The body absorbs both antihistamines quickly, but Zyrtec seems to work faster for some people. A study found that both drugs were absorbed into the bloodstream within 1—2 hours of taking the medication.
Researchers are often studying, comparing, and improving antihistamines. Other popular brands on the market today are Allegra and Benadryl. When a person comes into contact with an allergen, their immune system reacts and produces a chemical called histamine. Histamine causes many allergy symptoms, including inflammation of the skin or sinuses, pain, redness, and wheezing.
Immune responses also encourage extra mucus to develop, which helps to clear allergens from the nose and throat. Allergy medications block histamine responses. Claritin and Zyrtec are effective and safe for most people with minor allergies.
However, as with all medications, there may be some side effects. Loratadine—present in Claritin—may not be safe for people with severe liver conditions. The liver has to break down loratadine. The kidneys break down cetirizine—found in Zyrtec—and the body excretes it in the urine, largely unchanged. Claritin is more likely to interact with other drugs than Zyrtec. Claritin is broken down in the liver by enzymes that other drugs can inhibit. This may lead to Claritin building up in the body, which increases the risk of side effects.
Everyone reacts to medications differently, but Claritin and Zyrtec may have the following side effects:. Some people experience a severe allergic response called anaphylaxis after taking antihistamines. A person should seek emergency medical attention if any of the following symptoms are present:. Some antihistamines are safe for children, but it is a good idea to talk with a doctor or check the label carefully before giving antihistamines to a child.
In , a review found that some antihistamines may be problematic during pregnancy. However, the authors noted that there was no evidence linking cetirizine or loratidine to birth defects. A study published in noted that 10—15 percent of women use antihistamines during pregnancy.
Most appear to be safe, but some may have adverse effects. The Centers for Disease Control and Prevention CDC urge people to ask a doctor before using an antihistamine or any other drug during pregnancy. Claritin and Zyrtec are popular over-the-counter antihistamines. Doctors consider them safe and effective treatments for minor allergies. Both are second-generation antihistamines. You might need to carry two auto-injectors if there's a chance you could have a severe allergic reaction to a certain food, such as peanuts, or if you're allergic to bee or wasp venom.
A second injection is sometimes needed. As a result, it's important to call or get immediate emergency medical care. A health care professional will train you on how to use an epinephrine auto-injector. It's important to get the type that your doctor prescribes, as the method for injection may differ slightly for each brand.
Also, be sure to replace your emergency epinephrine before the expiration date. Work with your doctor to choose the most effective allergy medications and avoid problems. Even over-the-counter allergy medications have side effects, and some allergy medications can cause problems when combined with other medications.
It's especially important to talk to your doctor about taking allergy medications in the following circumstances:. Keep track of your symptoms, when you use your medications and how much you use. This will help your doctor figure out what works best. You might need to try a few medications to determine which are most effective and have the least bothersome side effects for you. There is a problem with information submitted for this request.
Sign up for free, and stay up-to-date on research advancements, health tips and current health topics, like COVID, plus expert advice on managing your health. Error Email field is required. Error Include a valid email address. To provide you with the most relevant and helpful information and to understand which information is beneficial, we may combine your e-mail and website usage information with other information we have about you.
If we combine this information with your PHI, we will treat all of that information as PHI, and will only use or disclose that information as set forth in our notice of privacy practices. You may opt-out of e-mail communications at any time by clicking on the Unsubscribe link in the e-mail. Our Housecall e-newsletter will keep you up-to-date on the latest health information. Mayo Clinic does not endorse companies or products.
Advertising revenue supports our not-for-profit mission. Any use of this site constitutes your agreement to the Terms and Conditions and Privacy Policy linked below. Mayo Clinic is a nonprofit organization and proceeds from Web advertising help support our mission. Mayo Clinic does not endorse any of the third party products and services advertised.
A single copy of these materials may be reprinted for noncommercial personal use only. This content does not have an English version. This content does not have an Arabic version. See more conditions. Allergy medications: Know your options. Products and services. Allergy medications: Know your options Several types of medications are used to treat allergy symptoms.
