Wek 10 - Chapter 36 Central Nervous System Stimulants and Attention-Deficit/Hyperactivity Disorder

Question 1

Amphetamines

Answer 1

The amphetamine family consists of amphetamine, dextroamphetamine, methamphetamine, and lisdexamfetamine. All are powerful CNS stimulants. In addition to their CNS actions, amphetamines have significant peripheral actions—actions that can cause cardiac stimulation and vasoconstriction. The amphetamines have a high potential for abuse.

Question 2

ADHD

Answer 2

ADHD is the most common neuropsychiatric disorder of childhood, affecting 5% of school-age children. The incidence in boys is 2 to 3 times the incidence in girls. Symptoms begin between ages 3 and 7, usually persist into the teens, and often persist on into adulthood. The majority (60% to 70%) of children respond well to stimulant drugs.
In about 30% to 60% of cases, childhood ADHD persists into adulthood. In the United States, about 8 million adults are afflicted, although an estimated 90% are undiagnosed and untreated. Symptoms include poor concentration, stress intolerance, antisocial behavior, outbursts of anger, and inability to maintain a routine. Also, adults with ADHD experience more job loss, divorce, and driving accidents. As in childhood ADHD, therapy with a stimulant drug is the foundation of treatment. Methylphenidate is prescribed most often. About 33% of adults fail to respond to stimulants or cannot tolerate their side effects. For these patients, a trial with a nonstimulant may help. Combining behavioral therapy with drug therapy may be more effective than drug therapy alone.

Question 3

Methylxanthines

Answer 3

methylated derivatives of xanthine, hence the family name. These compounds consist of a xanthine nucleus with one or more methyl groups attached. Caffeine, the most familiar member of the family

Question 4

Amphetamine Sulfate -category

Answer 4

Amphetamine

Question 5

Methylphenidate -category

Answer 5

CNS stimulant

Question 6

Caffeine - category

Answer 6

Methylxanthine

Question 7

Atomoxetine - category

Answer 7

Norepinephrine Uptake Inhibitor

Question 8

Amphetamine Sulfate - use

Answer 8

prominent effects on mood and arousal. At usual doses, they increase wakefulness and alertness, reduce fatigue, elevate mood, and augment self-confidence and initiative. Euphoria, talkativeness, and increased motor activity are likely. Task performance that had been reduced by fatigue or boredom improves

Question 9

Amphetamine Sulfate - adverse effects

Answer 9

insomnia, restlessness, weight loss, increase of heart rate and blood pressure, paranoid psychosis.

Question 10

Amphetamine Sulfate - mechanism of action

Answer 10

release of norepinephrine (NE) and dopamine (DA), and partly by inhibiting reuptake of both transmitters. These actions take place in the CNS and in peripheral nerves. Most pharmacologic effects result from release of NE.

Question 11

Methylphenidate - use

Answer 11

ADHD and narcolepsy

Question 12

Methylphenidate - adverse effects

Answer 12

insomnia, reduced appetite, emotional lability, abuse liability

Question 13

Methylphenidate - mechanism of action

Answer 13

promotion of NE and DA release, and inhibition of NE and DA reuptake

Question 14

caffeine - use

Answer 14

stimulant effects: neonatal apnea, promote wakefulness, etc

Question 15

caffeine - mechanism of action

Answer 15

(1) reversible blockade of adenosine receptors, (2) enhancement of calcium permeability in the sarcoplasmic reticulum, and (3) inhibition of cyclic nucleotide phosphodiesterase, resulting in accumulation of cyclic adenosine monophosphate (cyclic AMP). Blockade of adenosine receptors appears responsible for most effects.

Question 16

caffeine - adverse effect

Answer 16

potential birth defects, dysrhythmias of the heart

Question 17

Atomoxetine - use

Answer 17

nonstimulant approved for ADHD

Question 18

Atomoxetine - adverse effects

Answer 18

a selective inhibitor of NE reuptake, and hence causes NE to accumulate at synapses. Although the precise relationship between this neurochemical action and symptom relief is unknown, it would appear that adaptive changes that occur following uptake blockade underlie benefits. Uptake blockade occurs immediately, whereas full therapeutic effects are not seen for at least a week—suggesting that, after uptake blockade occurs, additional processes must take place before benefits can be seen.

Question 19

Atomoxetine - mechanism of action

Answer 19

generally well tolerated. In clinical trials, the most common effects were GI reactions (dyspepsia, nausea, and vomiting), reduced appetite, dizziness, somnolence, mood swings, and trouble sleeping. Sexual dysfunction and urinary retention were seen in adults. Severe allergic reactions, including angioneurotic edema, occurred rarely. If allergy develops, patients should discontinue the drug and contact their prescriber immediately.