Zyrtec and Claritin are effective for about 24 hours. A person should only take one dose per day. The body absorbs both antihistamines quickly, but Zyrtec seems to work faster for some people.
In conclusion, cetirizine produced greater relief of seasonal allergic rhinitis symptoms than fexofenadine at 12 hours postdose and over the 5- to 12-hour postdose period.
“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.”
Sandoz issued a voluntary recall of 1,023,430 units of Zyrtec (10 mg) capsules as a result of failed impurities and a specification being reported for impurity at the 21-month stability time point, according to an FDA Enforcement Report.
What's the best time of day to take ZYRTEC®? Any time of day works. And ZYRTEC® will continue to work for 24 hours.
To sum it up, all first-generation H1 antihistamines should be taken close to bedtime or when you're able to sleep. Second-generation H1 antihistamines and H2 blockers can typically be taken at any time of the day. One exception to this is cetirizine, which can cause drowsiness for up to 14% of those who take it.
Do not use with any other antihistamines applied to the skin (such as diphenhydramine cream, ointment, spray) because increased side effects may occur. Cetirizine is very similar to hydroxyzine and levocetirizine. Do not use these medications while using cetirizine.
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.
Bottom Line. Zyrtec and Claritin are both second generation antihistamines with low risk of sedation; however, Zyrtec is more likely to cause sedation than Claritin. Zyrtec also has a quicker onset of action (one hour vs up to three hours for Claritin) but both last for 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.
The best antihistamine to take during the day to help with allergic skin rashes is Curist Allergy Relief (levocetirizine) or another antihistamine like fexofenadine or loratadine, which can provide 24-hour symptom relief without making you feel sleepy.
Allergists recommend long-acting, non-sedating antihistamines — ones that won't make you sleepy — for everyday use. Though you may know them by their brand names, the generic versions tackle the same problems: Cetirizine (Zyrtec®, Aller-Tec®, Wall-Zyr®). Fexofenadine (Allegra®, Aller-ease®, Aller-Fex®, Wal-Fex®).
Oral antihistamines, such as Zyrtec and Benadryl, shouldn't be taken together without a healthcare provider's OK. Taking oral antihistamines together can lead to additional side effects and potentially an antihistamine overdose. Signs of an overdose may include the following: Fast or racing heartbeat.
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.
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. A 5 mg product may be appropriate for less severe symptoms.
Official answer. Yes, most people can take antihistamines every day, if they have daily symptoms of their allergies.
While some over-the-counter antihistamines can cause drowsiness, routinely using them to treat insomnia isn't recommended. Antihistamines, mainly used to treat symptoms of hay fever or other allergies, can induce drowsiness by working against a chemical produced by the central nervous system (histamine).
For people who take an antihistamine such as Benadryl for a cold or allergies, drowsiness is often a welcome side effect. But a Baylor College of Medicine sleep expert cautions against turning to this type of medication as a sleep aid.
Is it safe to take Zyrtec every day? Yep. "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.
Diphenhydramine is an antihistamine medicine that relieves the symptoms of allergies. It's known as a drowsy (sedating) antihistamine and is more likely to make you feel sleepy than other antihistamines.