Cough associated with the common cold may be either productive or non-productive. Cough suppressants are indicated to reduce the frequency of a cough, especially one that is dry with no production of phlegm or secretions. Cough suppressants include narcotics such as codeine as well as non-narcotics. Narcotic medications are available by prescription only and act on the cough center in the medulla and cause CNS depression. Non-narcotics suppress the nerve receptors within the respiratory tract. Common cough suppressants include codeine, dextromethorphan (Robitussin DM ™) and diphenhydramine (Benadryl™). Side effects include sedation, nausea and constipation.

Expectorants such as guiafenesin (Robitussin™) are traditionally used to help cough up sputum, although there is a lack of clinical data indicating its effectiveness. Side effects are few and include gastric upset. Terpin hydrate elixir should be avoided in the elderly due to its high alcohol content.

When choosing an over-the-counter product, the list of ingredients should be read very carefully as many preparations contain different combinations of drugs. For example, Contact™ has phenylpropanolamine, a decongestant and chlorpheniramine, an antihistamine. A person diagnosed with hyperthyroidism (overactive thyroid) and who has the common cold may not think that Contact™ is bad for him, since it is available OTC, and it has been advertised to help with itchy eyes and runny nose. However, phenylpropanolamine will stimulate his heart and make it beat faster. Warning labels are printed on the box however they are often in small print. The pharmacist should always be consulted when selecting an over-the-counter product, particularly if there are other co-existing disease states and prescription medications in use.