Can I bring prescription Adderall into Vietnam while on vacation there?

This thread from four years ago asks What are Vietnamese laws on prescription drugs like adderall or ritalin? Is it available, how does one go about getting a prescription. Responses there include No prescriptions needed, but some western/imported/quality drugs you might have a difficult time finding. and From what I understand you cannot get any of the ADD/ADHD medications I.E. Adderall, Ritalin, Concerta. The doctors at the "international" clinics and hospitals will give you a prescription for it, but no pharmacies actually carry the medication.

So at this point the issue is availability rather than legality. (In 2004 for example it was reported as legal to bring Adderrall into Mexico though the drug was not on sale there.)

What you may have heard might be along the lines of another post in the same thread (if that was actually your source, it would have helped to say so):

According to a famous (for drinking, mostly) child psychologist I know, in Vietnam the amphetamine-based ADHD medications are on a ban list that more or less puts them on a par with narcotics. This psych was trying to help the parents of a needy young patient source dexamphetamine, but after jumping through the standard medical hoops you'd expect to face back home, discovered the above fact. Which means that it's simply not available - not from hospitals, western clinics or even dodgy pharmacies that might be willing to sell you other medication that you definitely can't buy over the counter back home. So, regardless of whether you have a prescription or not, you can't get Adderall etc here through legal or even grey channels. It's pretty much illegal and will have to be obtained outside of Vietnam, unfortunately.

That mentions a ban list but rather loses impact when ending will have to be obtained outside of Vietnam.

For less indirect experience also in the thread is:

Last time I went home I had to do my best to stockpile what I could.

I believe a problem here is as described in a report by Pacific Bridge Medical, admittedly dated July 1, 2005:

Pharmaceutical and drug registration is regulated by the MOH in Vietnam, though the regulatory environment can often be unclear and inconsistent. Regulations are frequently implemented on a case-by-case basis, with little overall coordination. Partially-regulated situations, or regulations that are clearly contradictory, are not unheard of. Moreover, it can be difficult to determine what is permitted in Vietnam and what is illegal.

(eg Marijuana is illegal in Vietnam, as well as most other social vices. The penalties in the books are very strict, however the police seems to look the other way or will ask for a small negotiable bribe. From webehigh.org).

and

The definition of “pharmaceutical products” is somewhat ambiguous under Vietnamese law. The MOH only states that pharmaceutical products are products intended for human consumption for the purpose of prevention, treatment, relief or diagnosis of diseases, or for the modification of physiological functions. Any pharmaceutical products manufactured, sold or distributed in Vietnam must first be registered with the MOH.

It would appear that Adderall has not been, but I have no idea whether somebody has: tried and failed, not bothered to try, or known better than to try.

More reliable in my view Is information from 30/3/2016, though a response to an enquiry about shipping Adderall in advance of a visit to Vietnam, in order to avoid problems at a Japanese layover, rather than for direct personal import by a visitor. From Vietnam Customs:

Medicines on the personal luggage of exit and entry submitted under the bill of lading, cargo and personal effects of the exit and entry are called non-commercial imported medicines.
- Non-commercial imported or exported medicines shall be used only for personal or family disease treatment, not be sold or used for any illegal proposes.
-Non-commercial imported or exported medicines must bear labels indicating appellations of medicines, appellations of active substances, concentration, content, and use duration.
* Medicines banned from non- commercial import or export
- Medicine materials
- Medicines containing active substances on the list of active substances banned from non-commercial import or export provisions of Circular 47/2010/TT-BYT dated 21/12/2010 by the Minister of Health and other documents.

You can refer Medicines containing active substances on the list of active substances banned from non-commercial import or export provisions of Circular 47/2010/TT-BYT dated 21/12/2010, to see "Adderall" is of the prohibited drug list or not. If not in this list, you can bring into Vietnam if they meet the following conditions:
* Procedure for non-commercial imported medicines:
a / Prescription in English or Vietnamese language made up by a foreign physician. If in other languages must be translated into English or Vietnamese language and must have the following contents:
- Name and age of the patient;
- Appellation of the medicine, its content or concentration and volume;
- Quantity of the medicine (or the number of days for medicine use);
- Dosage;
- Full name and signature of the physician;
- Address of the physician (address of the physician’s practice place: hospital, clinic, etc.).

So does Adderall feature on the Circular 47/2010/TT-BYT dated 21/12/2010? Unfortunately, that reference seems out of date and should perhaps have been 44/2014/TT-BYT of 25/11/14 where I suspect the appendices (in Vietnamese - TT44_25112014BYT.pdf) will show whether or not Adderall is listed.

I tend to feel that (i) if Vietnam cared it would be less circumspect with the relevant details and (ii) in this case "Can I" may be unanswerable (eg contradictory legislation is not 'law').

You might try to find out what is in whichever of the circulars is relevant but it may not be easy and there may not be much point anyway. However I would heed ibr04694 from TripAdvisor 23 February 2011, 05:55 re travelling with ADHD medication (for a child):

The international protocol for travelling with medicines is that: They be in original packaging. They be labelled with the dispensers/dispensary name. And labelling shows the name of the person (your son) for whom the medicine has been prescribed. Although not technically essential, it is prudent for the original prescription or a copy of it to be held by any accompanying parent/adult or supervisor. You will have no problems about this. No need to even mention it.

Since not an Answer should have been a Comment but too long for that.