Psychopharmacology – Other Psychoactive Drugs

Question 1

Benzodiazepines:

Answer 1

Benzodiazepines include diazepam (Valium), alprazolam (Xanax), and lorazepam (Ativan).

Benzodiazepines are effective for short-term management of anxiety, insomnia, and seizures, but their long-term use should be avoided due to the risk of dependence and other adverse effects. They should be used cautiously, particularly in older adults, and never in combination with alcohol due to the risk of serious complications.

Question 2

Benzodiazepines: Uses

Answer 2

Anxiety disorders.
Insomnia.
Seizures.
Alcohol withdrawal.

Question 3

Benzodiazepines: Mechanism

Answer 3

Increase the activity of gamma-aminobutyric acid (GABA), a neurotransmitter that inhibits the activity of neurons, leading to calming effects.

Question 4

Benzodiazepines: Side Effects

Answer 4

Drowsiness and sedation (common).
Weakness and unsteadiness.
Impaired memory and concentration.
Anticholinergic effects.
Sexual dysfunction.
Paradoxical effects (e.g., excitability, anxiety).
Tolerance, dependence, and withdrawal symptoms with chronic use.
Rebound anxiety and depression, anorexia, delirium, seizures with withdrawal.
Lethal synergistic depressant effect when combined with alcohol.

Question 5

Benzodiazepines: Precautions

Answer 5

Use with caution in older adults due to the risk of disorientation and confusion.
Avoid long-term use due to the risk of tolerance, dependence, and withdrawal symptoms.
Gradually taper off benzodiazepines to avoid withdrawal symptoms.

Question 6

Barbiturates - Definition

Answer 6

Central nervous system depressants, including thiopental, amobarbital, and secobarbital.

Question 7

Barbiturates: Uses

Answer 7

Anesthesia induction, anxiety, insomnia, and certain types of seizures.

Question 8

Barbiturates: Mechanism of Action

Answer 8

Enhances GABA activity, leading to neuronal hyperpolarization and reduced excitability.

Question 9

Barbiturates: Side Effects

Answer 9

Drowsiness, dizziness, confusion, ataxia, paradoxical excitement, respiratory depression, dependence, withdrawal.

Question 10

Barbiturates: Precautions

Answer 10

Short-term use, cautious tapering, avoidance of alcohol and other depressants.

Question 11

Barbiturates: Considerations

Answer 11

Limited use due to high risk of dependence, tolerance, and withdrawal. Prefer safer alternatives for anxiety and insomnia.

Question 12

Azapirones

Answer 12

Definition: Anxiolytic drugs, including buspirone (BuSpar).
Uses: Generalized anxiety disorder and other anxiety disorders.
Mechanism of Action: Partial agonist at serotonin receptors, particularly 5-HT1A receptors.
Side Effects: Dizziness, dry mouth, sweating, nausea, headache.
Advantages: Non-sedating, lacks dependence and tolerance development.
Precautions: Slow onset of action, may not be effective for severe anxiety.
Considerations: Suitable for long-term use, especially in patients prone to substance abuse or dependence.

Question 13

Narcotic-Analgesics (Opioids)

Answer 13

Drugs mimicking effects of endorphins/enkephalins.

Question 14

Narcotic-Analgesics (Opioids)
Types

Answer 14

Natural opioids (opium, morphine, heroin, codeine), synthetic opioids (methadone, oxycodone, hydrocodone, fentanyl).

Question 15

Narcotic-Analgesics (Opioids)
Uses

Answer 15

Pre-surgery anesthesia, pain management, heroin detox (methadone).

Question 16

Narcotic-Analgesics (Opioids)
Mechanism

Answer 16

Bind to opioid receptors, inhibit pain signals.

Question 17

Narcotic-Analgesics (Opioids)
Side Effects

Answer 17

Dry mouth, nausea, pupil constriction, drowsiness, constipation, respiratory depression.
Overdose Effects: Convulsions, coma, death.

Question 18

Narcotic-Analgesics (Opioids)
Chronic Use Risks

Answer 18

Dependence, tolerance, withdrawal (flu-like symptoms, insomnia, cramps).

Question 19

Narcotic-Analgesics (Opioids)
Public Health Concerns

Answer 19

Leading cause of accidental deaths in the US (opioids).

Question 20

Narcotic-Analgesics (Opioids)
Treatment

Answer 20

Medication-assisted therapy, rehabilitation programs, naloxone for overdose.

Question 21

Beta-Blockers

Answer 21

Function: Inhibit sympathetic nervous system activity.
Uses: Hypertension, cardiac arrhythmias, migraine, essential tremor.
Example: Propranolol (Inderal).
Additional Use: Anxiety treatment, especially for somatic symptoms.
Side Effects: Hypotension, decreased libido, insomnia, nausea, dry eyes, dizziness, depression.
Discontinuation: Abrupt withdrawal contraindicated (rebound hypertension, tremors, headaches).

Question 22

Mood Stabilizers

Answer 22

The mood stabilizers are used to treat bipolar disorder and include lithium and anticonvulsant medications.

Question 23

Lithium

Answer 23

Function: First-line drug for acute mania and classic bipolar disorder.
Brand Names: Eskalith, Lithobid.
Common Side Effects: Nausea, vomiting, diarrhea, metallic taste, increased thirst, weight gain, hand tremor, fatigue, impaired memory, and concentration.
Monitoring: Regular lithium levels check to avoid toxicity.
Toxicity Symptoms: Seizures, coma, death.

