What symptom indicates the use of pseudoephedrine (Sudafed) behind the counter?

The use of pseudoephedrine (Sudafed) is indicated primarily for relieving nasal congestion. This symptom arises from conditions such as allergies, colds, and sinus infections, where nasal passages become swollen and blocked due to inflammation. Pseudoephedrine works as a decongestant by constricting blood vessels in the nasal passages, leading to reduced swelling and improved airflow.

Because pseudoephedrine can be misused to manufacture methamphetamine, regulations require it to be sold behind the counter. This measure helps control the distribution of the drug while allowing those who need it for legitimate medical reasons, such as alleviating nasal congestion, to access it.

Other symptoms listed, such as acne, alopecia, and nausea and vomiting, do not relate to the primary use of pseudoephedrine. Acne and alopecia are more commonly associated with hormonal changes or other dermatological issues, while nausea and vomiting are symptoms often linked with gastrointestinal disturbances rather than respiratory conditions that pseudoephedrine is intended to treat.