Final answer:
Pharmacists must restrict access to pseudoephedrine, ask for identification, monitor purchase quantities, and offer guidance on medication use.
Step-by-step explanation:
When selling non-prescription pseudoephedrine, pharmacists must comply with regulations set by the Food and Drug Administration (FDA). Pharmacies are required to keep products containing pseudoephedrine behind the counter or in a locked cabinet to restrict access. Pharmacists must ask for identification, track sales, and limit the amount a customer can purchase. This is due to pseudoephedrine's potential use in the illegal production of methamphetamine. Furthermore, pharmacists provide guidance on the proper use of medications, including dosage, interactions, and side effects.