United States
Hong KongPseudoephedrine limits
A regulated seller may not sell more than 3.6 grams of ephedrine, pseudoephedrine or phenylpropanolamine base to a single purchaser in one day, under 21 CFR 1314.20.
A small, precise area of the domain that generates questions because the figures are exact and easy to test.
The daily limit
No more than 3.6 grams of ephedrine base, pseudoephedrine base or phenylpropanolamine base in scheduled listed chemical products to a single purchaser in one day. 21 CFR 1314.20.
Note that the limit is expressed in grams of base, not in packages or tablets. Converting from a product to a base weight is what a harder question will ask you to do.
A package labeled with a milligram strength per tablet is describing the salt in most cases. Questions that give you tablet counts and strengths are testing whether you convert before you compare against 3.6 grams, and the careless answer is to compare the product weight directly.
What else the rules require
- Sales are recorded in a logbook, written or electronic
- The purchaser presents identification and signs
- Product is kept behind the counter or in a locked cabinet
- Sellers are trained and the seller self-certifies
Why these products are treated this way
They are listed chemicals, which means they can be used to manufacture controlled substances. The regime at 21 CFR Part 1314 is a diversion control measure rather than a clinical one.
That framing helps: the rules are about volume and identity, not about the patient's condition.
The state overlay
Several states impose stricter limits, require a prescription, or run their own tracking systems. The PTCE examines the federal position.
If your daily practice follows a stricter state rule, that is the answer to unlearn for this paper.
Common questions
What is the pseudoephedrine daily limit?
3.6 grams of base to a single purchaser in one day, under 21 CFR 1314.20.
Is the limit in grams of product?
No, grams of base. Converting from the product is what harder questions test.
What else is required at sale?
A logbook entry, identification, a signature, and product kept behind the counter or locked.
Why are these products regulated?
They are listed chemicals usable in manufacturing controlled substances, so the regime is diversion control.
Do state rules matter for the exam?
No. Several states are stricter, but the PTCE examines the federal position.