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Flashcards in Psycho-Pharmacology Deck (59)
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1
Q

What mental health disorders are indicated for treatment with Antidepressants?

A
  • Unipolar and bipolar depression.
  • Organic mood disorders
  • Schizoaffective disorder
  • Anxiety Disorders
    • OCD
    • Panic
    • Social Phobia
    • PTSD
    • Premenstrual dysphoric disorder
    • Impulsivity associated personality disorders.
2
Q

What are the general principles for the use of antidepressants?

A
  • Antidepressants have similar efficacy, so choice is discerned by:
    • Past history of response
    • side effect profile
    • Coexisting medical conditions.
  • There is a delay of 3-6 weeks following maintenance at therapeutic dose before symptoms improve.
  • If no improvement is seen after a trial of adequate length (a tleast 2 months) and adequate dose, switch to different antidepressant or augment with another agent.
3
Q

What are the different classifications of antidepressants?

A
  • Tricyclics (TCAs)
  • Monoamine Oxidase Inhibitors (MAOIs)
  • Selective Serotonin Reuptake Inhibitors (SSRIs)
  • Serotonin/Noradrenaline Reuptake inhibitors (SNRIs)
  • Novel Antidepressants
4
Q

What are the general pros and cons of TCA use?

A

Pros

  • Very Effective

Cons

  • Potentially unacceptable side effect profile
    • antihistaminic
    • Anticholinergic
    • Antiadrenergic
  • Lethal in overdose (even a one week supply can be lethal!)
  • Can cause QT lengthening - even a therapeutic dose level.
5
Q

What are tertiary TCAs?

Act?

What is the negative of tertiary TCA use?

A
  • Have tertiary amine side chains
  • Act predominately on serotonin receptors.
  • Examples include:
    • Imipramine
    • Amitriptyline
    • Doxepin
    • Clomipramine
  • Have active metabolites - including desipramine and nortriptyline.

Negative

  • Side chains are more likely to cross-react with other receptors and lead to more side effects.
    • Antihistaminic
    • Antiadrenergic
    • Anticholiergic
    • Anticholinergic
    • Antiadrenergic
6
Q

What side effects are seen if a medication is:

  • Antihistaminic
  • Anticholinergic
  • Antiadrenergic
A
  • Antihistaminic
    • Sedation
    • Weight gain
  • Anticholinergic
    • Dry mouth
    • Dry eyes
    • Constipation
    • Memory deficits
    • Potentially delirium
  • Antiadrenergic
    • Postural hypotension
    • Sedation
    • Sexual dysfunction
7
Q

What are secondary TCAs?

Act?

SE?

Examples?

A
  • These are often metabolites of tertiary amines
  • Primarily block noradrenaline
  • Side effects are the same as tertiary TCAs, but generally less severe.
  • Examples:
    • Desipriramine
    • Notrtiptyline
8
Q

How do Monoamine Oxidase Inhibitors (MAOIs) work?

A
  • Bind irreversibly to monoamine oxidase, thereby preventing inactivation of amines such as norepinephrine, dopamine and serotonin leading to increased synaptic levels.
  • Are very effective for depression.
9
Q

What are the Side effects of MAOIs?

Other complications too.

A

Side Effects

  • Postural Hypotension
  • Weight gain
  • Dry mouth
  • Sedation
  • Sexual dysfunction
  • Sleep distrubance

Also

  • Hypertensive crisis can develop when MAOI’s are taken with tyramine-rich foods or sympathomimetics. (Cheese Reaction)
10
Q

What is the link between MAOI use and Serotonin Syndrome?

Sx of Serotonin Syndrome.

How is this avoided?

A
  • Serotonin Syndrome can develope if MAOIs are taken with other medications that increase serotonin or have sympathomimetic actions.

Symptoms of Serotonin Syndrome

  • Abdo. pain
  • Diarrhoea
  • Sweats
  • Tachycardia
  • HTN
  • Myoclonus
  • Irritability
  • Hyperpyrexia
  • CVS shock
  • Death

This is avoided by leaving a gap of 2 weeks between switching from an SSRI to an MAOI.

  • Except for fluoxetine - need to wait 5 weeks, due to long half-life.
11
Q

How do SSRIs work?

What do they treat?

