Psychiatric Medication Flashcards
1
Q
What are some common adrenergic effects?
A
Sweating Tremor Headaches Nausea Dizziness
2
Q
What are some common muscarinic effects?
A
Dry mouth Difficulty swallowing Thirst Difficulty urinating Urinary retention Hot flushes Dry skin
3
Q
What are some common effects of histamine?
A
Dry mouth
Drowsiness
Dizziness
Nausea and vomiting
4
Q
Most antidepressants have their effect in how many weeks?
A
2 to 3 (up to 4-6)
5
Q
What are the most commonly used antidepressants?
A
SSRIs
6
Q
Other than SSRIs, what other types of antidepressants are there?
A
SNRIs
Mirtazapine
Tricyclics
MAOIs
7
Q
How do SSRIs work?
A
They reduce presynaptic reuptake of serotonin after its release into the cleft.
As a result, more seratonin is in the nerve junction.
This also leads to a down regulation of post synaptic receptors
8
Q
What are common side effects of SSRIs?
A
Sense of restlessness, agitation on initiation
Nausea, GI disturbance
Headache
Weight changes
Sexual dysfunction
Less common: bleeding and suicidal ideation
(One of the first things to improve is motivation rather than outlook. More likely to carry out harmful acts - follow up within 2 weeks of prescribing)
9
Q
SSRIs have low risk of bleeding so ask about other drugs that can cause bleeding e.g aspirin and cover with ….
A
A PPI
10
Q
What are some common SSRIs and dose range?
A
Sertraline 50-200mgs (therapeutic dose is 100mgs but start lower)
Citalopram 20-40mgs
Fluoxetine 20-60mgs
Paroxetine 20-60mgs
11
Q
Sertraline is safest in what type of disease?
A
Cardiac
12
Q
What is there a risk of with citalopram?
A
QTc prolongation
Not used in older patients for this reason
13
Q
Fluoxetine has a long half life, so when switching what is the risk?
A
Serotonin syndrome
14
Q
Does paroxetine have a short or long half life?
A
Short
Need to watch out for discontinuation syndrome
15
Q
How do SNRIs work?
A
Act in the same way as SSRIs but bind to noradrenaline reuptake receptors as well.
16
Q
What are the common side effects of SNRIs?
A
Similar to SSRIs but greater potential for sedation, nausea and sexual dysfunction
17
Q
Give two examples of SNRIs
A
Duloxetine (60-120mgs) low dose range
Venlafaxine (75-375mgs) greater efficacy and can go to a higher dose. Caution with higher doses in heart disease, monitor BP at doses above 225mgs
18
Q
What is mirtazapine?
A
Noradrenergic and Specific Serotonergic Antidepressant (NASSA)
Acts as a 5HT-2 and 5HT-3 antagonist
Strong H1 activity - hence sedation and increased appetite
19
Q
What are the major side effects of mirtazapine?
A
Sedation
Weight gain
These side effects can be used to therapeutic advantage e.g if depression complicated by anxiety or trouble sleeping
20
Q
Tricyclic antidepressants are useful in what situation?
A
For those who do not respond well to SSRIs
21
Q
Why are SSRIs favoured over TCAs?
A
Better tolerated side effect profile
22
Q
What is the action of TCAs?
A
Block the reuptake of noradrenaline and seratonin at the synaptic cleft
23
Q
What side effects are associated with TCAs?
A
Muscarinic and histaminic side effects
24
Q
Why can TCAs be fatal in overdose?
A
Cause QTc prolongation and arrhythmias
25
In low doses TCAs can be used for what purpose?
Neuropathic pain
26
Give some examples of TCAs
amitriptyline, clomipramine, imipramine
lofepramine, nortriptyline = newer TCAs and are tolerated better than older TCAs
27
How do monoamine oxidase inhibitors work?
They inhibit one or both monoamine oxidase enzymes MAOI-A, MAOI-B and thus inhibit the breakdown of monoamine neurotransmitters
28
What does MAOI-A work more on?
Serotonin
MAOI-B works more on dopamine
29
What are MAOIs generally reserved for?
Atypical depression
Dysthymia - chronic treatment resistant depression
30
Which MAOIs bind irreversibly and are more dangerous?
Phenelzine
| Isocarboxazid
31
Which MAOIs bind reversibly?
Moclobamide
| Tranylcypromine
32
MAOIs have the potential to cause what type of reaction leading to hypertensive crisis?
Tyramine reaction
33
What should be avoided when taking MAOIs?
Cheese, pickled meats, wine and other tyramine products
34
How long should the washout period be after taking MAOIs?
Up to 6 weeks
35
How does vortioxetine work?
All sorts of serotonergic activity
36
When should vortioxetine be considered?
No improvement after 2 other antidepressants have been tried
37
What is the most common side effect for vortioxetine?
