Greg Panico, a spokesman for Janssen Pharmaceutica, which is owned by Johnson and Johnson, said that the withdrawal was a voluntary business decision. “The decision to voluntarily discontinue it recognises that the allergy marketplace is crowded with a number of other drugs,” Mr Panico said.

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.

Yes. Xyzal® is safe to use every day in the evening. Use only as directed and please read the product label for complete dosing instructions and warnings.

For mild to moderate allergy symptoms, Allegra or Claritin are preferred because they are non sedating and do not make you feel sleepy. For more severe symptoms that can interfere with work, school or daily activities, Xyzal or Zyrtec may be more effective.

However, elderly patients are more likely to have age-related liver, kidney, or heart problems, which may require caution and an adjustment in the dose for patients receiving levocetirizine.

The side effects - possible anxiety, confusion, drowsiness, urine retention, dry mouth and eyes, and dizziness - make these drugs inappropriate for seniors.

Among second-generation antihistamines, Zyrtec is the strongest and most effective, says Dr. Staiger. The first-generation antihistamine Benadryl is also highly effective, but drowsiness is a limiting factor (unless you are looking to utilize it as a sleep aid), he says.

Newer antihistamines like Allegra and Claritin are generally safe for daily use. But allergy medications with decongestants, such as Claritin-D or Benadryl-D, could make your allergies worse with long-term use.

What Drugs, Substances, or Supplements Interact with Xyzal? Xyzal may interact with alcohol, other medicines that can make you drowsy (cold or allergy medicine, sedatives, narcotics, sleeping pills, muscle relaxers, medicine for seizures, depression or anxiety), ritonavir, or theophylline.

Clinically significant acute liver injury has been very rarely associated with its use. Only 2 cases of acute liver injury associated with levocetirizine have been reported in the literature. We describe the case of a 67-year-old man who developed clinically significant acute hepatic injury after using levocetirizine.

If necessary, the AAAAI recommends second- or third-generation antihistamines like cetirizine (Zyrtec), fexofenadine (Allegra), or loratadine (Claritin). But before dispensing any of these medications, check with a doctor or pharmacist to rule out any interactions with your loved one's medications.

Medications that often can be safely used by people with significant allergies include nasal corticosteroids. In addition, antihistamines such as fexofenadine (Allegra), cetirizine (Zyrtec), loratadine (Claritin) and diphenhydramine (Benadryl) are very effective.