The MTA study found that stimulant medication does not appear to increase the risk for abnormal elevations in blood pressure or heart rate over a 10-year period; however, the effect
of stimulants on heart rate can be detected even after years of use (Vitiello et al. 2011). The effect on heart rate may be clinically significant for individuals who have underlying heart conditions. A cohort study sought to determine whether use of MPH in adults is associated with elevated rates of serious cardiovascular events compared with rates in nonusers (Schelleman et al. 2012). All new Inhibitors,research,lifescience,medical MPH users with at least 180 days of prior enrollment were identified. Initiation of MPH was associated with a 1.8-fold increase in risk of sudden death
or ventricular arrhythmia; however, the lack of a dose response Inhibitors,research,lifescience,medical relationship suggested that this association might not be a causal one. A recent study by Habel and colleagues (Habel et al. 2011), which compared Selleckchem MEK inhibitor approximately 150,000 adults prescribed ADHD medication with approximately 300,000 nonusers, found no evidence of a link between ADHD medication and cardiovascular risk (myocardial infarction, sudden death, or stroke). Although the student enrolled adults, the same group also has reported a similar lack of significant association between serious cardiovascular events and use of ADHD medications in children and younger adults (Cooper et al. 2011). Inhibitors,research,lifescience,medical These findings support the final decision of the US Food and Drug Inhibitors,research,lifescience,medical Administration committee to not to place a black box warning for all children and adults, but to pursue further research. However, the study by Habel et al. (2011) has limitations stemming from its focus on the most severe cardiovascular event. The databases were not used to examine other cardiovascular adverse effects, such as palpitations and dyspnea, which, although
less severe, are nonetheless alarming to patients. Additional potential ADRs associated with stimulant use are important to note including abdominal pain, anorexia, constipation, dizziness, dry mouth, headache, Inhibitors,research,lifescience,medical insomnia, jitteriness, irritability, nausea, and palpitations (Greydanus and Strasburger 2006). College students with ADHD who misuse prescribed stimulants also reported hyperactivity symptoms as a common adverse event. Of particular significance to athletes, many stimulants many utilized in treating ADHD may increase core temperature (Piper et al. 2005), possibly increasing risk of heart injury. These agents may also mask signs and symptoms of fatigue and allow for a longer duration of exercise with elevated temperature in excess of 40°C. Thus, in situations of increased exogenous heat stress, stimulants should be used with caution. Conclusion Although prescription stimulants have been shown to be relatively safe and effective in managing the symptoms of ADHD, there exists a significant potential for misuse.