Which of the following is an example of a cough/cold combination product?

The correct answer highlights the formulation that includes ingredients specifically targeting both cough and cold symptoms in a combined manner. The combination of dextromethorphan and promethazine is often used as a cough/cold remedy where dextromethorphan serves as a cough suppressant, helping to relieve a dry cough, while promethazine acts as an antihistamine that can alleviate allergy symptoms and promote sleep. This combination effectively addresses multiple symptoms associated with cold and cough, making it a classic example of a cough/cold product.

Other formulations presented may contain combinations of cough suppressants, antihistamines, or codeine, but they are not typically classified under the specific terms of cough/cold combination products in the same way. Brompheniramine/pseudoephedrine/dextromethorphan is indeed a multi-symptom cold medicine, but the combination is more complex and includes a decongestant. Similarly, promethazine/codeine is more focused on sedation and cough suppression, while chlorpheniramine/hydrocodone emphasizes cough relief with a narcotic component. Therefore, while these options are used for respiratory symptoms, the first choice most clearly fits the traditional definition of a cough/cold combination product.