Cetirizine is an antihistamine medication that is used to alleviate a variety of allergy symptoms including sneezing, itching eyes/nose, hives, runny nose, watery eyes, and itching.
This medication exerts its effects by inhibiting the activity of histamine, a natural substance produced by the body during an allergic reaction. Cetirizine is not intended to prevent the occurrence of hives or treat severe allergic reactions, such as anaphylaxis. Cetirizine should not be used as a substitute for epinephrine.
Uses and Dosage
If you intend to self-treat with an over-the-counter product, carefully read all directions provided on the product package prior to taking the medication. If you have any questions or concerns, seek guidance from your pharmacist.
If your physician has prescribed this medication, take it precisely as directed, usually once per day.
If you are using chewable tablets, ensure that you thoroughly chew each tablet before swallowing. If you are using the rapidly-dissolving tablet, place it on your tongue and allow it to dissolve before swallowing, with or without water. If the liquid form of this medication is prescribed, measure the dose accurately using a specialized measuring device/spoon, rather than a common household spoon, to ensure you receive the appropriate dose.
The appropriate dosage of this medication is determined by several factors, including your age, medical condition, and response to treatment. Do not exceed the recommended dose or take this medication more frequently than directed.
If your allergy symptoms do not improve, if your hives do not resolve after three days of treatment, or if your hives persist for longer than six weeks, inform your doctor.
Seek immediate medical attention if your condition worsens, or if you suspect that you are experiencing a severe medical problem, such as a serious allergic reaction or anaphylaxis.
Some side effects may occur that usually do not need medical attention:
- dry mouth
- loss of appetite
- sore throat
Inform your healthcare provider immediately if you experience any serious side effects:
- allergic reactions like skin rash or hives, swelling of the face, lips, or tongue
- breathing problems
- changes in vision
- eye pain
- fast, irregular heartbeat
- high blood pressure
- trouble passing urine or change in the amount of urine
- trouble sleeping
- unusually weak or tired
Prior to initiating treatment with cetirizine, inform your doctor or pharmacist of any allergies you may have, particularly if you are allergic to cetirizine, hydroxyzine, levocetirizine, or any other substances. This product may contain inactive ingredients that could cause allergic reactions or other complications.
Before using this medication, disclose your medical history to your physician or pharmacist, particularly if you have a history of difficulty urinating, such as due to an enlarged prostate, kidney disease, or liver disease.
If you are utilizing this medication to treat hives, inform your doctor immediately if you develop any of the following symptoms, as they may be indicative of a more serious condition: hives that have an unusual color, hives that appear bruised or blistered, or hives that are not accompanied by itching.
This medication may cause drowsiness. The use of alcohol or marijuana may increase drowsiness. Avoid activities that require alertness, such as operating machinery or driving, until you can perform them safely.
Liquid forms of cetirizine may contain sugar. If you have diabetes, use caution when using this product.
During pregnancy, this medication should only be administered if it is clearly required. Discuss the benefits and risks with your doctor.
This medication passes into breast milk. Consult your doctor prior to breastfeeding.
Form and Strength
Zyrtec is available in the following forms and strengths:
How long does it take for Zyrtec to work?
The onset of effect occurs within 20 minutes in 50% of people and within an hour in 95%. Effects persist for at least 24 hours following a single dose of cetirizine.
Can I use Zyrtec only when I need it?
Yes, you can take Zyrtec only when you need it if you have allergy symptoms once in a while. But if you have allergy symptoms on a daily basis, taking it regularly according to the manufacturer’s directions might give you the most relief from your allergies.