What is zyrex syrup?

As an AI language model, I don't have access to specific details about certain brands or products. However, I can provide general information about cough syrup and its usage.

Cough syrup, also known as cough medicine, is a medication used to treat coughs and related symptoms. The main active ingredient in most cough syrups is dextromethorphan, which acts as a cough suppressant to reduce the urge to cough. Other ingredients may include antihistamines, decongestants, and expectorants, which help to loosen mucus and relieve congestion.

It's important to follow the recommended dosage and precautions on the label or as instructed by your healthcare provider. Cough syrups can interact with other medications and may cause side effects, so it's important to speak with a medical professional before taking them. Additionally, cough syrup should not be given to children under the age of four unless directed by a doctor.