Nausea
But generally well tolerated
38
What should be considered when deciding on an antidepressant?
What has been used before and was it effective/ tolerated?
| Are there comorbidities that can be addressed e.g weight loss, insomnia, neuropathic pain
39
Which antidepressant should be used in new cases with no previous treatment (and no major weight loss or sleep difficulty)?
Start with SSRI - SERTRALINE
In most cases start with SSRI, then switch to different SSRI if no effect, then try SNRI or Mitazapine
40
What type should be considered if comorbid neuropathic pain?
SNRI
41
For depression, if an antidepressant has no benefit at typical dose is it worth increasing dose?
No
If partial benefit can increase dose
42
For anxiety especially OCD, should you consider increasing the dose of antidepressant if no initial benefit at typical dose?
Yes
43
What is discontinuation syndrome?
Symptoms that occur after antidepressant is stopped
44
What symptoms are associated with discontinuation syndrome?
Sweating, shakes, agitation, insomnia, headaches, irritability, N&V, paraesthesia, clonus
Symptoms influenced by half life - shorter half life bigger the problem
45
What antidepressants are most difficult to stop - risk of discontinuation syndrome?
Paroxetine
| Venlafaxine
46
Why can switching to fluoxetine help in preventing discontinuation syndrome?
It has a very long half life
47
What is serotonin syndrome?
A group of symptoms that occur due to taking serotonergic drugs, typically 2 at the same time e.g an SSRI and SNRI
48
What symptoms are associated with serotonin syndrome?
Cognitive – headaches, agitation, hypomania, confusions, coma
Autonomic – shivering, sweating, hyperthermia, tachycardia, nausea
and diarrhoea
Somatic – myoclonus, hyper-reflexia and tremor
49
How is serotonin syndrome treated?
Usually supportive - fluids and monitoring
50
What are antipsychotics also called?
Neuroleptics
51
How do current antipsychotics work?
Reduce level of dopamine activity at D2 receptors
52
What dopaminergic pathways do antipsychotic medication target?
Mesocortical and mesolimbic
53
The unwanted effects of antipsychotics common from action at what pathways?
Nigrostriatal (movement) and tuberoinfundibular (HPA axis)
54
What side effects do all antipsychotics have the potential for?
```
Sedation
Extrapyramidal side effects
Weight gain
QTc prolongation
Acute dystonia
Oculogyric crisis
```
55
What are some characteristics of typical antipsychotics?
Older
More likely to cause extra-pyramidal side effects
Tend to bind more to muscarinic and histaminic receptors
56
What are other names for typical and atypical antipsychotics?
```
Typical = first generation
Atypical = second generation
```
57
Give some examples of typical antipsychotics
```
Haloperidol
Flupenthixol
Zuclopenthixol
Chlorpromazine
Sulpride
```
58
Give some examples of atypical antipsychotics
```
Clozapine
Olanzapine
Risperidone
Quetiapine
Amisulpride
Aripiprazole
```
59
What side effects are associated with typical antipsychotics?
Extra-pyramidal side effects including Parkinsonism (bradykinesia, muscle stiffness, tremor), tarditive dyskinesia, akathisia
Dizziness
Sexual dysfunction
60
What is akathisia?
A movement disorder characterised by a feeling of inner restlessness and inability to stay still
61
What is tardive dyskinesia?
Involuntary repetitive body movements e.g sticking tongue out, lip smacking, grimacing.
There may also be jerky movements
62
What side effects are associated with atypical antipsychotics?
Weight gain
Dyslipidaemia
Diabetes
63
Outline the monitoring that should be done for antipsychotics
Baseline: FBC, lipids, LFT, HbA1c, weight, ECG, BP and pulse
Weekly: weight
Three months: FBC, lipids, LFT, HbA1c, weight, ECG, BP and pulse
Yearly: same as above
64
What is neuroleptic malignant syndrome?
A rare, life threatening reaction to antipsychotics
65
What characteristics are associated with neuroleptic malignant syndrome?
Fever, confusion, muscle rigidity, sweating, autonomic instability
66
In NMS what is death usually caused by?
Rhabdomyolysis
Renal failure
Seizures
67
What are risk factors for NMS?
High potency dopamine antagonists (typical antipsychotics) in antipsychotic naive, high doses, young men
68
What will bloods likely show in NMS?
Raised CK
| Raised WCC
69
How do you treat NMS?
Stop antipsychotics
Benzodiazepine for acute behavioural disturbance
Fluid resuscitation
Reduce temp - cooling blankets
Oxygen if necessary
If rhabdomyolysis - fluids and sodium bicarbonate
To relax muscles - dantrolene or lorazepam
70
What medication is used to treat extra pyramidal side effects?
Anticholinergics (Ach antagonists)
71
Extra pyramidal side effects are due to what ratio in the nigrostriatal pathway?
