Fexo

Indications

Fexo 120 mg tablet containing fexofenadine hydrochloride is indicated for the relief of symptoms associated with seasonal and perennial allergic rhinitis in adults and children 12 years of age and over, including sneezing, rhinorrhea, lacrimation, itchy red eyes and itchy nose, palate or throat, and for the treatment of chronic idiopathic urticaria with itching and hives.

Pharmacology

Fexofenadine is a selective H1 histamine receptor inverse agonist. In allergic conditions exposure to an allergen causes mast cell and basophil degranulation with release of histamine and other inflammatory mediators. Histamine binds to H1 receptors and promotes further release of pro inflammatory cytokines such as interleukins, leading to pruritus, rhinorrhea and watery eyes. Fexofenadine binds to and stabilizes the inactive form of the H1 receptor, preventing activation and downstream effects. It shows potent and selective affinity for H1 receptors without clinically relevant antidopaminergic, antiserotonergic, anticholinergic, sedative or adrenergic blocking activity, and it does not significantly cross the blood brain barrier, so central nervous system effects are unlikely.

Dosage & Administration

• Allergic rhinitis, adults and children 12 years and older (tablet): 60 mg twice daily or 120 mg once daily or 180 mg once daily. In impaired renal function a starting dose of 60 mg once daily is recommended.
• Allergic rhinitis, children 6 to 11 years (tablet): 30 mg twice daily or 60 mg once daily. In impaired renal function, 30 mg once daily.
• Allergic rhinitis, children 2 to 11 years (suspension): 30 mg or 5 ml twice daily. In impaired renal function, 30 mg or 5 ml once daily.
• Chronic idiopathic urticaria, adults and children 12 years and older (tablet): 60 mg twice daily or 120 mg once daily or 180 mg once daily. In impaired renal function, 60 mg once daily.
• Chronic idiopathic urticaria, children 6 to 11 years (tablet): 30 mg twice daily or 60 mg once daily. In impaired renal function, 30 mg once daily.
• Chronic idiopathic urticaria, children 6 months to less than 2 years (suspension): 15 mg or 2.5 ml twice daily. In impaired renal function, 15 mg or 2.5 ml once daily.
• Chronic idiopathic urticaria, children 2 to 11 years (suspension): 30 mg or 5 ml twice daily. In impaired renal function, 30 mg or 5 ml once daily.

Interaction

Fexo does not undergo hepatic biotransformation and is therefore unlikely to interact with other medicinal products via hepatic metabolism. Coadministration with erythromycin or ketoconazole produces a 2 to 3 fold increase in plasma fexofenadine levels without clinically significant QT interval changes or increase in adverse reactions compared to each product alone. No meaningful interaction with omeprazole has been observed. Administration of an antacid containing aluminium and magnesium hydroxide gels 15 minutes before Fexo reduces bioavailability, probably due to binding in the gastrointestinal tract, so an interval of 2 hours is advised between Fexo and aluminium or magnesium hydroxide containing antacids.

Contraindications

Fexo is contraindicated in patients with known hypersensitivity to fexofenadine hydrochloride or to any of the excipients in the formulation.

Side Effects

In clinical trials in adults the overall incidence of adverse effects with fexofenadine was similar to placebo. Reported reactions include headache, drowsiness and dizziness affecting the nervous system, and nausea affecting the gastrointestinal system. Fatigue has been reported as an uncommon general disorder. Post marketing data describe hypersensitivity reactions with angioedema, chest tightness, dyspnoea, flushing and systemic anaphylaxis, as well as insomnia, nervousness, sleep disorders or nightmares, tachycardia and palpitations, diarrhea, rash, urticaria and pruritus. The frequency of these post marketing events cannot be estimated from available data.

Pregnancy & Lactation

There are no adequate data from the use of fexofenadine hydrochloride in pregnant women. Limited animal studies do not indicate direct or indirect harmful effects on pregnancy, embryonal or foetal development, parturition or postnatal development, but fexofenadine hydrochloride should be used in pregnancy only if clearly needed. Human data on excretion into breast milk are not available, although fexofenadine has been detected in human milk after administration of terfenadine to nursing mothers. Therefore use is not recommended during breast feeding. No human data on fertility are available, but animal studies in mice did not show an effect of fexofenadine hydrochloride on fertility.

Precautions & Warnings

Only limited clinical data are available in older people and in patients with renal or hepatic impairment, so Fexo should be used with care in these groups and dose adjustment considered in renal impairment. Patients with a history of or ongoing cardiovascular disease should be advised that antihistamines as a class have been associated with tachycardia and palpitations. Based on its pharmacodynamic profile and reported adverse reactions, Fexo is unlikely to impair the ability to drive or operate machinery and formal tests have not shown significant central nervous system effects, but individual responses should be assessed before driving or performing tasks that require full concentration.

Overdose Effects

Symptoms such as dizziness, drowsiness, fatigue and dry mouth have been reported after overdose with Fexo. Single doses up to 800 mg and multiple doses up to 690 mg twice daily for 1 month or 240 mg once daily for 1 year have been given to healthy subjects without clinically significant adverse reactions compared with placebo, and the maximum tolerated dose has not been established. Standard measures should be considered to remove any unabsorbed drug and symptomatic and supportive treatment should be provided. Haemodialysis does not effectively remove Fexo from the blood.

Storage Conditions

Store Fexo tablets in a dry place away from light and heat, in the original pack, and keep out of the reach of children.