Yes, you can take cetirizine (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.
"When taken in the recommended doses, antihistamines can be taken daily. This is especially true with Zyrtec, since it doesn't show decreasing effectiveness if used daily," says Sima Patel, MD, an allergist at New York Allergy & Sinus Centers.
They work quickly to help get symptoms under control. But if taken every day, they can also help prevent symptoms from starting.
When an allergy medication doesn't work anymore—either as well as before or at all—it could be because your body is no longer reacting to the drug in the same way it once did or is clearing it too quickly for it to be effective. This is known as a drug tolerance. This can happen after months and years of use.
Cetirizine reaches peak plasma concentration after approximately one hour. Its effects typically begin after 20 to 60 minutes and persist for at least 24 hours. Food does not affect the extent of exposure (AUC) of cetirizine, but the time to attain peak concentration is delayed by 1.7 hours.
ZYRTEC 10 mg film-coated tablets
The maximum recommended daily dose is 20 mg, do not exceed this dose, unless told to do so by your doctor.
Is it okay to take ZYRTEC® over a long period of time? The ZYRTEC® package label doesn't state a limit on how long you can take ZYRTEC®. Talk to your doctor if you have any questions, especially if you're taking other medicines or being treated for any other conditions.
If you have seasonal allergies and notice that your allergy medicine stops working, it might be because you've developed new allergies. People rarely develop a tolerance to allergy medications. Common medications like Zyrtec, Allegra, Flonase, and Claritin don't usually stop working.
Why do antihistamines stop working? Antihistamines can stop working because your allergies might be getting worse or you might have immune system changes due to aging. You also might not be taking the medication as directed. If you take an antihistamine after being exposed to an allergy trigger, it won't work as well.
It's not a great idea, but an isolated incident of taking two Zyrtec is unlikely to have major health effects. In fact, some doctors double the dose of Zyrtec for their patients with severe hives if a single pill isn't working.
Some medications for treating allergies, like Zyrtec (cetirizine) and Allegra (fexofenadine) last 24 hours and don't need to be taken at night. But if you're combating allergy symptoms with a different antihistamine first thing in the morning, keep in mind that its effects will only last six to eight hours.
Taking too much antihistamine can lead to adverse side effects and a potential antihistamine overdose. Antihistamines are a class of medication that treat allergy symptoms, such as sneezing, runny nose, and itching. As with any medication, taking too much can be harmful.
Commonly used first-generation antihistamines have strong anticholinergic properties, and recently published data from the adult population have suggested that long-term use of these drugs may increase the risk for developing dementia.
Zyrtec (cetirizine) is the strongest of the second-generation antihistamines, says Dr. Garcia-Ibáñez. And because there is less chance of toxicity with this medication, the dosage can be increased substantially, at the discretion of your doctor, he says. Zyrtec is an effective treatment for allergy symptoms and hives.
take 1 tablet every 12 hours; do not take more than 2 tablets in 24 hours.
Since both medications have a common core chemical structure, Zyrtec and Xyzal generally have the same level of effectiveness, onset of action, and range of allergy symptoms treated. Xyzal is slightly less drowsy, so if drowsiness is an issue with your allergy medicine, Xyzal is better than Zyrtec.
When a person stops taking their medication, their body will produce more histamine to make up for the lack of antihistamine. This results in extreme itching. It's common for someone who's addicted to an antihistamine to scratch until they're raw and bleeding.
Cetirizine is unlikely to do you any harm if you take it for a long time. However it's best to take cetirizine only for as long as you need to. If you take it regularly over a long period there's a very small chance of severe itching if you stop treatment suddenly.
Rarely, they can cause acute self-limited liver injury. One study has reported a more serious long-term effect, a 3.5-fold increase in the risk of gliomas, a common type of brain tumor in patients with long-term antihistamine use for allergic conditions.
ZYRTEC® Allergy Relief Tablets
Adults under 65 and children 6 years and older One 10 mg tablet once daily; do not take more than one 10 mg tablet in 24 hours.
by Drugs.com
This is a therapeutic duplication and it is usually recommended to take only one antihistamine at any time, however if you have been prescribed to take both together then it is appropriate. If you do experience any odd symptoms please see your doctor.
“Zyrtec is found to be more potent, or stronger, in laboratory studies, compared with Claritin,” says Dr. Kung. “It also reaches a higher concentration in the skin, which can be more helpful for skin-related allergies. However, Zyrtec has a greater chance of making you sleepy while taking it.”
Official answer. Yes, most people can take antihistamines every day, if they have daily symptoms of their allergies. The number of times you take an antihistamine each day depends on the type of antihistamine.
Newer antihistamines like Allegra and Claritin are generally safe for daily use. But allergy medications with decongestants, such as Claritin-D or Benadryl-D, could make your allergies worse with long-term use.