Common medications like Zyrtec, Allegra, Flonase, and Claritin don't usually stop working. It's time to check for new allergies if your nose is still stuffy and you can't stop sneezing after taking your regular allergy medicine. You may need a new treatment plan, not just more medication.
Relax, say the experts. 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.
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.
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.
Peak concentrations are reached within one hour of administration of Zyrtec tablets or syrup. 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 Zyrtec.
Taking more than the usual dose is unlikely to harm you or your child. If you take an extra dose, you might get some of the common side effects. If this happens or you're concerned, contact your doctor.
Adults and children 6 years and older Chew and swallow 2 tablet (10 mg) once daily; do not take more than 1 tablet (10 mg) in 24 hours.
So if, for example, cetirizine doesn't seem to help, try fexofenadine or loratadine, Hong says.
Perennial allergic rhinitis is a chronic allergic condition that causes nasal congestion and a runny nose. Unlike other types of allergies, it doesn't go away during certain seasons or months of the year. You may feel like you have a permanent cold that won't go away.
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.
Louis report that allergens in the environment often are to blame for episodes of acute itch in eczema patients, and that the itching often doesn't respond to antihistamines because the itch signals are being carried to the brain along a previously unrecognized pathway that current drugs don't target.
If antihistamines aren't giving you enough relief, it's best to see an allergist to talk about additional treatment options. They may recommend a combination of antihistamines or even prescribe other medications to manage your symptoms.
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.
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.
Allergies can cause a lot of upper respiratory symptoms, much like a cold. You may have congestion and sneezing, but you'll likely also have watery or itchy eyes and itchy skin. You may feel tired, but not necessarily feel like you're sick.
“Allergies can also cause itchy, watery eyes, which you don't normally have with a cold or flu,” Hauguel adds. Allergy symptoms usually last as long as you're exposed to the allergen, which may be about 6 weeks during pollen seasons in the spring, summer, or fall. Colds and flu rarely last beyond 2 weeks.
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.
All ZYRTEC® medicines start working at hour 1 on the first day you take it.
take 1 tablet every 12 hours; do not take more than 2 tablets in 24 hours.
“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.”
The Allegra Adult 24-Hour Allergy Relief easily tops our list thanks to the medicine's quick-acting formula to tackle your allergy symptoms any time of the day.