22. Drugs used in Psychiatric Disease

Question 1

What are the general action of CNS drugs?

Answer 1

Stimulators or blockers of neurotransmitter release. Or can act as inhibitors of regulatory enzymes.

Question 2

What is the formulation of psychiatric disorders?

Answer 2

Genetic vulnerability + life events + individual personality/coping skills/social support + environmental influences.

Question 3

What are the core symptoms of depression?

Answer 3

Low mood, anhedonia (loss of enjoyment in previously enjoyable activities).

Question 4

What are the secondary symptoms of depression?

Answer 4

Decreased appetite, sleep disturbance, physical aches and pains, irritability, self harm or suicidal ideas/acts, psychotic symptoms.

Question 5

What is the monoamine hypothesis of depression?

Answer 5

Deficiency of monoamine neurotransmitters (NA and serotonin) so drugs that deplete these could induce depression.

Question 6

What is the neurotransmitter receptor hypothesis of depression?

Answer 6

Abnormality in the receptors for monoamine transmission leads to depression. So depletion of NTs causes compensatory up regulation of post synaptic receptors.

Question 7

What is the monoamine hypothesis of gene expression for depression?

Answer 7

Deficiency in molecule functioning.

Question 8

What are the types of antidepressants?

Answer 8

Monoamine oxidase inhibitors, monoamine uptake inhibitors, others.

Question 9

What are the types of monoamine uptake inhibitors?

Answer 9

Non-selective noradrenalin and serotonin, selective noradrenaline or serotonin.

Question 10

What are selective serotonin reuptake inhibitors use for?

Answer 10

Moderate to severe depression (with CBT).

Question 11

Name an SSRI.

Answer 11

Fluoxetine, citalopram, paroxetine, sertraline.

Question 12

What are the pharmokinetics of SSRIs? (Absorption, half lives, metabolism).

Answer 12

Absorbed in gut, long half life, metabolised in liver.

Question 13

What are the ADRs of SSRIs?

Answer 13

Common - anorexia, nausea, diarrhoea. Rare - precipitation of mania, increased suicidal ideation.

Question 14

Name a tricyclic antidepressant.

Answer 14

Amitryptiline, imipramine, clomipramine, lofepramine.

Question 15

What are the actions of TCAs?

Answer 15

Inhibit NA uptake so enhanced NA neurotransmission, muscarinic cholinoceptor blockade-reduced cholinergic neurotransmission, alpha-1 adrenoceptor blockade-suppression of NA neurotransmission.

Question 16

What are the ADRs of TCAs?

Answer 16

CNS - sedation and impairment of psychomotor performance. ANS - reduced glandular secretions. CVS - tachy, postural hypotension. GI - constipation.

Question 17

Which drug family is more dangerous in OD - SSRIs or TCAs?

Answer 17

TCAs.

Question 18

Name a pure non-selective monoamine uptake inhibitor (SNRIs).

Answer 18

Venlafaxine, duloxetine.

Question 19

In what way are SNRIs dose dependent?

Answer 19

Lower doses - serotonin action, higher doses - noradrenline action.

Question 20

What are the ADRs of SNRIs?

Answer 20

Sleep disturbance, increased BP, dry mouth, hyponatraemia, withdrawal on discontinuation.

Question 21

What is psychosis?

Answer 21

Lack of contact with reality.

Question 22

What are the symptoms of paranoid schizophrenia?

Answer 22

Disturbed thinking, hallucinations, delusions, unusual speech-thought disorder, behavioural change, lack of insight.

Question 23

What is a hallucination?

Answer 23

Perception in the absence of an external stimulus.

Question 24

What is a delusion?

Answer 24

Fixed false belief that is out of keeping with someone’s culture or religious beliefs.

Question 25

What is the dopamine theory of schizophrenia?

Answer 25

Amphetamine causes symptoms like positive ones of schizophrenia and dopamine antagonists are the best treatment.

Question 26

How is the dopamine theory of schizophrenia limited?

Answer 26

It doesn't account for the negative symptoms.

Question 27

What are the main dopamine pathways?

Answer 27

Mesolimbic (emotional response and behaviour), mesocortical (arousal and mood), nigrostriatal, tuber-hypophyseal.

Question 28

What are the effects of D2 antagonists?

Answer 28

Nigrostriatal pathway -> Parkinsonian symptoms; mesocortical -> enhance negative symptoms; tuberoinfundibular -> hyperprolactinaemia; mesolimbic -> massively reduces positive psychotic symptoms.

Question 29

What is the suggested link between schizophrenia and 5HT function?

Answer 29

Increased 5HT has been linked with disturbed behaviours in schizophrenia.

Question 30

What is the suggested link between schizophrenia and cortical glutamate function?

Answer 30

Glutamate is an excitatory neurotransmitter, decreased function is associated with schizophrenia.

