lead to heightened effects and side effects.

Moderate Interactions (Monitor Closely)

• Alcohol: may enhance drowsiness or fatigue.
• Other antihistamines: additive antiallergic effect may increase risk of sedation.
• Theophylline: possible increase in theophylline levels.
• Antidepressants (e.g., fluoxetine): may modestly affect loratadine metabolism.