Efletirizine

Efletirizine is a second-generation antihistamine used primarily for the treatment of allergic rhinitis and chronic urticaria. It is known for its selective antagonism of the H1 receptor, which helps alleviate symptoms associated with histamine release, such as sneezing, itching, and runny nose.

Pharmacology

Efletirizine is a piperazine derivative that exhibits high affinity for the H1 receptor, thereby inhibiting the action of histamine, a compound involved in allergic responses. Unlike first-generation antihistamines, efletirizine is less likely to cross the blood-brain barrier, reducing the risk of sedation and other central nervous system effects.

Mechanism of Action

Efletirizine works by competitively binding to the H1 receptor sites on effector cells in the gastrointestinal tract, blood vessels, and respiratory tract. This prevents histamine from exerting its effects, which include vasodilation, increased vascular permeability, and sensory nerve stimulation.

Pharmacokinetics

Efletirizine is well absorbed after oral administration, with peak plasma concentrations occurring within 1 to 2 hours. It is metabolized in the liver and excreted primarily in the urine. The half-life of efletirizine is approximately 8 to 10 hours, allowing for once-daily dosing.

Clinical Use

Efletirizine is indicated for the relief of symptoms associated with seasonal and perennial allergic rhinitis, such as nasal congestion, sneezing, and itching. It is also effective in managing symptoms of chronic idiopathic urticaria, providing relief from hives and itching.

Adverse Effects

Common side effects of efletirizine include headache, dry mouth, and fatigue. Rarely, it may cause dizziness or gastrointestinal disturbances. Due to its low sedative profile, it is generally well-tolerated compared to first-generation antihistamines.

Contraindications

Efletirizine is contraindicated in patients with known hypersensitivity to the drug or any of its components. Caution is advised in patients with severe renal impairment, as dosage adjustments may be necessary.

Interactions

Efletirizine may interact with other central nervous system depressants, enhancing their sedative effects. It is also advised to avoid concurrent use with alcohol, as it may potentiate drowsiness.

Also see

• Antihistamine
• Allergic rhinitis
• Chronic urticaria
• Histamine
• H1 receptor antagonist