22.2 Pharmacotherapy: Antidepressants Flashcards
(75 cards)
1
Q
Describe the onset of effects of antidepressants (2)
A
- relief of neuro-vegetative/physical symptoms: 1-3 wk
- relief of emotional/cognitive symptoms: 2-6 wk
2
Q
Describe tapering of antidepressants (2)
A
- tapering of most antidepressants is usually required to avoid withdrawal reactions;
- speed of taper is based on the medication’s half-life and the patient’s individual sensitivity
3
Q
Name an antidepressant that does not require a taper
A
fluoxetine does not require a taper due to its long half-life
4
Q
Name antidepressants that require a slower taper than sertraline or citalopram
A
paroxetine and venlafaxine require a slower taper than sertraline or citalopram
5
Q
Describe the treatment of bipolar depression with antidepressants (2)
A
- patients with bipolar disorder should only be treated with an antidepressant if combined with a mood stabilizer or antipsychotic
- monotherapy with antidepressants is not advisable as the depression can switch to mania
6
Q
Name examples of SSRIs (6)
A
- fluoxetine (Prozac®)
- fluvoxamine (Luvox®)
- paroxetine (Paxil®)
- sertraline (Zoloft®)
- citalopram (Celexa®)
- escitalopram (Cipralex®)
7
Q
Explain use of fluoxetine (Prozac®) (5)
A
Useful for
- typical and atypical depression
- seasonal depression
- anxiety disorders
- OCD
- eating disorders
8
Q
Compare effectiveness of SSRIs (1)
A
All SSRIs have similar effectiveness but consider side effect profiles and half-lives
9
Q
Name the SSRIs that have the fewest drug-interactions and are sleep-wake neutral (2)
A
Citalopram, and escitalopram
10
Q
Name the safest SSRI in pregnancy and breastfeeding
A
Sertraline is the safest
11
Q
Name the most activating SSRI (recommend taking in the AM)
A
Fluoxetine (Prozac®)
12
Q
Name the most used SSRI in children
A
Fluoxetine is the most used in children as it has most evidence
13
Q
Fluoxetine does not require a taper why?
A
due to long half-life
14
Q
Describe: Fluvoxamine (Luvox®) (2)
A
- Fluvoxamine is sedating (should be taken in PM)
- can be involved in many drug-drug interactions
15
Q
Name examples of SNRIs (3)
A
- venlafaxine (Effexor®)
- Desvenlafaxine (Pristiq®)
- duloxetine (Cymbalta®)
16
Q
SNRIs are useful for what? (3)
A
Useful for depression, anxiety disorders, neuropathic pain
17
Q
Name example norepinephrine and dopamine reuptake inhibitors NDRI (1)
A
bupropion (Wellbutrin®)
18
Q
Bupropion (Wellbutrin®) is useful for what? And not recommended for what? (2)
A
- Useful for depression, seasonal depression
- not recommended for anxiety disorder treatment because of stimulating effects
19
Q
Name pros and cons of Wellbutrin (2)
A
- Causes less sexual dysfunction (may reverse effects of SSRIs/SNRIs), weight gain, and sedation
- Increased risk of seizures at higher doses
20
Q
Name contraindications of wellbutrin (5)
A
Contraindicated with
- history of seizure
- stroke
- brain tumour
- brain injury
- closed head injury
21
Q
Name examples tricyclic antidepressants (3º Amines) (2)
A
- amitriptyline (Elavil®)
- imipramine (Tofranil®)
22
Q
Name TCA (3º Amines) useful for OCD (1)
A
Clomipramine (Anafranil)
23
Q
Describe: TCA (3º Amines) (5)
A
- Useful for OCD (clomipramine)
- melancholic depression
- requires ECG monitoring
- check blood levels if using higher dosage
- highly lethal in overdose
24
Q
Name examples TCA (2º Amines) (2)
A
- nortriptyline (Aventyl®)
- desipramine (Norpramin®)
25
Describe TCA (2º Amines) (4)
* Preferred to tertiary amines because of lower propensity for anticholinergic adverse effects
* requires ECG monitoring
* check blood levels if using higher dosage
* highly lethal in overdose
26
Name examples of monoamine oxidase inhibitors MAOI (2)
* phenelzine (Nardil®)
* tranylcypromine (Parnate®)
27
Describe monoamine oxidase inhibitors MAOI (2)
