Citrizine hydrochloride, commonly known as Zyrtec, is an antihistamine that decreases histamine in the body as a treatment for allergy or hay fever symptoms (e.g., sneezing, runny nose, itchy and watery eyes). Zyrtec is used also to treat urticaria, or hives. Allergies are hypersensitive reactions of the immune system where histamines are released in response to the body's detection of antigen or potentially infectious agent. An antihistamine, then, inhibits the body's hypersensitive release of histamines, which reduces the allergy symptoms.
Common Side Effects
A few minor and common side effects of taking this medication exist, yet usually are short-lasting. These effects include drowsiness, dizziness and fatigue. Other effects that may be experienced are headaches, nausea and a dry mouth.
Moderate Effects
Zyrtec may cause effects of increasing severity. For example, one may get sunburned more easily; thus, wearing protective clothing as well as avoiding direct sun, tanning booths, etc., may be required. Also, Zyrtec is found in breast milk, so precautions are needed if one is pregnant or has recently given birth. One should not breast-feed while taking Zyrtec. Caution is needed when Zyrtec is being used by the elderly and the young, for older individuals tend to be more sensitive to the effects of this medication; and, young children may experience stomachaches and trouble sleeping if treated with Zyrtec. Also, it is recommended that one avoid alcohol while taking this medication, as it may magnify drowsiness and decrease alertness.
Serious Side Effects
Severe reactions to Zyrtec have been documented, such as breathing difficulty, chest pain or tightness and irregular heartbeat. Other major effects sometimes experienced are hives with itching, swelling of the face that may include the mouth or tongue, dizziness and fainting. Also, changes in mood or mental state may occur. In some cases, seizures, unusual bleeding and bruising have been reported, as well as jaundice and dark urine output. If any of these side effects occur, immediate medical attention is needed.
