Zyrtec and Claritin have been shown to be much more effective than placebo drugs to control symptoms of rhinitis such as sneezing, runny nose, and congestion. Both drugs can also treat itching and watery eyes. Zyrtec and Claritin may also be used to treat postnasal drip from allergies as well.
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.
Most people experience at least 24 hours of relief after a single dose. Zyrtec, on the other hand, is fast acting. People who take it may feel relief in as little as one hour. Antihistamines like Zyrtec and Claritin are designed to calm the histamine reaction your body has when it's exposed to an allergen.
People who take antihistamines regularly may build up a tolerance to the drug, which means they need to take higher and higher doses to get the same effect. This can lead to addiction. Antihistamines are often addictive because they work by blocking histamine receptors.
Histamine H1 receptor antagonist cetirizine impairs working memory processing speed, but not episodic memory.
Drowsiness, tiredness, and dry mouth may occur. Stomach pain may also occur, especially in children. If any of these effects last or get worse, tell your doctor or pharmacist promptly.
Antihistamines aren't an approved treatment for anxiety that lasts more than 12 months. They're also not for use with serious psychotic or other disorders that require specialized care from a psychiatrist.
They work by blocking histamine, a natural chemical in your body. Histamine plays a role in our appetite. When antihistamines block histamine, our appetite can increase. This, plus side effects like drowsiness, could lead to weight gain.
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). These medications can be useful in certain situations, such as for treating sleeplessness related to travel.
Unrelated to the immune system, histamine is also produced in the brain, where it plays an important part in feeling awake. Antihistamines used to treat respiratory symptoms can get into the brain and interrupt this work, making you feel drowsy.
Official answer. Cetirizine can be taken at any time of the day. In most people it is non-sedating, so they take it in the morning. However, a percentage of people do find it to be sedating so if it does make you drowsy it is best to take it in the evening.
Cetirizine is the most potent antihistamine available and has been subjected to more clinical study than any other.
While most anticholinergics can be modified or monitored when taken with loratadine or cetirizine, several should be avoided entirely, including aclidinium, cimetropium, glycopyrrolate, glycopyrronium, ipratropium, oxatomide, tiotropium, and umeclidinium.
For example, some people experience symptoms with cetirizine if they take it for a while and then stop suddenly. The main withdrawal symptom is called pruritus— itching and burning sensations of the skin ranging from moderate to severe.
Antihistamines may stop working because hives can become worse over time or because the intensity of hives can wax and wane over time. It's also possible that antihistamines become less effective because people aren't taking them as prescribed.
One study also suggests cetirizine and hydroxyzine have a greater chance of causing anxiety and mood changes than other antihistamines. Hydroxyzine can also be used to treat anxiety conditions. So if you notice your symptoms worsen after starting this medication, contact your provider to discuss it further.
All ZYRTEC® medicines start working at hour 1 on the first day you take it.
Hydroxyzine's unique effect on serotonin is likely why it's the only antihistamine used for anxiety. While hydroxyzine can be used to treat many different types of anxiety disorders, it is used most often for generalized anxiety disorder (GAD), especially when it is associated with insomnia.
Cetirizine (Zyrtec, generic cetirizine) dosing information
Give once daily as needed. NOTES: 1) Dosing is based on AGE, not weight.
H1 receptor antihistamines such as cetirizine, fexofenadine, and desloratadine are among the most commonly prescribed medications for the treatment of allergies and have been shown to stimulate appetite and weight gain as side effects of treatment (6).
The side effect of sleepiness may occur when taking Zyrtec, so do not drive a car or operate potentially dangerous machinery.
Known central nervous system (CNS) adverse effects of cetirizine include anxiety, depression, insomnia, and paranoia.
Antihistamines
Impact on sleep: Using antihistamines can block the presence of an important neurotransmitter, acetylcholine , which leads to insomnia.
Take it at night in case you do feel sleepy. I never feel sleepy, but I always take it at night in case something changes (no changes in over 3 years though). The pediatric dose (5 mg) works a good 12+ hours even for an adult.
For allergy sufferers with heart disease, medicines such as Allegra, Zyrtec or Claritin should be safe. However, medicines containing decongestants — including Allegra-D, Zyrtec-D and Claritin-D — could increase your blood pressure and heart rate or interfere with your heart medication.