Does tussionex have a anthistimine in it?

Tussionex is a prescription cough syrup that contains two active ingredients: hydrocodone, an opioid cough suppressant, and chlorpheniramine, which is an antihistamine. Chlorpheniramine helps reduce allergy symptoms and can contribute to drowsiness, making it effective in treating coughs associated with colds or Allergies. Therefore, yes, Tussionex does contain an antihistamine.