A
  • They work by blocking the reuptake of serotonin in the presynaptic membrane.
  • Useful in treating depression and anxiety.
12
Q

What are the side effects of SSRIs?

A
  • GI upset
  • Sexual Dysfunction (30%+)
  • Anxiety
  • Restlessness
  • Nervousness
  • Insomnia
  • Fatigue
  • Sedation
  • Dizziness

When stopping can continue into a discontinuation syndrome with :

  • Agitation
  • Nausea
  • Disequilibrium (lack of stability)
  • Dysphoria - unease/dissatisfaction w/ life
13
Q

What is Paroxetine?

Pros and Cons ?

A

SSRI

Pros

  • Short half-life with no metabolites, means there is no build up (good if hypomania develops)
  • Sedational properties give initial relief if anxiety and insomnia - given at night.

Cons

  • Significant CYP2D6 (a liver enzyme) inhibition - may lead to toxicity of other drugs
  • SE - sedation, weight gain, anticholinergic effects
  • Likely cause discontinuation.
14
Q

What is Sertraline?

Pros and Cons?

A

SSRI

Pros

  • Lower impact on P450 (only slight CYP2D6)
  • Short half-life with limited metabolite build up
  • Less sedating that Paroxetine

Cons

  • Max absorption requires a full stomach
  • Increased GI adverse drug reactions.
15
Q

What is Fluoxetine (Prozac)?

Pros and Cons

A

SSRI

Pros

  • Long half life so less chance of discontinuation syndromes. This also makes it good for patients who have compliance issues.

Cons

  • Long half-life, and active metabolism may build up (this is not good if there is hepatic disease)
  • Significant p450) interaction - may not be a good choice in patients taking many drugs.
  • Initial activation may increase anxiety and insomnia.
  • More likely to induce mania than other SSRIs.
16
Q

What is Citalopram?

Pros and Cons

A

SSRI

Pros

  • Few drug-drug reactions due to limited P450 inhibition.
  • Intermediate half-life

Cons

  • QT interval prolonged with doses 10-30mg - over 40mg not allowed!
  • Can sedate (antagonises H1 histamine receptor)
  • GI Side Effects - however, the effects are less than sertraline.
17
Q

What is Escitalopram?

A

SSRI

Pros

  • Low overall inhibition of p450 - few drug-drug interactions
  • Intermediate half life
  • More effective than Citalopram.

Cons

  • Dose dependent QT interval prolongation in doses 10-30mg.
  • Nausea and Headaches are SE
18
Q

What is Fluvoxamine?

Pros and Cons?

A

SSRI

Pros

  • Shortest half life
  • analgesic properties

Cons

  • Shortest half life
  • GI distress, headaches, sedation, weakness
  • Inhibits some liver enzymes
19
Q

What are Serotonin/Norepinephrine reuptake inhibitors (SNRIs)?

Treats?

A
  • Inhibit both sertonin and noradrenergic reuptake similar to that of the TCAs.
  • However without the antihistamine, antiadrenergic or anticholinergic side effects.
  • Used to treat depression, anxiety and neuropathic pain.
20
Q

What is Venlafaxine?

Pros and COns

A

SNRI

Pros

  • Minimal drug interactions + noP450 activity
  • Short half life + fast renal clearance (no build up) - good for geriatrics.

Cons

  • Can increase diastolic BP 10-15 mmHg.
  • May cause significant nausea.
  • can have bad discontinuation syndrome, taper recommended after 2 weeks use.
  • QT prolongation
  • Sexual SEs (30%+)
21
Q

What is Duloxetine?

Pros and Cons

A

SNRI

Pros

  • Efficacy for physical symptoms of depression
  • Less BP increase than Venlafaxine

Cons

  • Liver enzyme inhibtior
  • high drop out rate
22
Q

What are the names of the 2 novel antidepressants?

A

Mirtazapine

Buproprion

23
Q

How does Mirtazapine work?

Pros and Cons

A

Pros

  • Different mechanism of action may provide a good augmentation strategy to SSRIs. Is a 5HT2 and 5HT3 receptor antagonist
  • Can be utilized as a hypnotic at lower doses secondary to antihistaminic effects

Cons

  • Increased cholesterol in some patients.
  • Very sedating at low doses. Can be activating above 30mg.
  • Weight gain.
24
Q

What are the Pros and Cons of Buproprion?