Question 31

What are the drugs used in schizophrenia?

Answer 31

First generation - haloperidal, chlorpromazine; atypical antipsychotics - olaznapine, risperideone, quetiapine; clozapine.

Question 32

What are the actions of all antipsychotics? (From hours to weeks).

Answer 32

Within hours - sedation and tranquilisation. Hours to days - extrapyramidal side effects. Days to weeks - antipsychotic effects and activating effect.

Question 33

Why are atypical antipsychotics more acceptable to patients with schizophrenia?

Answer 33

Less EPSE ADRs, once daily dosing, differing side effect profiles to match some patients.

Question 34

What are the ADRs of atypical antipsychotics in schizophrenia?

Answer 34

Varies drug-to-drug, EPSE at high doses, weight gain, increased prolactin, sedation.

Question 35

Which typical antipsychotic is safe in schizophrenic emergencies?

Answer 35

Haloperidol.

Question 36

What are the ADRs of typical antipsychotics in schizophrenia?

Answer 36

EPSE, neuroleptic malignant syndrome, postural hypotension, weight gain, endocrine changes, pigmentation.

Question 37

What are the toxicity risks of typical antipsychotics in schizophrenia?

Answer 37

CNS depression, cardiac toxicity, risk of sudden death with high dose.

Question 38

What makes up an anxiety disorder?

Answer 38

Fear out of proportion to situation leading to avoidance.

Question 39

What are the physical symptoms of anxiety?

Answer 39

Light headedness, shortness of breath, hot and cold flushes, nausea, palpitations, numbness, pins and needles.

Question 40

What is the treatment line of anxiety?

Answer 40

Non-pharmacological approaches, treat coexistent disorders, antidepressants, anxiolytics.

Question 41

Name a benzodiazepine.

Answer 41

Diazepam, lorazepam.

Question 42

What is the mechanism of action of benzodiazepines in anxiety?

Answer 42

Binds BDZ receptor to have inhibitory effects. Enhances GABA.

Question 43

Explain what is meant by tolerance and dependence with use of benzodiazepines.

Answer 43

Tolerance - need to increase the dose to achieve the same effect. Dependence on discontinuation of treatment - withdrawal effects.

Question 44

What are the ADRs of benzodiazepines?

Answer 44

Common - drowsiness, dizziness, pyschomotor impairment. Occasional - dry mouth, blurred vision, GI upset, ataxia, headache, reduced BP. Rare - amnesia, restlessness, rash.

Question 45

How are cases of overdose of benzodiazepines treated?

Answer 45

Support, flumazenil as antagonist to inverse BDZ receptor agonism.

Question 46

What is bipolar spectrum disorder?

Answer 46

Depression and hypomania/mania.

Question 47

What are the symptoms of bipolar spectrum disorder?

Answer 47

Unusually excited/happy/optimistic/irritable, overactive, poor concentration and short attention span, poor sleep, rapid speech, poor judgement, hypersexuality, psychotic symptoms.

Question 48

What are the mood stabilisers used in bipolar spectrum disorder?

Answer 48

Lithium, sodium valproate, carbamazepine, lamotrigine, antipsychotics.

Question 49

What is the mechanism of action of lithium?

Answer 49

Competes with Mg and Ca ion channels, increases 5HT but reduces if chronic use, attenuates effects of NT on receptors.

Question 50

Why does lithium need monitoring?

Answer 50

Due to narrow therapeutic window, need to check: renal function, thyroid function every 6 months.

Question 51

What are the uses of lithium?

Answer 51

Prophylaxis of mania and depression, augmentation of antidepressants in unipolar depression, reduce suicidality.

Question 52

What are the ADRs of lithium?

Answer 52

Memory problems, thirst, polyuria, tremor, drowsiness, weight gain.

Question 53

What are the toxic effects of lithium?

Answer 53

Vomiting, diarrhoea, coarse tremor, dysarthria, cognitive impairment, restlessness, agitation.

Question 54

How is lithium toxicity treated?

Answer 54

Supportive measures, anticonvulsants, increase fluid intake, haemodialysis.

Question 55

What are the two groups of dementia medication? Give an example of each.

Answer 55

Acetyl cholinesterase inhibitors - donepezil, galantamine, rivastigmine. NMDA antagonist - memantine.

Question 56

What is the action of AChE-I in dementia treatment?

Answer 56

Slows progression of Alzheimers.

Question 57

What are the ADRs of AChE-I?

Answer 57

Nausea, vomiting, anorexia, diarrhoea, fatigue insomnia, headache, bradycardia, worsening COPD, gastric/duodenal ulcers.

Question 58

What are the ADRs of memantine in dementia?

Answer 58

Hypertension, dyspnoea, headache, dizziness, drowsiness.