ADHD medications don't cause tics, exactly.

Studies have shown that these medications carry a lower risk than the older drugs of tardive dyskinesia, a disorder that causes tics, lip-smacking and other involuntary movements.

According to Roger Freeman, MD, "Genes that cause tics have not yet been identified; it's very unlikely there's just one.

Other perinatal events, such as maternal stress, maternal smoking, and obstetric complications, while not causing tics, may be risk factors for increased severity of tics.

Tourette syndrome is a neurological disorder that causes physical and vocal tics.

All these drugs are known as atypical antipsychotics, to distinguish them from an earlier class of antipsychotic medications that can cause tics and sometimes even disfigurement.

Mr. Davis has Tourette's syndrome, a neurological disorder that causes involuntary motor and vocal tics.

The disease causes vocal and physical tics, and Eisenreich said he still gets teased by fans.

Jaylen has Tourette syndrome, a condition that causes tics - sudden, repetitive physical movements or verbal outbursts.

The medicines may cause side effects such as loss of appetite, headaches or stomachaches, tics or twitches, and problems sleeping.