Some studies support the idea that ADHD in FASD is a particular clinical subtype with earlier onset, a different clinical and neuropsychologic profile, and a different response to psychostimulant medications. The Seattle Longitudinal Prospective Study suggests that infants with a history of prenatal alcohol exposure have an infant regulatory disorder and temperament disturbance which precede the diagnosis of ADHD. Research has shown that animals with prenatal alcohol exposure have an exaggerated response to psychostimulants, which is mediated by age, gender, and drug dosage. There is evidence suggesting that individuals with FASD and ADHD have a better response to dexamphetamine than methylphenidate. Patients, such as those with FASD, who have neurochemical or structural changes in the central nervous system are often hypersensitive to the effects and side effects of medication, and psychostimulant response in these patients may improve with age.6
