Chapter 13 Central Nervous System Stimulants and Related Drugs

Question 1

CNS Stimulants

Answer 1

• Drugs that stimulate a specific area of the brain or spinal cord
• Neurons contain receptors for excitatory neurotransmitters, including dopamine (dopaminergic drugs), norepinephrine (adrenergic drugs), and serotonin (serotonergic drugs)
• Sympathomimetic drugs

Question 2

Major therapeutic uses of CNS Stimulants

Answer 2

anti–attention deficit disorder, antinarcoleptic, anorexiant, antimigraine, and analeptic drugs

Question 3

Attention Deficit Hyperactivity Disorder (ADHD)

Answer 3

• Most common psychiatric disorder in children, affecting 4% to 10% of school-age children
• Boys are affected from two to nine times more often than girls.
• Drug therapy for both childhood and adult ADHD is the same.

Question 4

Narcolepsy

Answer 4

Incurable neurologic condition in which patients unexpectedly fall asleep in the middle of normal daily activities. These “sleep attacks” are reported to cause car accidents or near-misses in 70% or more of patients.

Question 5

Cataplexy

Answer 5

sudden acute skeletal muscle weakness. Associated symptom in at least 70% of narcolepsy cases. It involves sudden acute skeletal muscle weakness.

Question 6

Analeptic-Responsive Respiratory Depression Syndromes

Answer 6

• Neonatal apnea
• Bronchopulmonary dysplasia
• Postanesthetic respiratory depression
• Drugs: analeptic drugs such as theophylline, aminophylline, caffeine, and doxapram

Question 7

Drugs for Attention Deficit Hyperactivity Disorder (ADHD) and Narcolepsy

Answer 7

-Amphetamines: methylphenidate
-Nonamphetamine stimulants
Pemoline and Modafinil
Atomoxetine: nonstimulant drug that is also used to treat ADHD
Lisdexamfetamine (Vyvanse) prodrug for dextroamphetamine

Question 8

Amphetamines

Answer 8

Stimulate areas of the brain associated with mental alertness

Question 9

CNS effects

Answer 9

• Mood elevation or euphoria
• Increased mental alertness and capacity for work
• Decreased fatigue and drowsiness
• Prolonged wakefulness

Question 10

Respiratory effects

Answer 10

• Relaxation of bronchial smooth muscle
• Increased respiration
• Dilation of pulmonary arteries

Question 11

Adverse Effects of Stimulants

Answer 11

-Wide range; dose related
-Tend to “speed up” body systems
-Common adverse effects include:
Palpitations, tachycardia, hypertension, angina, dysrhythmias, nervousness, restlessness, anxiety, insomnia, nausea, vomiting, diarrhea, dry mouth, increased urinary frequency, others

Question 12

Principal Drugs Used to Treat ADHD and Narcolepsy

Answer 12

• Amphetamines
• Nonamphetamine stimulants
• Atomoxetine: nonstimulant drug also used for ADHD

Question 13

Atomoxetine (Strattera)

Answer 13

• Approved for treating ADHD in children older than 6 years of age and in adults
• In September 2005, the FDA issued a warning describing cases of suicidal thinking and behavior in small numbers of adolescent patients receiving this medication.

Question 14

Methylphenidate (Ritalin)

Answer 14

-First prescription drug indicated for ADHD
-Also used for narcolepsy
-Extended-release dosage forms
Ritalin SR
Concerta
Metadate CD

Question 15

Modafinil (Provigil)

Answer 15

• Use: improvement of wakefulness in patients with excessive daytime sleepiness associated with narcolepsy and with shift work sleep disorder
• Less abuse potential than amphetamines and methylphenidate
• Schedule IV drug
• Armodafinil (Nuvigil): similar to modafinil

Question 16

Anorexiants

Answer 16

-Used to treat obesity
-Anorexiants
phentermine (Ionamin)
benzphetamine (Didrex)
methamphetamine (Desoxyn)
diethylpropion (Tenuate)

Question 17

Orlistat (Xenical)

Answer 17

-related nonstimulant drug used to treat obesity
Mechanism of action: works locally in the small and large intestines, where it inhibits absorption of caloric intake from fatty foods.

