Which of the following drugs is commonly associated with ephedrine in over-the-counter formulations?

Ephedrine is a stimulant often used in over-the-counter (OTC) medications, particularly those that address respiratory issues. Bronkaid is a well-known OTC formulation that includes ephedrine as one of its active components. It is specifically marketed for the temporary relief of bronchial asthma and other respiratory conditions by opening up the airways. The presence of ephedrine in Bronkaid provides a bronchodilator effect, making it an effective choice for patients seeking relief from asthma-related symptoms.

In contrast, the other options listed do not typically contain ephedrine. Advair is a prescription medication that combines a corticosteroid and a long-acting bronchodilator for chronic asthma and COPD management, making it unsuitable in this context. Singulair is a prescription medication used for allergic rhinitis and asthma but does not contain ephedrine. Flonase is also a prescription or OTC nasal spray that contains fluticasone propionate, a corticosteroid that helps reduce inflammation but lacks any association with ephedrine. Therefore, Bronkaid stands out as the correct answer due to its direct formulation containing ephedrine.