Question 24

Anticonvulsant Drugs

Answer 24

Uses: Treat acute mania and bipolar disorder with mixed episodes.
Examples: Carbamazepine (Tegretol), valproic acid (Depakene).
Side Effects: Nausea, dizziness, sleepiness, lethargy, ataxia, tremor, visual disturbances, impaired concentration.
Monitoring: Blood levels to avoid liver failure (valproic acid, carbamazepine), agranulocytosis, aplastic anemia (carbamazepine).

Question 25

Drugs for Treating Alzheimer’s Disease

Answer 25

Cholinesterase Inhibitors: Delay breakdown of acetylcholine.
Examples: Tacrine (Cognex), donepezil (Aricept), rivastigmine (Exelon), galantamine (Razadyne).
Approved for mild, moderate, and severe Alzheimer’s disease (except tacrine).
Side Effects: Vary but can include gastrointestinal issues, dizziness, and insomnia.
NMDA Receptor Antagonist: Regulates glutamate activity.
Example: Memantine (Namenda).
Approved for moderate to severe Alzheimer’s disease.
Side Effects: May include dizziness, headache, and confusion.

Question 26

Psychostimulants for ADHD

Answer 26

Types: Methylphenidate (Ritalin, Concerta), pemoline (Cylert), amphetamine-dextroamphetamine (Adderall).
Purpose: First-line treatment for ADHD.
Effects: Increase attention, concentration; reduce hyperactivity, impulsivity.
Mechanism: Increase dopamine, norepinephrine activity in prefrontal cortex.
Side Effects: Insomnia, nervousness, decreased appetite, weight loss, abdominal pain.
Concerns: Growth suppression in children (reversible with “drug holidays”).
College Use: Some use by students, but evidence suggests limited cognitive enhancement.

Question 27

Atomoxetine (Strattera)
Other Drugs for ADHD

Answer 27

Purpose: Non-stimulant medication for ADHD.
Mechanism: Selective norepinephrine reuptake inhibitor.
Effects: Improves attention, reduces impulsivity and hyperactivity.
Side Effects: Nausea, decreased appetite, insomnia, fatigue.

Question 28

Guanfacine (Intuniv)
Other Drugs for ADHD

Answer 28

Purpose: Alpha-2 adrenergic agonist used for ADHD.
Mechanism: Stimulates alpha-2 receptors, reducing sympathetic outflow.
Effects: Improves attention, reduces impulsivity.
Side Effects: Sedation, fatigue, dizziness, hypotension.

Question 29

Disulfiram (Antabuse)
Drugs for Alcohol Use Disorder

Answer 29

Purpose: Causes unpleasant symptoms when alcohol is consumed.
Effects: Nausea, vomiting, shortness of breath, headache.
Mechanism: Inhibits alcohol metabolism, leading to acetaldehyde buildup.

Question 30

Naltrexone (ReVia)
Drugs for Alcohol Use Disorder

Answer 30

Purpose: Reduces cravings and pleasurable effects of alcohol.
Effects: Decreased alcohol cravings.
Mechanism: Opioid antagonist, blocks alcohol-induced euphoria.

Question 31

Acamprosate (Campral)
Drugs for Alcohol Use Disorder

Answer 31

Purpose: Reduces alcohol cravings.
Effects: Decreased desire to drink alcohol.
Mechanism: Modulates neurotransmitter systems involved in alcohol dependence.

Question 32

Tetrahydrocannabinol (THC)

Answer 32

Description: Main active ingredient in cannabis.
Effects: Psychoactive; stimulates dopamine release in ventral striatum.
Function: Acts on mesolimbic dopaminergic reward pathway.
Medication: Dronabinol oral solution (Syndros).
Approved Uses:
Treatment of anorexia and weight loss in AIDS patients.
Management of chemotherapy-induced nausea and vomiting in cancer patients unresponsive to other antiemetics.

Question 33

Drug Half-Life

Answer 33

Definition: Time needed for blood level of drug to decrease to 50% of peak level.
Use: Determines time interval between doses.
Short Half-Life: Shorter interval between doses.
Long Half-Life: Longer interval between doses.
Age-related Changes: Older adults may have longer half-life due to metabolism changes.
Prescribing Rule: “Start low and go slow” for older adults due to increased sensitivity and longer half-life.
Example: Benzodiazepines have longer half-life in older adults, requiring longer elimination time.

Question 34

Drug Tolerance and Cross-Tolerance

Answer 34

Tolerance Definition: Gradual reduction in drug effects with repeated use.
Effect: Higher doses needed for same effect.
Cross-Tolerance: Tolerance to one drug extends to others in same class.
Example: Tolerance to alcohol leads to tolerance to benzodiazepines and barbiturates.
Mechanism: Shared pharmacological actions among drugs in same class.
Clinical Implications: Increased risk of overdose, dependence, and withdrawal.

Question 35

Therapeutic Index (TI)

Answer 35

Definition: Measures a drug’s safety.

Question 36

Therapeutic Index (TI)
Calculation

Answer 36

Animal Studies: LD50/ED50
Human Studies: TD50/ED50

Question 37

Therapeutic Index (TI)
LD50 (Lethal Dose 50)

Answer 37

Minimum dose lethal to 50% of test sample.

Question 38

Therapeutic Index (TI)
ED50 (Effective Dose 50)

Answer 38

Minimum dose producing desired effect in 50% of sample.

Question 39

Therapeutic Index (TI)
TD50 (Toxic Dose 50):

Answer 39

Minimum dose causing toxicity in 50% of sample.

Question 40

Therapeutic Index (TI)
TI Value

Answer 40

TI ≤ 1.0: Narrow therapeutic window, higher risk.
TI > 1.0: Wide therapeutic window, lower risk.

Question 41

Therapeutic Index (TI)
Clinical Implications

Answer 41

Narrow TI requires close monitoring.
Wide TI indicates safer drug.