Amines in their salted form - are they stable or not?

[Pororo]

If it may look as a stupid question for you, I'm sorry, but my knowledge is limited.

Let's take any amine - amphetamine, methamphetamine or mdma their salted form. Hydrochloride for example.
Is such salt being dissolved in water stable or not?
For example, is their any evidence meth hcl is decomposited to other side substances if kept in in its liquid form with an access to the open air for a week and more?

 

[BirchGoblin]

To answer your specific question meth hydrochloride is shelf stable when dissolved in water, yes. Keep it away from direct sunlight (UV) and it'll be good for months maybe even years but who ever has had a batch of meth sitting around for that long lol

Amphetamine HCL is too hygroscopic to have a shelf life worthy of a useful pharmaceutical considering the sulfate can store just fine. It absorbs water vapor from the air and begins dissolving itself; but I'm not sure how it'd fair in wayer I don't think it would be volatile enough to evaporate or break down.

A little out of my wheelhouse but I believe MDMA is pretty much always sold as a hydrochloride and I have to imagine it would be sold as a different salt if it didn't have a very long shelf life like meth HCL

 

[Pororo]

Are you sure about meth degradation under UV? As I know meth shall be stable, but MDMA and MDA are not. They degrade under sunlight intensively, this is a fact.