Dopamine System - 30

Question 1

What is psychosis?

Answer 1

Disorganized or irrational behavior

Question 2

What types of symptoms are there of schizophrenia?

Answer 2

Cognitive dysfunction, positive symptoms, and negative symptoms

Question 3

When does Schizophrenia arise?

Answer 3

Typically late teens-early 20s

Question 4

Other than genetics, what can cause schizophrenia?

Answer 4

Idiopathic, metabolic, drug induced (PCP, meth/amphetamine)

Question 5

What is the Dopamine hypothesis?

Answer 5

Schizophrenia is caused by overactive dopamine system; because drugs that block D2 dopamine receptors reduce symptoms

Question 6

Where is the imbalance of dopamine in regards to schizophrenia?

Answer 6

Increased limbic : decreased prefrontal cortex

Question 7

What evidence is there to support the dopamine hypothesis?

Answer 7

Blocking DA receptors improves symptoms; high doses of amphetamine produce similar paranoid psychosis symptoms; greater dopamine release in those w/ psychosis; inhibiting dopamine reduces symptoms of schizophrenia

Question 8

What will be seen in a brain 5 years after the onset of schizophrenia?

Answer 8

Loss of grey matter

Question 9

What brain regions are involved in schizophrenia (mainly)?

Answer 9

See P-Coats

Caudate, Prefrontal Cortex, Occipital cortex, Amygdala, Thalamus, Striatum

Question 10

Why might patients with Schizophrenia have impaired oral hygiene?

Answer 10

Inability to think clearly/plan

Question 11

What are some of the dental implications of Schizophrenia?

Answer 11

Heavy smokers/coffee drinkers; impaired gag reflex; xerostomia; drug interactions

Question 12

What is the strangest treatment for Schizophrenia?

Answer 12

Electroconvulsive Shock Therapy (still used today)

Question 13

What symptoms of schizophrenia are best treated by anti-psychotics?

Answer 13

Positive symptoms (there’s a snake in my boot….. no there’s not)

Question 14

What mechanism do anti-psychotics work by?

Answer 14

They interfere with Dopamine transmission (mostly block receptors)

Question 15

There is a strong relationship between _____________________ and ________________. (Treating schizophrenia)

Answer 15

Potency at the D2 DA receptor : effective dose

Better binding = lower dose needed

Question 16

What is the most commonly used First Generation Anti-psychotic drug?

Answer 16

Haloperidol

Question 17

What are the most common Second Generation Anti-psychotics?

Answer 17

Risperidone, Olanzapine, Aripiprazole

Question 18

What is a key pharmacological property of antipsychotic drugs?

Answer 18

High therapeutic index

Question 19

What other receptors (other than DA) do anti-psychotics work on that cause unwanted side effects?

Answer 19

Alpha-adrenergic, muscarinic Ach, histamine (activates), serotonin

Question 20

What are some unwanted side effects of antipsychotics (physiologically)?

Answer 20

Increased prolactin (on target); Poikilothermic effects; Antiemetic effects

Question 21

Characteristically, how are antipsychotics absorbed?

Answer 21

Erratically (unpredictably)

Question 22

What is the half life of antipsychotics?

Answer 22

6-40hrs

Question 23

How do antipsychotics react with the BBB?

Answer 23

Pass through easily (very lipophilic)

Question 24

S1/S2 - Patients who take antipsychotics for prolonged periods will build tolerance to the sedative effects. They will also build a tolerance to the prolactin secretion.

Answer 24

Statement 1 is true. Statement 2 is false

Question 25

T/F Antipsychotics are highly addictive

Answer 25

F

Question 26

What will happen if a patient stops taking their antipsychotics abruptly?

Answer 26

RELAPSE

Question 27

What are some unwanted side effects of antipsychotics (will ask why they happen)?

Answer 27

Sedation/CNS depression; Antimuscarinic; Antiadrenergic; Extrapyramidal (neurological)

Question 28

What causes the Sedation/CNS effects?

Answer 28

Activation of histamine receptors

Question 29

What are antimuscarinic effects?

Answer 29

Dry mouth/drowsiness

Question 30

Why are there neurological side effects?

Answer 30

Over-activation of dopamine receptors (receptors that aren’t blocked are now over-activated)

Question 31

What happens if you give too much Haloperidol?

Answer 31

Parkinsonian syndrome

Question 32

What are some of the neurological side effects?

Answer 32

Tardive dyskinesias (tics around the mouth)

Question 33

T/F Second generation anti-psychotics have much less side effects

Answer 33

T

Question 34

What percentage of D2Rs must be blocked for a therapeutic effect? Pyramidal effect?

Answer 34

60% : 80%

Question 35

What are the “affective disorders”?

Answer 35

Depression and Bipolar disorder

Question 36

What is the prevalence of depression? Onset?

Answer 36

17% : 11 yrs old

Question 37

What is required for a diagnosis of major depression?

Answer 37

> (or equal) 5/9 symptoms

Question 38

Why are those with depression prone to periodontitis/tooth decay?

Answer 38

Lower immune response; clenching; neglect oral hygiene; more lactobacillus; dry mouth (side effect)

Question 39

What is the goal of antidepressants?

Answer 39

To increase serotonin transmission

Question 40

What are the tricyclics antidepressant drugs?

Answer 40

Amitriptyline; Imipramine

Question 41

What is an example of an SSRI?

Answer 41

Fluoxetine (Prozac)

Question 42

How do Tricyclics antidepressants work?

Answer 42

They block the serotonin transporter

Question 43

What other issues can trycyclic antidepressants treat?

Answer 43

Trigeminal neuralgia and facial pain

Question 44

What does SSRI stand for? What’s good about them?

Answer 44

Selective Serotonin Reuptake Inhibitor. They only work on Serotonin receptors so no muscarinic/histaminic/adrenergic side effects

Question 45

What effect does SSRIs have on Benzos?

Answer 45

It inhibits P450s (prolongs effects)