In the UK ‘Sudafed’ (the brand of decongestants) is available off the shelf, but doesn’t contain pseudoephedrine. There is a different ‘Sudafed’ branded coloured box that you can get from behind the counter by asking someone, that does contain pseudoephedrine.
It's more due to the fact that you can only buy it in tiny amounts "because some people use it to make meth." As far as I know, that restriction predated the show by several years at least.