Why do amphetamines cause men to cross dress?

Answer 1

There has been no scientifically accepted study proving (or even alluding to) the idea that crossdressing relates to amphetamines. Amphetamines often do speed up the thoughts in the user and personal control (like with alcohol) is reduced, so what was already there just becomes more pronounced.

Note: if amphetamines caused crossdressing, giving crossdressers downers (barbiturates etc) would stop the crossdressing. So far no scientifically accepted study has shown any chemical way of stopping crossdressing, it has more than one root in the brain.