Mizolastine

Indications

Mizolastine is indicated for the symptomatic relief of the following conditions:
  • Seasonal allergic rhinoconjunctivitis (hay fever)
  • Perennial allergic rhinoconjunctivitis
  • Urticaria

Pharmacology

Mizolastine, a non-sedating antihistamine, blocks histamine H1-receptors on effector cells of the GI tract, blood vessels and respiratory tract. It also has mast-cell stabilising properties.

Dosage & Administration

Adult and children above 12 years: The usual recommended dose is one 10 mg tablet daily.
Children below 12 years: Not recommended.

Interaction

Systemically administered Ketoconazole and Erythromycin, antiarrythmics e.g. Amiodarone moderately increase the plasma concentration of Mizolastine. This could increase the risk of arrythmias. Concurrent use of other potent inhibitor of the cytochrome P450 3A4 enzyme e.g. Ciclosporin should be approached with caution. No potentiation of the sedation and the alteration in performance caused by alcohol with Mizolastine has been observed.

Contraindications

Mizolastine is contra-indicated in patients with clinically significant cardiac disease or a history of symptomatic arrhythmias and in patients with known or suspected QT prolongation, patients with electrolyte imbalance (particularly hypokalaemia), and in those with clinically significant bradycardia. It is also contra-indicated in patients taking other drugs that decrease its metabolism, patients with significantly impaired liver function, and in patients who are hypersensitive to the drug.

Side Effects

Mizolastine is well tolerated in the recommended doses. The usual side effects are dry mouth, diarrhoea, abdominal pain, nausea, drowsiness, headache, dizziness, raised liver enzymes, hypotension, tachycardia and palpitations. Bronchospasm and aggravation of asthma were reported, but in view of the high frequency of asthma in the treated patient population, a causality relationship remains uncertain.

Pregnancy & Lactation

The safety of Mizolastine for use in human pregnancy has not been established. The evaluation of experimental animal studies does not indicate direct or indirect harmful effects with respect to the development of the embryo or foetus, the course of gestation and peri and post-natal development. Mizolastine should be avoided in pregnancy (particularly the 1 st trimester). Mizolastine is excreted into breast milk, therefore it is not recommended during lactation.

Precautions & Warnings

Patients should be warned that a small number of individuals may experience sedation. It is therefore advisable to determine individual response before driving or performing complicated task.

Overdose Effects

In cases of overdosage, general symptomatic surveillance with cardiac monitoring including QT interval and cardiac rhythm for at least 24 hours is recommended, along with standard measures to remove any unabsorbed drug. Studies in patients with renal insufficiency suggest that haemodialysis does not increase clearance of the drug.

Therapeutic Class

Non-sedating antihistamines

Storage Conditions

Store in a cool & dry place. Protect from light. It should be kept out of the reach of children.