What is Zyrtec?
Zyrtec (cetirizine) is an antihistamine that reduces the effects of natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose.
Zyrtec is used in adults and children to treat cold or allergy symptoms such as sneezing, itching, watery eyes, or runny nose.
Zyrtec is also used to treat itching and swelling caused by chronic urticaria (hives).
Important Information
Before using Zyrtec tell your doctor about all your medical conditions or allergies, all medicines you use, and if you are pregnant or breastfeeding.
Zyrtec may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert. Drinking alcohol can increase certain side effects of cetirizine.
Tell your doctor if you regularly use other medicines that make you sleepy (such as other cold or allergy medicine, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety). They can add to sleepiness caused by Zyrtec. Call your doctor if your symptoms do not improve, if they get worse, or if you also have a fever.
Before taking this medicine
You should not use Zyrtec if you are allergic to cetirizine or levocetirizine.
Ask a doctor or pharmacist if it is safe for you to take cetirizine if you have any medical conditions.
Ask a doctor before using this medicine if you are pregnant or breastfeeding.
What happens if I miss a dose?
Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.
Zyrtec side effects
Get emergency medical help if you have signs of an allergic reaction to Zyrtec: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Stop taking this medicine and call your doctor at once if you have:
• fast, pounding, or uneven heartbeat;
• weakness, tremors (uncontrolled shaking), or sleep problems (insomnia);
• severe restless feeling, hyperactivity;
• confusion;
• problems with vision; or
• little or no urination.
Common Zyrtec side effects may include:
• drowsiness, tiredness;
• dizziness, feeling light-headed;
• feeling hot, sweating;
• numbness, tingling, burning pain;
• decreased sense of taste;
• headache;
• upset stomach, nausea, constipation; or
• dry mouth, sore throat.