Pharmacokinetic considerations about antiseizure medications in the elderly.

Large interindividual variability also due to co-morbidities and related co-therapies makes elderly patients a not homogeneous group. Overall, a reduction in loading and maintenance doses of almost all ASMs should be considered to avoid adverse events (AEs) as well as a slow titration, following the rule 'start low and go slow'. Therapeutic drug monitoring should be performed to apply the 'individual therapeutic concentration' and implemented to overcome the age-related differences between dose and plasma concentrations, to monitor DDIs and guide dosage adjustments.