Question 18

Mechanism of Action for Obesity Drugs

Answer 18

• Suppress appetite control centers in the brain
• Increase the body’s basal metabolic rate
• Mobilization of adipose tissue stores
• Enhanced cellular glucose uptake
• Reduce dietary fat absorption

Question 19

Adverse effects of obesity drugs

Answer 19

• Possible elevated blood pressure and heart palpitations
• Anxiety
• Agitation
• Dizziness
• Headache

Question 20

Antimigraine Drugs

Answer 20

Antimigraine (serotonin agonists; also called triptans)

Question 21

Ergot alkaloids

Answer 21

• Were the mainstay of treatment of migraine headaches but have been replaced by the triptans for first-line therapy
• Dihydroergotamine mesylate (D.H.E. 45): injectable form and as a nasal spray (Migranal)
• Ergotamine tartrate with caffeine (Cafergot): tablet form
• Narrow or constrict blood vessels in the brain

Question 22

Triptans

Answer 22

• Stimulate 5-HT receptors in cerebral arteries, causing vasoconstriction and reducing headache symptoms
• Reduce the production of inflammatory neuropeptides

Question 23

Adverse affects of triptans

Answer 23

• Vasoconstriction
• Irritation at injection site
• Tingling, flushing

Question 24

Adverse affects of Ergot Alkaloids

Answer 24

Nausea and vomiting
Cold or clammy hands and feet
Muscle pain
Dizziness
Others

Question 25

Sumatriptan (Imitrex)

Answer 25

- Original prototype drug for this class - Seven triptans - Slight pharmacokinetic differences exist between some of these products. - Effects are comparable overall.

Question 26

Analeptics

Answer 26

- Include doxapram and the methylxanthines aminophylline, theophylline, and caffeine. Sometimes used to treat neonatal and postoperative respiratory depression. - Used less frequently

Question 27

Doxapram (Dopram)

Answer 27

- Treatment of respiratory depression associated with anesthetic drugs and drugs of abuse, COPD-induced hypercapnia - Monitor deep tendon reflexes, in addition to vital signs and heart rhythm, to prevent overdosage of this drug.

Question 28

Caffeine Found in:

Answer 28

- Analeptic - Over-the-counter drugs: NoDoz - Combination prescription drugs: Fioricet, Fiorinal - Foods and beverages

Question 29

Caffeine Use with caution in patients with a history of:

Answer 29

- Peptic ulcer - Recent myocardial infarction - Dysrhythmias

Question 30

Methylxanthines | Mechanism of Action:

Answer 30

- Inhibit phosphodiesterase, leading to buildup of cyclic adenosine monophosphate (cAMP) - Analeptic

Question 31

Caffeine | Mechanism of Action:

Answer 31

-Antagonizes adenosine receptors

Question 32

Analeptic Adverse Effects

Answer 32

``` -Vagal Stimulation of gastric secretions, diarrhea, and reflex tachycardia -Vasomotor Flushing, sweating -Respiratory Elevated respiratory rate -Musculoskeletal Muscular tension and tremors ```

Question 33

Nursing Implications: | Drugs for ADHD

Answer 33

- Last daily dose should be given 4 to 6 hours before bedtime to reduce insomnia. - Take on an empty stomach 30 to 45 minutes before meals. - Drug “holidays” may be ordered. - Instruct parents to keep a journal to monitor the child’s response to therapy. - Monitor the child for continued physical growth, including height and weight

Question 34

Nursing Implications: | Anorexiants

Answer 34

- Follow instructions for diet and exercise. - Take in the morning. - Avoid caffeine - Fat-soluble vitamin supplementation may be needed.

Question 35

Nursing Implications: | Selective Serotonin Receptor Agonists (SSRAs)

Answer 35

- Dissolvable wafers, nasal spray, and self-injectable forms - Provide specific teaching about correct administration. - Instruct patients to keep a journal to monitor response to therapy.

Question 36

Nursing Implications: | Ergot alkaloids

Answer 36

Chest pain, confusion, slurred speech, and vision changes need immediate medical attention.

Question 37

Nursing Implications: | Analeptics

Answer 37

Pay close attention to the ABCs because of the patient’s diminished sensorium

Question 38

Nursing Implications: | Monitor for therapeutic responses

Answer 38

- ADHD: decreased hyperactivity, increased attention span and concentration - Anorexiant: appetite control and weight loss - Narcolepsy: decrease in sleepiness - Serotonin agonist: decrease in frequency, duration, and severity of migraines