* Useful for moderate/severe depression that does not respond to other antidepressants, atypical depression;
* requires strict adherence to MAOI diet
28
Name example reversible inhibition of MAO-A (RIMA) (1)
moclobemide (Manerix®)
29
Describe use: Reversible inhibition of MAO-A (RIMA) (1)
Useful for depression that does not respond to other antidepressants
30
Describe example: Noradrenergic and specific serotonin antagonists (NASSA) (3)
Useful in depression with prominent features
* insomnia
* agitation
* cachexia
31
Describe treatment Approach for Depression (5)
* **optimization**: increase dosage to maximum tolerated or highest therapeutic dosage
* **augmentation**: the addition of a medication that is not considered an antidepressant to an antidepressant regimen (i.e. thyroid hormone, lithium, atypical antipsychotics [aripiprazole, quetiapine, olanzapine, risperidone])
* **combination**: the addition of another antidepressant to an existing treatment regimen (i.e. the addition of bupropion or mirtazapine to an SSRI or SNRI)
* switch: change of the primary antidepressant (within or outside a class)
* note: it is important to fully treat depression symptoms (i.e. to remission) to decrease relapse rates
32
Name antidepressants that are worst in terms of 5HT2C/5HT2A in brain activation (insomnia, anxiety)
* Fluoxetine
* Paroxetine
33
Describe effect/side effect: Post-Synaptic Serotonin Receptor Stimulated
* 5HT1A centrally
* 5HT2A in spinal cord
* 5HT2C/5HT2A in brain
* 5HT3A in gut
34
Describe mode of action: SSRI (1)
Block serotonin reuptake only
35
Describe side effects: SSRI (14)
* Fewer than TCA, therefore increased compliance
* CNS:
* restlessness
* tremor
* insomnia
* headache
* drowsiness
* GI:
* N/V
* diarrhea
* abdominal cramps
* Weight gain
* Sexual dysfunction:
* erectile dysfunction
* anorgasmia
* CVS:
* increased HR
* Serotonin syndrome SIADH
* EPS
36
Describe Risk in overdose: SSRI (1)
Relatively safe in OD
37
Describe drug interactions: SSRI (3)
* MAOI
* SNRI
* Some SSRIs (fluoxetine, fluvoxamine, paroxetine) strongly inhibit cytochrome P450 enzymes, therefore will affect levels of drugs metabolized by P450 system
38
Describe mode of action: SNRI (1)
Block norepinephrine and serotonin reuptake
39
Describe side effects: SNRI (7)
* Low dose side effects similar to SSRIs (serotonergic)
* Higher dose side effects:
* tremors, tachycardia
* sweating
* insomnia
* orthostatic hypotension
* increase in BP (noradrenergic)
* SIADH
40
Describe risk of overdose: SNRI (2)
Tachycardia and N/V seen in acute overdose
41
Describe drug interactions: SNRI (3)
* MAOI
* SSRI
* Low inhibition of cytochrome P450 compounds
42
Describe mode of action: TCA (1)
Block norepinephrine reuptake (clomipramine also blocks serotonin reuptake)
43
Describe side effects: TCA (11)
* Anticholinergic effects:
* Dry mouth
* urinary retention
* constipation
* blurred vision
* confusional states
* Noradrenergic effects:
* tremors
* tachycardia
* sweating
* α-1 adrenergic effects:
* orthostatic hypotension
* falls
* QRS prolongation
44
Describe risk of overdose: TCA (4)
* Toxic in OD
* 3 times therapeutic dose may be lethal
* Presentation: anticholinergic effects, CNS stimulation, then depression and seizures
* ECG: prolonged QRS and QTc (reflect severity)
45
Describe tx of overdose: TCA (6)
* activated charcoal
* cathartics
* supportive treatment
* IV diazepam for seizure
* physostigmine salicylate for coma
* Do not give ipecac, as can cause rapid neurologic deterioration and seizures
46
Describe drug interactions: TCA (3)
* MAOI
* SSRI
* EtOH
47
48
Name example: MAOI (1)
Phenelzine
49
Describe mode of action: MAOI (1)
Irreversible inhibition of monoamine oxidase A and B increases duration that NE and 5HT are in the synaptic cleft by preventing their degradation
50
Name side effets: MAOI (10)