A

Pros

  • Good for use as an augmenting agent
  • Mechanism of action likely reuptake inhibition of dopamine and norepinephrine
  • No weight gain, sexual side effects, sedation or cardiac interactions
  • Low induction of mania
  • Is a second line ADHD agent - so consider if the patient has co-occurring diagnosis.

Cons

  • May increase seizure risk at high doses (450mg+) and should avoid in patients with Traumatic Brain Injury, bulimia and anorexia.
  • Does not treat anxiety unlike many other antidepressants and can actually cause anxiety, agitation and insomnia
  • Has abuse potential because can induce psychotic symptoms at high doses
25
Q

With what mental illnesses are Mood Stabilizers indicated?

A
  • Bipolar
  • Cyclothymia
  • Schizoaffective
26
Q

What are the different classes of Mood Stabalizers?

A

Lithium

Anticonvulsants

Antipsychotics

27
Q

What are the beenfits of using Lithium?

What factors predict a positive response to Lithium?

A
  • Only med. to reduce suicide rate.
  • Effective in long term prophylaxis of both mania and depressive episodes.

Positive predictors

  • prior long-term response or family member with good response
  • Classic pure mania
  • Mania followed by depression.
28
Q

How do you use Lithium?

A

Before

  • Check U&Es and TSH for baseline.
  • Preg test in woman (Ebstein’s anomaly) ​

Monitoring

  • Steady state achieved after 5 days - check 12 hours after last dose
  • WHen stable check 3 months and check TSH & creatinine every 6 months. ​

Goal

  • Blood level between 0.6-1.2
29
Q

What are the side effects of Lithium Use?

A
  • GI issues
    • reduced appetite
    • N/V
    • Diarrhoea
  • Thyroid abnormalities
  • Polyuria/polydypsia secondary to ADH antagonism. In a small number of patients can cause interstitial renal fibrosis.
  • Hair loss and acne
  • Decreased seizure threshold
  • Cognitive slowing
  • INduction tremor
30
Q

Outline the 3 levels of Lithium Toxicity and the associated side effects?

A

Mild - Levels 1.5 - 2.0

  • vomiting
  • diarrhoea
  • dizziness
  • ataxia
  • slurred speech
  • nystagmus

Moderate

  • N/V
  • Anorexia
  • Blurred vision
  • CLonic limb movements
  • Convulsions
  • Delirium
  • Syncope

Severe - >2.5

  • Generalised convulsions
  • Oliguria and renal failure
31
Q

What 3 names are given for anticonvulssants?

A
  • Valproic acid
  • Carbamazapine (everyones fave xoxo)
  • Lamatrigine
32
Q

What is valproic acid and what factors predict a positive response?

A
  • Valproic acid is as effective as Lithium in mania prophylaxis but is not as effective in depression prophylaxis.
  • Factors predicting a positive response:
    • rapid cycling patients (females>males)
    • comorbid substance issues
    • mixed patients
    • Patients with comorbid anxiety disorders
  • Better tolerated than Lithium
33
Q

What is required before someone is started on valproic acid?

A
  • Before med is started: baseline liver function tests (lfts), pregnancy test and FBC
  • Start folic acid supplement in women
  • Monitoring: Steady state achieved after 4-5 days -check 12 hours after last dose and repeat CBC and lfts
  • Goal: target level is between 50-125
34
Q

Side effects of valproic acid?

A
  • Thrombocytopenia and platelet dysfunction
  • Nausea, vomiting, weight gain
  • Sedation, tremor
  • Increased risk of neural tube defect 1-2% vs 0.14-0.2% in general population secondary to reduction in folic acid
  • Hair loss
35
Q

What is carbamazapine and its first line usage?

A
  • First line agent for acute mania and mania prophylaxis
  • Indicated for rapid cyclers and mixed patients
36
Q

What is required before starting a patient on carbamazepine?

A
  • Before med is started: baseline liver function tests, FBC and an ECG
  • Monitoring: Steady state achieved after 5 days -check 12 hours after last dose and repeat CBC and lfts
  • Goal: Target levels 4-12mcg/ml
  • Need to check level and adjust dosing after around a month because induces own metabolism.
37
Q

Side effects of carbamazapine?

