Speed is the street identify for amphetamine sulphate, although it’s in some cases accustomed to check with other amphetamines. It’s usually an off-white or pinkish powder and may occasionally appear like crystals.ch?t gây nghi?n – nh?ng ch?t tác ??ng vào h? th?n kinh trung ??ng, gây bi?n ??i các ho?t ??ng ch?c n?ng c?a h? th?n kinh trun