* Antihistamine effects: sedation, weight gain
* CVS:
* orthostatic hypotension
* hypertensive crises with tyramine rich foods (i.e. wine, cheese):
* headache
* flushes
* reflex tachycardia
* postural hypotension
* sedation
* insomnia
* weight gain
* Minimal anticholinergic and antihistamine effects
51
Describe risk in overdose: MAOI (2)
* Toxic in OD
* but wider margin of safety than TCA
52
Describe drug interactions: MAOI (2)
* Hypertensive crises with noradrenergic medications (i.e. TCA, decongestants, amphetamines)
* Serotonin syndrome with serotonergic drugs (i.e. SSRI, SNRI, tryptophan, dextromethorphan)
53
Name example: NDRI (1)
Buproprion
54
Describe mode of action: NDRI (1)
Block norepinephrine and dopamine reuptake
55
Name side effects: NDRI (12)
* CNS:
* dizziness
* headache
* tremor
* insomnia
* CVS:
* dysrhythmia
* HTN
* GI:
* dry mouth
* N/V
* constipation
* decreased appetite
* Other:
* agitation
* anxiety
56
Describe risk in overdose: NDRI (2)
Tremors and seizures seen in overdose
57
Describe drug interaction: NDRI (2)
* MAOI
* Drugs that reduce seizure threshold: antipsychotics, systemic steroids, quinolone antibiotics, antimalarial drugs
58
Name example: RIMA (1)
Moclobemide
59
Describe mode of action: RIMA (2)
* Reversible inhibitor of monoamine oxidase
* A leads to increased duration NE and 5HT are in the synaptic cleft by preventing their degradation
60
Name side effects: RIMA (13)
* CNS:
* dizziness
* headache
* tremor
* insomnia
* CVS:
* dysrhythmia
* hypotension
* GI:
* dry mouth
* N/V
* diarrhea
* abdominal pain
* dyspepsia
* GU:
* delayed ejaculation
* Other: diaphoresis
61
Describe risk in overdose: RIMA (1)
Risk of fatal overdose when combined with SSRIs, SNRIs or clomipramine
62
Describe drug interaction: RIMA (3)
* MAOI
* paroxetine
* Opioids
63
Name example: NASSA (1)
Mirtazapine
64
Describe mode of action: NASSA (1)
Enhance central noradrenergic and serotonergic activity by inhibiting presynaptic a-2 adrenergic receptors
65
Name side effects: NASSA (7)
* CNS:
* sedation
* dizziness
* Endocrine:
* increase in cholesterol
* triglycerides
* weight gain
* GI:
* constipation
* ALT
66
Describe risk in overdose: NASSA (1)
Relatively safe in OD
67
Describe drug interactions: NASSA (2)
MAOI, RIMA
68
Describe: Serotonin Syndrome (4)
* thought to be due to over-stimulation of the serotonergic system
* can result from medication combinations such as SSRI+SNRI, SSRI or SNRI +MAOI, SSRI+tryptophan, MAOI+meperidine, MAOI+tryptophan
* rare but potentially life-threatening adverse reaction to SSRIs and SNRIs
* important to distinguish from NMS
69
Describe symptoms: Serotonin Syndrome (9)
* nausea
* diarrhea
* palpitations
* chills
* diaphoresis
* restlessness
* confusion
* and lethargy
* but can progress to myoclonus, hyperthermia, rigor, and hypertonicity
70
Describe tx: Serotonin Syndrome (2)
* discontinue medication
* and administer emergency medical care as needed
71
Name sx: Discontinuation Syndrome (6)
FINISH
* Flu-like symptoms
* Insomnia
* Nausea
* Imbalance
* Sensory disturbances
* Hyperarousal (anxiety/agitation)
72
Describe: Discontinuation Syndrome (3)
* caused by the abrupt cessation of some antidepressants
* symptoms usually begin within 1-3 d
* consider avoiding drugs with a short half-life
73
Name most common drugs that cause Discontinuation Syndrome (3)
* paroxetine, fluvoxamine, and venlafaxine (drugs with shortest half-lives)
74
Describe tx: Discontinuation Syndrome (2)
* symptoms may last between 1-3 wk
* but can be relieved within 24 h by restarting antidepressant at the same dosage the patient was taking and initiating a slower taper over several weeks
75
Name: Symptoms of Antidepressant Discontinuation (6)
**FINISH**
* **F**lu-like symptoms
* **I**nsomnia
* **N**ausea
* **I**mbalance
* **S**ensory disturbances
* **H**yperarousal (anxiety/agitation)
