CNS Stimulants

Summary

CNS stimulants include drugs like amphetamine, dextroamphetamine, lisdexamfetamine, and methylphenidate. They work by increasing levels of norepinephrine and dopamine in the brain. These medications are used clinically to treat conditions like ADHD, narcolepsy, and obesity.

However, they can cause side effects such as anorexia and weight loss, nausea and vomiting, hypertension, tachycardia, insomnia, and arrhythmias. CNS stimulants also carry a high potential for abuse. To minimize sleep disturbances, CNS stimulants are typically administered in the morning at breakfast or at lunchtime, rather than later in the day.

Key Points

• Central Nervous System (CNS) Stimulants
  • Drug Names
    • Amphetamine
      • Dextroamphetamine
      • Lisdexamfetamine
    • Methylphenidate (Ritalin, Concerta)
      • Is an amphetamine-like drug, meaning it acts in a similar mechanism but has a lower potential for abuse and tolerance than amphetamines
      • Dexmethylphenidate
  • Mechanism
    • Increases dopamine and norepinephrine levels
      • Increases neurotransmitters dopamine and norepinephrine in the brain by inhibiting their reuptake
  • Clinical Use
    • Attention Deficit Hyperactivity Disorder (ADHD)
      • First line agent for treating ADHD
      • Increases attention span, decreases distractibility
    • Narcolepsy
      • Corrects abnormal sleep patterns
    • Obesity
  • Side Effects
    • Insomnia
      • These drugs stimulate the CNS, leading to alertness and arousal
      • Medication should be taken early in the day
    • Decreased appetite (anorexia)
      • Closely monitor height and weight, especially in children, since these drugs can cause growth suppression
    • Weight loss
    • Dysrhythmias
      • Use with caution in patients with cardiac disorders
    • Tachycardia
      • Report a high heart rate or palpitations to the provider
    • Hypertension
      • Related to stimulant effect of increasing norepinephrine and dopamine signaling
      • Use with caution in patients with hypertension
      • Taking with MAOIs can result in a hypertensive crisis
    • High abuse potential
      • Schedule II controlled substance
      • Dependence
        • The patient may become dependent to the medication, both physiologically and psychologically
      • Tolerance
        • The patient may become tolerant to the medication overtime, meaning a higher dose is needed to achieve the same “high”
    • Nausea/vomiting
      • Other GI side effects may also be present, such as abdominal cramping, diarrhea or constipation
  • Administration
    • Take at breakfast and lunch
      • Taking with meals (as opposed to after meals) can help ensure the patient has enough appetite to eat
      • CNS stimulants should be avoided in the evening. Generally, do not give the last dose within 4-6 hours of bedtime to prevent insomnia
    • Do not stop abruptly
      • Drug dose must be tapered down when discontinued