ZIRTEC ® - Cetirizine

ZIRTEC ® is a drug based on Cetirizine dihydrochloride

THERAPEUTIC GROUP: Antihistamines for systemic use - H1 antagonist

IndicationsAction mechanismStudies and clinical effectiveness Usage and dosage instructionsWarnings Pregnancy and lactationInteractionsContraindicationsUndesirable effects

Indications ZIRTEC ® - Cetirizine

ZIRTEC ® is indicated in the symptomatic treatment of allergic states and in particular in the treatment of rhinitis and allergic conjunctivitis and chronic idiopathic urticaria.

Mechanism of action ZIRTEC ® - Cetirizine

ZIRTEC ® is a drug based on Cetirizine, a piperazine derivative included among the second generation H1 antagonists, and therefore characterized by pharmacokinetic and pharmacodynamic properties such as to optimize the interaction with H1 receptors, thus limiting the occurrence of central side effects such as sedation.

Like the other antihistamines antagonists of H1 receptors, Cetirizine, even with greater affinity, after a good intestinal absorption, reaches these receptors, disseminated between the various organs and systems limiting their activation and thus manifesting:

An anti-edema action, controlling the vascular permeability at the level of the perivenular capillaries;
An anti-bronchospasmic action, controlling the activation of histamine receptors at the level of smooth muscle, responsible for bronchospasm.

Once the activity is finished and without an intense hepatic metabolism, Cetirizine, still in unchanged form, is eliminated mainly through the urine.

Studies carried out and clinical efficacy

ISTAMINERGIC PATTERN IN THE CONTROL OF NERVOUS FUNCTIONALITY

Br J Pharmacol. 2010 Sep; 16: 97-106.

A study that demonstrates that treatment with Cetirizine at 10 mg daily for two weeks can guarantee first and foremost a remission of symptoms related to chronic idiopathic urticaria in about 74% of treated patients, reaching 83% after another 2 weeks.

ADVERSE REACTIONS TO CETYRIZINE

J Am Acad Dermatol. 2004 Jun; 50 (6): 953-6.

Interesting case report that reports the occurrence of adverse skin reactions following the use of Cetirizine, demonstrating a potential cross-reactivity between this active principle and other functionally related.

Method of use and dosage

ZIRTEC ®

Cetirizine dihydrochloride 10 mg coated tablets;

Oral drops of 10 mg of Cetirizine dihydrochloride per ml of solution.

Dosage and timing of intake should be defined by your doctor based on the age of the patient, his general health conditions and the severity of the current clinical picture.

Considering the dose of 10 mg daily of Cetirizine, as the most used and effective in adults, in certain cases the doctor could consider the idea of adapting the dosages by formulating doses that respect the patient's degree of renal function.

Same thing is said for pediatric patients.

Warnings ZIRTEC ® - Cetirizine

Taking ZIRTEC ® must be preceded by a careful medical examination necessary to check the patient's overall health, as well as the specific symptoms, in order to identify conditions that are incompatible with antihistamine therapy.

Particular caution should in fact be reserved for all patients suffering from hepatic, renal, cardiac and neurological pathologies, potentially more exposed to the onset of the side effects of Cetirizine.

It is also useful to remember that the presence of hydroxybenzoates in the oral drops formulation could determine the development of hypersensitivity reactions in predisposed patients.

ZIRTEC ® tablets contain lactose, therefore its use is not recommended in patients with glucose-galactose malabsorption syndrome, lactase enzyme deficiency and hereditary galactose intolerance.

In order to obtain adequate results, it is recommended to stop taking antihistamines at least 48 hours before allergy tests.

Keep the medicine out of the reach of children.

PREGNANCY AND BREASTFEEDING

The absence of clinical trials able to verify with absolute certainty the safety of Cetirizine for the health of the unborn child and of the infant, impose the utmost caution in the use of ZIRTEC ® during pregnancy and in the subsequent period of breastfeeding.

The use of this drug in the above periods should be limited to cases of inevitable necessity and always supervised by your gynecologist.

Interactions

Patients taking ZIRTEC ® should be especially careful with alcohol and other active ingredients that can increase the risk of adverse reactions.

Contraindications ZIRTEC ® - Cetirizine

The use of ZIRTEC ® is contraindicated in case of hypersensitivity to the active ingredient or to one of its excipients or to other structurally related molecules and in patients suffering from severe liver disease and nephropathy.

Undesirable effects - Side effects

Therapy with ZIRTEC ®, especially when continued for a long time or carried out in predisposed patients, could determine the appearance of diarrhea, hypertransaminasemia, asthenia, malaise, agitation and dermatological reactions from hypersensitivity to the active ingredient or its excipients.

Fortunately, the neurological effects characterized by headache, sedation and drowsiness are such as to make driving cars or the use of machinery dangerous.