MOA drugs

Question 1

MOA Benzos?

Answer 1

Enhance the effect of gamma-aminobutyric acid (GABA)

Question 2

MOA memantine?

Answer 2

NMDA receptor antagonist

Question 3

Frequently Bend - During Barbeque?

Answer 3

increased FREQUENCY of Cl channels = BENZOS

increased DURATION of Cl channels = BARBITURATES

Question 4

How to withdraw Benzo?

Answer 4

Withdraw in steps of approx 1/8th every 2 weeks

Question 5

Side effects of antipsychotics? x7

Answer 5

• NMS
• increased VTE risk
• hyperprolactinaemia
• impaired glucose tolerance
• antimuscarinic (dry mouth, blurred vision, urine retention, constipation
• reduced seizure threshold
• prolonged QT

lethargy/drowsy
Parkinsonism

Question 6

MOA antipsychotics?

Answer 6

Dopamine D2 receptor antagonists, blocking dopaminergic transmission in the mesolimbic pathways

Question 7

EPSEs of antipsychotics? (3)

Answer 7

Parkinsonism

1) acute dystonia
- sustained muscle contraction (e.g. torticollis, oculogyric crisis)
- procyclidine
2) akathisia (severe restlessness)
3) tardive dyskinesia (late onset of choreoathetoid movements, abnormal, involuntary, most common is chewing and pouting of jaw)

Question 8

SE of antipsychotics in elderly?

Answer 8

Increased risk of stroke

Increased risk of vTE

Question 9

SE TCAs?

Answer 9

• drowsiness
• dry mouth
• blurred vision
• constipation
• urinary retention
• lengthening of QT interval

Question 10

SE Lithium?

Answer 10

nausea/vomiting, diarrhoea
- fine tremor
- diabetes insipidus (polydipsia)
- hypothyroidism
ECG: T wave flattening/inversion
- weight gain
- idiopathic intracranial hypertension
leucocytosis
hyperparathyroidism and resultant hypercalcaemia

Question 11

Foods to avoid with MAO inhibitors?

Answer 11

cheese,
pickled herring,
Bovril, Oxo, Marmite,
broad beans

Question 12

What is the mechanism of action of venlafaxine?

Answer 12

SNRI - serotonin AND noradrenaline reuptake inhibitor

Question 13

Which antipsychotics are more likely to cause acute dystonic reactions e.g. oculogyric crisis?

Answer 13

TYPICAL: haloperidol, chlorpromazine

Question 14

Examples of atypical antipsychotics? Which has best side effect profile?

Answer 14

clozapine
olanzapine: higher risk of dyslipidemia and obesity
risperidone
quetiapine
amisulpride
aripiprazole: generally good side-effect profile, particularly for prolactin elevation

Question 15

SE of atypical antipsychotics?

Answer 15

1) weight gain
2) hyperprolactinaemia
3) dylipidaemia
4) clozapine - agranulocytosis

Question 16

Monitoring o lithium in stable patient?

Answer 16

bLOOD TEST 12 HOURS POST-DOSE EVERY 3 MONTHS

1 week after starting/changing dose, weekly until stable

Question 17

Class of drug - mirtazepine?

Answer 17

noradrenergic and specific serotonergic antidepressant

blocks alpha2 adrenoreceptors

Question 18

pseudo dementia?

Answer 18

Severe depression can mimic dementia but gives a pattern of global memory loss rather than short-term memory loss - this is called pseudodementia