Mizolastine

Abstract

Mizolastine (Mizollen) is a non-sedating antihistamine. It blocks H1 receptors and is commonly fast-acting. It does not prevent the actual release of histamine from mast cells, just prevents it binding to receptors.

Medical efficacy

Mizolastine is a second generation antihistamine agent with high affinity and specificity for histamine H(1) receptors. Mizolastine has demonstrated antiallergic effects in animals and healthy volunteers and anti-inflammatory activity in animal models. Double-blind trials
have shown mizolastine to be significantly more effective than placebo and as effective as other second generation antihistamine agents, such as loratadine or cetirizine, in the management of patients with perennial or seasonal allergic rhinitis and in patients with
chronic idiopathic urticaria.
It not only has a strong anti-histamine but also has inflammatory neurotransmitters inhibit action, such as inhibit the generation of leukotrienes, reduce edema. Thus in theory, mizolastine has both anti-histamine and anti-allergic effects. The role of anti-inflammatory activity, for the treatment of acute urticaria preferred drug, significantly the onset of action is faster than other antihistamines, and the medication can reduce the number of the wheal hours after 1-3 hours, itching abated, and maintain a long time, up to 24 hours.
At present, the clinical treatment is mainly used for the treatment of adults or children over 12 years of age suffering from urticaria and other skin allergy symptoms, seasonal allergic rhinitis (hay fever) and perennial allergic rhinitis.

Precautions

Don't take this medicine in these conditions:

• If you are pregnant or breast-feeding.
• If you have any problems with the way your liver works.
• If you have a heart condition or an abnormal heart rhythm.
• If you have epilepsy.
• If you have a rare inherited blood disorder called porphyria.
• If you are taking or using any other medicines. This includes any medicines you are taking which are available to buy without a prescription, such as herbal and complementary medicines.
• If you have ever had an allergic reaction to another antihistamine, or to any other medicine.

References

http://patient.info/medicine/mizolastine-tablets-mizollen
https://en.wikipedia.org/wiki/Mizolastine
https://www.ncbi.nlm.nih.gov/pubmed/18020585

Description

Mizolastine was marketed in Germany and Switzerland as Mizollen for the symptomatic relief of seasonal and perennial allergic rhinoconjunctivitis and urticaria. Mizolastine is a new long-acting, orally active antihistaminic agent with a rapid onset of action ; the two most recent H1 antagonists launched were fexofenadine, metabolite of terfenadine (Sepracor, 1996) and Olopatadine (Kyowa Hakko, 1997). Mizolastine can be prepared in 2 steps from 2-chloro 1- (4-fluorobenzyl)benzimidazole by successive condensations of appropriate amine and thioether. Mizolastine selectively blocks the peripheral H1 receptors (but not the serotonergic, noradrenergic, muscarinic receptors) with a minimal occupancy of brain receptors, and therefore does not elicit any sedative effects. Moreover, Mizolastine does not produce cardiac rhythm disorders which have been associated with certain non-sedating antihistamines in humans.

Chemical Properties

White Solid

Originator

Synthelabo (France)

Uses

A highly selective histamine H1-receptor antagonist (with no anticholinergic, antiadrenergic, or antiserotonin activity) for use in the treatment of allergic disorders, especially rhinitis and urticaria.

Uses

Allergic rhinitis;Blocking H1 receptors

Definition

ChEBI: Mizolastine is a member of benzimidazoles.

brand name

Mizollen

Clinical Use

Antihistamine:
Symptomatic relief of allergy, e.g. hayfever, urticaria

Drug interactions

Potentially hazardous interactions with other drugs
Anti-arrhythmics: increased risk of ventricular arrhythmias - avoid with amiodarone, disopyramide, flecainide, mexiletine, procainamide and propafenone.
Antibacterials: metabolism possibly inhibited by macrolides - avoid; increased risk of ventricular arrhythmias with moxifloxacin - avoid.
Antidepressants: risk of ventricular arrhythmias with citalopram and escitalopram - avoid.
Antifungals: metabolism inhibited by itraconazole and ketoconazole and possibly imidazoles - avoid.
Antimalarials: avoid with piperaquine with artenimol.
Antivirals: concentration possibly increased by ritonavir; increased risk of ventricular arrhythmias with saquinavir - avoid.
Beta-blockers: increased risk of ventricular arrhythmias with sotalol - avoid.
Ciclosporin: use with caution due to inhibition of ciclosporin metabolism.
Cytotoxics: possible increased risk of ventricular arrhythmias with vandetanib.
Avoid concomitant treatment with any drug that could prolong QT interval.
Caution with drugs that inhibit cytochrome P450 enzymes (may elevate mizolastine levels)

Metabolism

Mainly metabolised by glucuronidation although other metabolic pathways are involved, including metabolism by the cytochrome P450 isoenzyme CYP3A4, with the formation of inactive hydroxylated metabolites