As mentioned, allergies occur when the body's immune system reacts to normally harmless substances that do not bother most people. This reaction is partly caused by the release of histamine from certain cells in the body. Zyrtec blocks histamine from binding to histamine receptors and causing allergy symptoms. Since histamine is responsible for many of the symptoms of allergies, blocking it can be helpful. It is important to note that antihistamines (including Zyrtec) do not help treat nasal congestion caused by allergies, since this symptom is not due to histamine.
Older adults may need to take a lower than normal dose. Follow your doctor's instructions.
Tell your doctor if you regularly use other medicines that make you sleepy (such as other cold or allergy medicine, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety). They can add to sleepiness caused by cetirizine.
|
