Cetirizine hydrochloride is the active ingredient found in the allergy medication Zyrtec, which was once only available by prescription but is now available over the counter. Cetirizine is classified as an antihistamine. Antihistamines treat your seasonal allergy symptoms, like runny nose, sneezing, watery eyes and itchy throat. Generics are available at local drug and discount stores. You should always consult your pharmacist to see if generic cetirizine is appropriate for your allergies.
Uses
Product information provided by Zyrtec states that cetirizine should be used for the relief of allergic rhinitis, otherwise known as seasonal allergies, due to outdoor allergens, such as grass, ragweed and pollens. It also treats indoor allergens, like dust, animal dander and molds. Cetirizine can also reduce the severity and duration of hives and the itching associated with insect bites.
How It Works
Zyrtec, or cetirizine, is a potent H1-receptor antagonist. According to the "Delmar Nurse's Drug Handbook" by George Spratto and Adrienne Woods, H1-receptor antagonists work by telling your body not to react to allergens present in your environment. For example, if you come into contact with a substance, like cat dander, you should not have a reaction, like a runny nose or itchy eyes. If your body does identify cat dander as a threat, you produce a substance called histamine. Histamine triggers an allergic reaction, which produces symptoms like congestion, itching and sneezing. Antihistamines, like cetirizine, block the action of histamine.
Dosage
Cetirizine works at anytime, but it is most effective if taken before exposure to known allergens. A regular dosing schedule is recommended for seasonal allergy suffers.
Zyrtec is available in 5-mg or 10-mg tablets and liquid gels. Zyrtec labeling instructs patients ages 6 years to adults to take no more than 10 mg daily and notes that 5-mg tablets may be appropriate for less severe allergies. Children's Zyrtec is available, and dosage is based on the age of the child.
Product Warning
Information provided on the medication packaging states that cetirizine can cause drowsiness. So, do not operate heavy machinery or drive until you know how you react to this medication. Due to its sedating effects, you should also avoid alcohol while taking this product.
Eye Drops
Zyrtec eye drops, also available over the counter, contain cetirizine in a water solution. These drops are indicated for the relief of itchy eyes. You can use one to three drops, two times per day, in each eye to provide you with relief from your itchy eyes. You should always remove contact lenses prior to use, and keep them out for at least 10 minutes.
Zyrtec-D
Zyrtec-D contains 5 mg of cetirizine and 120 mg of pseudoephedrine. Pseudoephedrine relieves nasal and sinus congestion. Consult your physician prior to taking Zyrtec-D if you have heart disease, as pseudoephedrine can cause an increase in blood pressure. Like Zyrtec, Zyrtec-D is also available as a generic. Consult with your pharmacist to see if it is suitable for you.
References
- Zyrtec: Zyrtec for Adults
- Drugs: Cetirizine
- "Delmar Nurse's Drug Handbook"; George R. Spratto and Adrienne L. Woods; 2009