Here's more information. By Mayo Clinic Staff. Thank you for Subscribing Our Housecall e-newsletter will keep you up-to-date on the latest health information. Please try again. Something went wrong on our side, please try again. Show references Allergy meds could affect your driving. Food and Drug Administration. Accessed Feb. Overview of allergy and atopic disorders. Merck Manual Professional Version.
Pharmacotherapy of allergic rhinitis. AAAAI allergy and asthma drug guide. Burks AW, et al. Depending on the allergic condition being treated, the age of the person, as well as other underlying issues such as pregnancy , the best choice of antihistamine might be different. When you've been exposed to a substance you're allergic to such as pet dander, dust mite, ragweed, or peanuts , your body produces histamine , which is a chemical messenger released by cells in the immune system to alert and activate other cells and proteins of the immune system.
Histamine causes the typical allergy symptoms of sneezing, stuffy and runny nose, watery and itchy eyes, and an itchy throat that you associate with exposure to whichever allergens you are sensitive to. Antihistamines reduce the amount of histamine circulating in your system, thereby reducing symptoms.
Claritin, Zyrtec, and Allegra are all considered newer generation antihistamines. First-generation antihistamines, such as Benadryl diphenhydramine and Atarax hydroxyzine , can be helpful for allergies and hives as well, but their use is limited due to side effects such as fatigue and sedation sleepiness. So while Claritin, Zyrtec, and Allegra are all newer generation antihistamines that can treat hay fever or hives, there may be some advantages for each of these over the others.
Claritin and Zyrtec have been shown to have a good safety profile in studies of pregnant animals, but there are no human studies available. During pregnancy, they are preferred over Allegra, which has shown adverse fetal effects in animal studies. Allegra is considered to be safer for breastfeeding mothers compared to Zyrtec and Claritin. However, all three are deemed to be safe during lactation.
All three antihistamines may cause side effects such as:. That said, the side effect profile may vary slightly among them.
For instance, Allegra is completely non-sedating doesn't make people sleepy , while Claritin is minimally sedating makes only a small number of people sleepy. Zyrtec, on the other hand, causes sedation in approximately one in six people who take the medication.
While you should consult your healthcare provider about the best way to take any medication, there are widely accepted dosing recommendations for all three of these antihistamines.
First and foremost, each works best when taken daily rather than intermittently. All of these antihistamines are indicated for adults and children 2 years of age and older, with Zyrtec and Claritin dosed once a day for all ages.
Allegra is dosed twice a day for children age 2 to 11, and once a day for adults and children age 12 years and older. Finally, since Allegra can be used in children as young as 6 months of age, it's sometimes the ideal choice for young children. Besides dosing, there are some slight differences in how quickly or well the drugs work.
For example, while Claritin is effective for treating hay fever and hives, other antihistamines, such as Zyrtec and Allegra, work better and faster and last longer. Zyrtec and Allegra work quickly for the treatment of allergic rhinitis and hives, typically within less than an hour.
On the other hand, studies show that Claritin takes many hours to start working. Studies show that Allegra is nearly as good as Zyrtec at treating hayfever. However, Zyrtec and its isomer Xyzal levocetirizine appear to be better medicines for the treatment of hives. There are also some unexpected nuances associated with each of the antihistamines.
For example, if you're taking Allegra, it's important to avoid drinking fruit juice for one to two hours before you take the medication and one to two hours after. Juices such as orange juice or grapefruit juice can decrease the absorption of Allegra by nearly half. The best antihistamine choice for any one person is based on the degree of symptom relief desired and the degree of side effects you're willing to tolerate. For mild to moderate allergy symptoms, Allegra may be preferable to drugs such as Zyrtec since these other drugs are more sedating.
Yet for severe symptoms that are interfering with work, school, or play, a medication such as Zyrtec may be needed. Note that every person is different. This means that despite what studies say, there are many people who do not experience any fatigue on Zyrtec or Xyzal.
0コメント