Acute effect of methylphenidate on QT interval duration and dispersion in children with attention deficit hyperactivity disorder

Abstract

Among childhood psychiatric disorders, attention deficit hyperactivity disorder (ADHD) is of greatest interest to practitioners. Methylphenidate (MPH) is a drug that is widely used in the treatment of children in whom ADHD has been diagnosed. Although this treatment has been used for years, its effects on the heart remain the subject of debate. The QT interval comprises the ventricular activation and recovery periods as seen on electrocardiogram (ECG). The acute effect of MPH on QT interval dispersion is unknown. Researchers in the present study sought to investigate the acute effects of MPH on QT interval as seen on ECG. A total of 25 patients with ADHD (mean age, 9.4+/-2.1 y) who were treated with MPH were enrolled in the study. Twelve-lead derivation ECGs were taken before and 2 h after administration of 10 mg of MPH. Maximum QT interval, minimum QT interval, and interval durations were measured, and QT dispersion was calculated, for each ECG. QT dispersion measured after medication administration decreased significantly from 59.6+/-16.3 ms to 50.8+/-10.9 ms (P=.016); corrected QT dispersion decreased significantly from 70.9+/-17.6 ms to 61.3+/-13.3 ms (P=.011). Maximum QT interval duration decreased from 73.7+/-21.8 ms to 361.8+/-29.0 ms (P=.006); minimum QT interval duration rose from 317.0+/-23.3 ms to 322.3+/-21.6 ms (P=.312). In conclusion, the findings of this study show that MPH reduces QT dispersion during the acute period shortly after its administration.

Dose‐Dependent Immunohistochemical and Ultrastructural Changes After Oral Methylphenidate Administration in Rat Heart Tissue

“…Evidence suggests an important role of MPH in cardiovascular system, enhancing widespread tachycardia, changes on vascular pressure and heart rate rhythm (Patrick et al., 1984). In a recent study, Ilgenli et al. (2007) also reported that MPH reduces QT dispersion during the acute period shortly after its administration.…”

“…Methylphenidate is routinely used for the treatment of ADHD (LeBlanc‐Duchin and Taukulis, 2004). Although this treatment has been used for years, its effects on the heart remain the subject of debate (Ilgenli et al., 2007). Evidence suggests an important role of MPH in cardiovascular system, enhancing widespread tachycardia, changes on vascular pressure and heart rate rhythm (Patrick et al., 1984).…”

Methylphenidate-Elicited Dopamine Increases in Ventral Striatum Are Associated with Long-Term Symptom Improvement in Adults with Attention Deficit Hyperactivity Disorder

“…Disrupted dopamine (DA) neurotransmission has been implicated in its pathophysiology (Volkow et al, 2007; Prince, 2008). The stimulants drugs methylphenidate (MP) and amphetamine are the primary medications used to treat ADHD (Ilgenli et al, 2007; Rubia et al, 2009), and both enhance DA signaling in brain (Kuczenski and Segal, 1997), which could account for their therapeutic effects. MP increases DA by blocking dopamine transporters (DATs) and amphetamine by releasing DA from the terminal using the DAT as carrier (Kuczenski and Segal, 1997).…”

Electrocardiographic effects of methylphenidate overdose

“…For example, the delayed rectifier potassium current (I Kr ) and the action potential duration were unaffected in guinea pigs, 7 and no significant methylphenidate effects on QT interval were seen in studies involving dogs 7 or humans. 8 However, one report has suggested modest increases in heart rate-corrected QT (QTc) intervals in patients prescribed methylphenidate for ADHD. 9 Because drug-induced depolarization and repolarization abnormalities are dose related, 10 it is expected that effects would be more marked in patients with drug overdose.…”