Dopamine: acetylcholine
72
If there is too much acetylcholine in relation to dopamine and dopamine cannot be increased, what should be done?
Reduce acetylcholine
73
What is the most commonest drug used for EPSE?
Procyclidine
74
Are anticholinergics effective for tardive dyskinesia?
No - may exacerbate
75
What is acute dystonia?
Sustained, often painful muscular spasms producing twisted, abnormal postures.
Most common: neck, tongue, jaw, oculogyric crisis
76
What is oculogyric crisis?
Neck arched and eyes rolled back
77
How do you treat acute dystonias?
Stop antipsychotics
IM or IV anticholinergics - procyclidine
Continue for 1 to 2 days after dystonia and consider long term prophylactic
78
What was the first atypical antipsychotic?
Clozapine
79
What is the most efficacious antipsychotic?
Clozapine
80
What receptors does clozapine act on?
D2 antagonist
5HT-2 antagonist
81
When should clozapine be used?
After 2 other antipsychotics have not been effective
82
What side effects are associated with clozapine?
Significant potential for agranulocytosis (especially neutrophils)
- close FBC monitoring weekly for first 18 weeks then fortnightly for up to a year then monthly
Significant potential for gastrointestinal hypo-mobility: constipation, potentially fatal bowel obstruction
Hypersalivation
Urinary incontinence
Autonomic dysregulation - dose titrate slowly up over 2 weeks and monitor vitals
83
How do you treat agranulocytosis associated with clozapine?
Stop clozapine
Stop marrow suppressing drugs e.g sodium valproate
Avoid other psychotics for a few weeks (if not possible use Aripiprazole as less marrow suppression potential)
Contact haematologist
Consider broad spec antibiotics
Lithium can increase WCC and neutrophils
GCSF (although tends to increase release of WBCs from marrow, not increasing turnover)
84
What are the main classes of drugs used in the treatment of anxiety?
Beta blockers (physical symptoms)
Benzodiazepines
Pregabalin
Antidepressants
85
How do beta blockers work in the treatment of anxiety?
Reduce autonomic nervous system activation.
86
What is the most often used beta blocker in the treatment of anxiety?
Propranolol
87
Propranolol should not be prescribed if the patient has...
Asthma
88
Which benzodiazepines are most typically used in the treatment of anxiety?
Diazepam (long half life)
| Lorazepam (shorter half life)
89
How do benzodiazepines work?
Bind to GABA receptors to potentiate the effect of GABA and therefore reduce the excitability of neurones.
= positive allosteric modulators of GABA receptor
90
Why should benzodiazepines be prescribed cautiously?
Significant potential for tolerance and dependence
91
What is the maximum amount of time benzodiazepines should be used for?
No more than 6 weeks
92
What are some examples of mood stabilisers?
Lithium
Anticonvulsants
Atypical antipsychotics
93
How does lithium act on the brain?
Mechanism unknown
| Lowers NA release and increases serotonin synthesis
94
Does lithium have a narrow or large therapeutic window?
Narrow
95
How regularly should serum lithium levels be measured?
Weekly after dose change until levels stable then every 3 months
96
Is it true or false that lithium reduces suicide?
True
| It also has a licence for reduction of self harm
97
What are the side effects of lithium?
```
GI disturbance
Metallic taste and or dry mouth
Fine tremor
Polydipsia and polyuria
Weight gain
```
98
What are the long term effects of lithium?
Hypothyroidism - usually reversible
Renal impairment - usually irreversible (occurs mostly above therapeutic doses)
Therefore U&Es and TFTs every 6 months
99
What are the symptoms/ signs of lithium toxicity?
Can be fatal
Confusion, coarse tremor, incontinence, nausea and vomiting, ataxia, seizures
100
How do you manage lithium toxicity?
Stop lithium
| Supportive measures - IV fluids, dialysis if necessary, benzodiazepines for seizures
101
How is lithium excreted?
Via kidneys
102
The potential for toxicity increases with what?
Dehydration
103
What drugs have the potential to interact with lithium and increase toxicity risk?
NSAIDS
loop diuretics
ACE inhibitors
104
What is the first line drug treatment for bipolar?
Quetiapine
105
What are the most commonly used anticonvulsants used in bipolar disorder?
Sodium valproate- avoid in women of child bearing age, check LFTs before and soon after starting
Carbamazepine
Lamotrigine - potential for Stevens Johnson Syndrome
Most anticonvulsants have potential for thrombocytopenia so check FBC
106
Abrupt cessation of lithium precipitates mania in up to what percentage of people?
50%
Discontinuation should be over 2-4 weeks
107
What is the target plasma level of lithium?
0.6-1 mmol/L
108
TCAs have antimuscarinic side effects. What are they?
Can’t pee
Can’t see (blurred vision)
Can’t spit (reduced saliva)
Can’t shit (constipation due to reduced GI motility)
