A child with attention deficit hyperactivity disorder (ADHD) is prescribed methylphenidate hydrochloride. What should the nurse instruct the parents regarding an adverse effect of this medication?

Choice A rationale Methylphenidate is a central nervous system stimulant and one of its common side effects is growth suppression, characterized by a slower rate of weight gain and a transient decrease in the expected rate of height increase. The mechanism is thought to be related to changes in growth hormone secretion or appetite suppression, leading to decreased calorie intake. A rapid increase in height would be an unexpected finding. Choice B rationale Decreased appetite, or anorexia, is one of the most frequently reported adverse effects of methylphenidate hydrochloride, a Schedule II CNS stimulant. The medication acts on the dopaminergic and noradrenergic systems, which can affect the satiety center in the hypothalamus, leading to a reduced drive to eat. This effect is a primary concern for the child's growth and nutritional status. Choice C rationale Garbled speech, or dysarthria, is not a typical adverse effect associated with methylphenidate. While the medication can cause anxiety or agitation, side effects are primarily cardiovascular (increased heart rate and blood pressure) and related to CNS stimulation (insomnia, nervousness, headache) or appetite suppression. Any change in speech should prompt further neurological assessment for another cause. Choice D rationale Methylphenidate is a stimulant intended to increase wakefulness and attention; therefore, sleepiness or sedation is an unlikely and contradictory side effect. A very common adverse effect of this medication is insomnia or difficulty falling asleep, especially if the last dose is given too late in the day, due to its activating properties on the central nervous system.