Bipolar and Schizophrenia

Question 1

what is thought to be the MoA of lithium?

Answer 1

complex effects on the generation of intracellular second messengers

Question 2

why does lithium serum concentration need to be measured after 12hrs of first dosing then at least every 3 months?

Answer 2

it has a narrow therapeutic index

Question 3

how is lithium excreted and what effects does this have?

Answer 3

it is excreted by glomerular filtration and 80% is reabsorbed in the proximal tubule by the same mechanism as sodium so if the body is depleted of salt and water e.g. by vomiting, diarrhoea, then enhanced reabsorption of Na is accompaned by enhanced lithium reabsorption whcih can produce toxicity

Question 4

name some side effects of lithium

Answer 4

• Nausea
• diarrhoea
• CNS effects (tremor, giddiness, ataxia, dysarthria, mild cognitive and memory impairment)
• hypothyroidism during long-term treatment
• severe toxicity can cause coma, convulsions, profound hypotension, oliguria

Question 5

what drugs can lithium interact with adversely?

Answer 5

• diuretics (may reduce lithium excretion by depleting intravascular volume)
• ACE-inhibitors and angiotensin II receptor antagonists and soem NSAIDs can reduce renal excretion of lithium
• increased risk of extra-pyramidal side effects when taken with antipsychotic drugs

Question 6

what class of drug is carbamazepine and what can it be used in?

Answer 6

anticonvulsant - can be used for bipolar.

however, it has a delayed onset of action so may be given initially with a benzo

Question 7

how long can it take lithium to reach therapeutic effect?

Answer 7

1 week

Question 8

what is an alternative to lithium for the acute phase in bipolar?

Answer 8

sodium valproate as its sedative action produces a response in 1-4 days

Question 9

what is the treatment for severe manic symptoms in bipolar?

Answer 9

lithium/sodium valproate/carbamazepine + antipsychotic drug (atypical one usually preferred)

Question 10

how is depression in bipolar often treated

Answer 10

quetiapine OR
lithium + antidepressant (antidpressants risk provoking switch to mania)
OR
olanzapine + SSRI fluoxetine or lamotrigine

Question 11

what is an alternative monotherapy to lithium in bipolar disorder?

Answer 11

Quetiapine

Question 12

what can be used for refractory episodes of mania and depression which has a more rapid action than drug therapy?

Answer 12

ECT

Question 13

name 4 conventional antipsychotics

Answer 13

• haloperidol
• chlorpromazine
• flupentixol
• sulpiride

Question 14

name 5 atypical antipsychotics

Answer 14

• risperidone
• olanzapine
• clozapine
• aripiprazole
• quetiapine

Question 15

why should kidney function be monitored when someone is on lithium?

Answer 15

because it has severe renal toxicity

Question 16

what tests should be done before starting antipsychotics and then annually thereafter?

Answer 16

FBC
U&Es
LFTs
fasting blood glucose (measure at 6 months)

Question 17

what should be measured at baseline then at 3 months then yearly when on antipsychotics?

Answer 17

blood lipids and weight

Question 18

which antipsychotic is effective in treatment resistance schizophrenia?

Answer 18

clozapine

Question 19

why does clozapine need close monitoring?

Answer 19

due to risk of agranulocytosis

Question 20

what is the mechanism of action of antipsychotics?

Answer 20

D2 receptor antagonist mainly but also antagonist actviity at alpha-1 adrenoceptors and histamine H1 receptors.

Question 21

name some examples of the depot preparations of antipsychotics

Answer 21

flupentixol
decanoate
zuclopenthixol decanoate

Question 22

what are unwanted effects of conventional antipsychotics?

Answer 22

• extrapyramidal side effects (acute dystonias, akathisia, parkinsonism)
• tadive dyskinesia is a late adverse effect resulting in pointless, involuntary and repetitive movements (e.g. lip smacking) which may not resolve on stopping dose
• drowsiness and cognitive impairment
• galactorrhoea
• increased risk of osteoporosis
• erectile dysfunciton and impaired arousal
• neuroleptic malignant syndrome
• drowsiness
• hypotension
• QT prolongation (and consequent arrhythmias)
• weight gain (think of olanzapine begins with an ‘O’ so makes people round, fat)
• antimuscarinic effects

Question 23

what would acute dystonia present as?

Answer 23

tongue protrusion, torticollis (wry neck), oculogyric crisis (eyes rolled up into head)

Question 24

what is akathisia?

Answer 24

restlessness

Question 25

what is a depot version of atypical antipsychotics

Answer 25

olanzapine embonate

Question 26

what 2 side effects are unique to clozapine

Answer 26

reduced seizure threshold and agranulocytosis (an acute condition involving severe and dangerous leukopenia - lowered WBC count, most commonly neutrophils

Question 27

what is the optimal length of treatment for antipsychotics in schizophrenia?

Answer 27

2-5yrs

Question 28

what group of people should antipsychotics be prescribed to with extra caution?

Answer 28

elderly due to increased mortality and morbidity riso

Question 29

what monitoring is required for patients on antipsychotics?

Answer 29

• BMI
• Bloods for kidney function and FBC
• ECG
• lipid profile

Question 30

before starting antipsychotics, what should be recorded as a baseline?

Answer 30

• weight
• waist circumference
• pulse
• BP
• fasting blood glucose, HbA1c, blood lipid profile
• prolactin levels
• assessment of movement disorders
• assessment of nutritional status, diet and level of physical activity
• offer ECG if cardiovascular risk or if an inpatient