CNS Flashcards Preview

Pharmacology > CNS > Flashcards

Flashcards in CNS Deck (22)
Loading flashcards...
1

Benzodiazepines (Lorazepam, Diazepam): Indications

Seizures and Status Epilectus
Symptomatic Management of Alcohol Withdrawal
SHORT term treatment of anxiety

2

Benzodiazepines (Lorazepam, Diazepam): Mechanism of Action

They enhance the binding of GABA to GABA receptors. These are Cl- channels so are inhibitory so has a widespread depressant effect

3

Benzodiazepines (Lorazepam, Diazepam): ADRs

Predictable! Drowsiness, sedation, coma
OD can cause respiratory depression and death

4

Benzodiazepines (Lorazepam, Diazepam): Warnings and Interactions

Caution in elderly as they are more sensitive
Avoid in respiratory depression and hepatic failure

Their effect are additive with opioids and alcohol. They depend of CYP450 metabolism for excretion

5

Benzodiazepines (Lorazepam, Diazepam): Prescription

Monitoring is based on signs and symptoms

6

Antipsychotics, 1st gen, typical (Haloperidol, chlorpromazine): Indications

Urgent management of psychomotor agitation
Schizophrenia
Bipolar disorder (particularly in acute setting)
N&V in pallition

7

Antipsychotics, 1st gen, typical (Haloperidol, chlorpromazine): Mechanism of Action

Block post-synaptic D2 receptors
Act on the 3 main dopaminergic pathways: mesolimbi, nigrostriatial, tuberohypophyseal
Also block D2 receptors in CTZ

8

Antipsychotics, 1st gen, typical (Haloperidol, chlorpromazine): ADRs

Mainly because of blockade of nigrostriatial pathway: parkinsonian movements, restlessness, muscle spasms
Also drowsiness and hypotension

9

Antipsychotics, 1st gen, typical (Haloperidol, chlorpromazine): Warnings and Interactions

Avoid in parkinsons!
There is an extensive list of interactions
Should not be combined with D2 blocking anti-emetics or QT prolonging drugs e.g. amiodarone/macrolides

10

Antipsychotics, 2nd gen, atypical (Clozapine, Olanzapine): Indications

Urgent treatment of psychomotor agitation
Schizophrenia, especially when 1st gen drugs cannot be used due to side effects
Bipolar

11

Antipsychotics, 2nd gen, atypical (Clozapine, Olanzapine): Mechanism of Action

Block post-synaptic D2 receptors
Act on the 3 main dopaminergic pathways: mesolimbi, nigrostriatial, tuberohypophyseal
Have fewer extrapyramidal side effects than 1st gen, possible because of some binding to other receptor types e.g. 5-HT

12

Antipsychotics, 2nd gen, atypical (Clozapine, Olanzapine): ADRs

Fewer extrapyramidal effects (spasm, restlessness, parkisonian movements)
More metabolic effects: weight gain, DM
Sedation, prolonged QT interval

13

Antipsychotics, 2nd gen, atypical (Clozapine, Olanzapine): Warnings and Interactions

Caution in heart disease
Should not be combined with D2 blocking anti-emetics or QT prolonging drugs e.g. amiodarone/macrolides

14

Antidepressants, SSRI (citalopram, fluoxetine): Indications

Moderate to severe depression
Mild depression if psychological treatments have failed
Anxiety

15

Antidepressants, SSRI (citalopram, fluoxetine): Mechanism of Action

Inhibit reuptake of 5-HT at synaptic cleft. Thus increases its availability of synaptic transmission. We reckon this is how they work...

16

Antidepressants, SSRI (citalopram, fluoxetine): ADRs

GI upset, appetite and weight disturbance, suicidal thoughts

17

Antidepressants, SSRI (citalopram, fluoxetine): Warnings and Interactions

They prolong the QT interaval
Metabolised by liver so caution in hepatic impairment
Poor efficacy and lots of suicidal thoughts when used in young people

MAOIs + SSRI = serotonin syndrome
Other drugs that prolong the QT interval

18

Antidepressants, SSRI (citalopram, fluoxetine): Prescription

Treatment tends to be long term and shouldn't be suddenly stopped due to withdrawal symptoms
Patients would be reviewed 1-2 weeks after starting therapy

19

Antiemetics, D2 antagonists (metoclopramide): Indications

N&V treatment and prophylaxis, particularly die to reduced gut motility

20

Antiemetics, D2 antagonists (metoclopramide): Mechanism of Actions

They block D2 receptors in the CTZ and increase gut motility

21

Antiemetics, D2 antagonists (metoclopramide): ADRs

Predictable due to D2 antagonism: spasm, parkinsonian movements, restlessness

22

Antiemetics, D2 antagonists (metoclopramide): Warnings and Interactions

Avoid in children and young adults
Avoid with anti-psychotics, due to increased side effects (as they are both blocking D2)
Avoid with dopaminergic agents in parkinson, as you'll spoil any benefit