Can amphetamine usage cause cervical dystonia?

Yes but rare: Amphetamines, such as Adderall (dextroamphetamine and racemic amphetamine) used primarily for adhd, can rarely cause cervical dystonia (also called spasmodic torticollis) all of which are fancy ways to say that you are getting an unusual degree of stiffness and muscle tightness in your neck. Some may be predisposed to have this problem and a different medication might be helpful without causing the problem. See your doctor for more help.