The local laws are what governs. i.e in Holland most, but not all, substances are legal but in the UK they are illegal.
I agree; with certain reservations.
What riles me is that UAE are enforcing a policy which means that legal, or tolerated, intake within another sovereign country can be prosecuted within the UAE.
If you arrive in physiological possession of a UAE controlled substance and are tapped then you are in the s**t.
Their definition of 'controlled drugs' extends to Tixylix; a childrens' cough syrup!
I daren't even use Nurofen Plus if going to the UAE in the near future.
To my, RupertBear-sized mind, this is wrong.
If I decide to go to a party, country or pharmacy where a specific substance is tolerated then I should not be condemned for any inconsequential or residual amounts within my physiology or baggage when I arrive on your soil.
If I arrive 'in-country' having tangible amounts on my person or within my baggage then I should receive the full weight of the local law.
And a postscript:
It's NOT 'legal' in Holland; merely tolerated. Check your sources.