Final answer:
Schedule V substances for cough and cold may include narcotics like codeine in limited quantities, though the effectiveness of such treatments, particularly in children, has been questioned.
Step-by-step explanation:
Examples of Schedule V substances include cough and cold preparations containing limited quantities of certain narcotics. Cold medicines are given to individuals with the common cold, cough, or related symptoms, and yet research has indicated that many of these do not significantly reduce cough symptoms. Specifically, codeine and guaifenesin are known to be included in some cough and cold medications, with codeine having had a historical role as a cough suppressant.
Despite its reputation, recent studies have brought into question the effectiveness of codeine in treating coughs, especially in children. In fact, it is not recommended for children due to a lack of evidence for its efficacy and potential for harm. Several other treatments, such as antihistamines and decongestants, are also common, but they should not be used empirically for chronic or unspecified coughs, especially in very young children.