CASP3 and attention deficit-hyperactivity disorder: 2019). Clinical studies have reported that methylphenidate increases BDNF plasma concentrations in children with attention deficit hyperactivity disorder (ADHD) (Amiri et al. 2013). Methylphenidate can modulate apoptosis‐related proteins, including Bcl‐2 (BCL2), BAX, and caspase‐3 (CASP3) (Réus et al. 2014). Methylphenidate indirectly leads to the activation of postsynaptic dopamine receptors (Ko et al. 2019), which, upon binding dopamine, transmit the signal in postsynaptic neurons (Gronier 2011).