Cetirizine hydrochloride is the active component in Zyrtec tablets and syrups. It belongs to a class called antihistamines. Antihistamines block histamine--a chemical released in response to a foreign chemical--from binding in the body. Histamine is released when chemicals called allergens are introduced into the body. This produces an allergic response. Zyrtec is indicated for seasonal and perennial, or year-round, allergies. It also has Food and Drug Administration approval for chronic idiopathic urticaria.
Treating Seasonal Allergies
Zyrtec is indicated for the treatment of season allergies in adults and children 2 and older. The common allergens include ragweed, grass and tree pollens. According to Zyrtec.com, tree pollen is one of the chief allergy offenders. Zyrtec effectively treats sneezing, runny nose, nasal congestion, watery or itchy eyes, and redness of the eyes. In children ages 2 to 5, the recommended starting dose is 2.5mg of syrup once a day. The maximum dose is 5mg of syrup or a 5mg chewable tablet once a day. The recommended starting dose in children 6 to 11 is 5mg or 10mg once a day. For adults and children older than 12, the initial dose is 5mg or 10mg.
Treating Perennial Allergies
Zyrtec is used for the relief symptoms of perennial, or year-round, allergies. Allergens that common cause of perennial allergies include dust mites, cockroaches, mold, mildew and animal dander. It may be used in adults and children older than 6 months. Symptoms of perennial allergies are the same as seasonal allergies, and Zyrtec treats them effectively. For children ages 6 months to 2 years, the recommended starting dose is 2.5mg of the syrup given once daily. The dose can be increased to no more than 5mg of syrup divided into 2.5mg every 12 hours for children 12 months to 23 months old. Recommended doses for the other age groups are the same as the doses used for seasonal allergies.
Treating Chronic Idiopathic Urticaria
Urticaria is another name for hives and is considered chronic when it persists for six months or longer. Chronic urticaria that has no known cause is said to be idiopathic. Zyrtec is indicated for the treatment of the hives and itchy lesions that form on the skin. Pfizer reports that Zyrtec significantly reduces the occurrence, severity and duration of hives, and reduces itchiness in people 6 months or older. The recommended doses for chronic idiopathic urticaria are the same as for perennial and seasonal allergies. Discuss any concerns with a health care provider.
References
- "Drug Information Handbook 15th Edition"; Charles F. Lacy, RPh, PharmD, FCSHP, Lora L. Armstrong, RPh, PharmD, BCPS. et al; 2007
- Pfizer: Zyrtec
- Zyrtec: Meet the Allergens