A
  • Rash- most common SE seen
  • Nausea, vomiting, diarrhea
  • Sedation, dizziness, ataxia, confusion
  • AV conduction delays
  • Aplastic anemia and agranulocytosis (<0.002%)
  • Water retention due to vasopressin-like effect which can result in hyponatremia
  • Drug-drug interactions!
38
Q

What are some drugs that increase carbamazepine levels/and or toxicity?

A
  • Acetazolamide, cimetidine (both can cause rapid toxic reactions), clozapine (may act synergistically to suppress BM), diltiazem, INH, fluvoxamine, occasionally fluoxetine, erythromycin, clarithromycin, fluconazole, itraconazole, ketoconazole, metronidazole, propoxyphene, verapamil, diltiazem.
39
Q

What are some drugs that decrease carbamazepine levels/and or toxicity?

A

neuroleptics, barbiturates, phenytoin, TCA’s.

40
Q

What are the side effects of lamotrigine?

A
  • Nausea/vomiting
  • Sedation, dizziness, ataxia and confusion
  • The most severe are toxic epidermal necrolysis and Stevens Johnson’s Syndrome. The character/severity of the rash is not a good predictor of severity of reaction. Therefore, if ANY rash develops, discontinue use immediately.
  • Blood dyscrasias have been seen in rare cases.
  • Drugs that increase lamotrigine levels: VPA (doubles concentration, so use slower dose titration), sertraline.
41
Q

Please see table regarding approved indications of use in bipolar disorder:

A
42
Q

What are indications for use of antipsychotics?

A
  • Schizophrenia, schizoaffective disorder, bipolar disorder- for mood stabilization and/or when psychotic features are present, psychotic depression, augmenting agent in treatment resistant anxiety disorders.
43
Q

What are key pathways in the brain affected by dopamine?

A
  • Nigrostriatal
  • Mesolimbic
  • Mesocortical
  • Tuberoinfundibular
44
Q

Please explain the mesocortical pathway and its role:

A
  • Projects from the ventral tegmentum (brain stem) to the cerebral cortex.
  • This pathway is felt to be where the negative symptoms and cognitive disorders (lack of executive function) arise. Problem here for a psychotic patient, is too little dopamine.
45
Q

Please explain the mesolimbic pathway and its role:

A
  • Projects from the dopaminergic cell bodies in the ventral tegmentum to the limbic system.
  • This pathway is where the positive symptoms come from (hallucinations, delusions, and thought disorders). Problem here in a psychotic patient is there is too much dopamine.
46
Q

Please explain the nigrostriatal pathway and its role:

A
  • Projects from the dopaminergic cell bodies in the substantia nigra to the basal ganglia.
  • This pathway is involved in movement regulation. Remember that dopamine suppresses acetylcholine activity. Dopamine hypoactivity can cause Parkinsonian movements i.e. rigidity, bradykinesia, tremors), akathisia and dystonia
47
Q

Please explain the tuberoinfundibular pathway and it’s role:

A
  • Projects from the hypothalamus to the anterior pituitary.
  • Remember that dopamine release inhibits/regulates prolactin release. Blocking dopamine in this pathway will predispose your patient to hyperprolactinemia (gynecomastia/galactorrhea/decreased libido/menstrual dysfunction).
48
Q

Please explain how ‘typical’ antipsychotics work:

A
  • Are D2 dopamine receptor antagonists
  • High potency typical antipsychotics bind to the D2 receptor with high affinity. As a result they have higher risk of extrapyramidal side effects. Examples include Fluphenazine, Haloperidol, Pimozide.
  • Low potency typical antipsychotics have less affinity for the D2 receptors but tend to interact with nondopaminergic receptors resulting in more cardiotoxic and anticholinergic adverse effects including sedation, hypotension. Examples include chlorpromazine and Thioridazine.
49
Q

Please explain the work mechanism of ‘atypical’ antipsychotics:

A
  • Atypical agents are serotonin-dopamine 2 antagonists (SDAs)
  • They are considered atypical in the way they affect dopamine and serotonin neurotransmission in the four key dopamine pathways in the brain.
50
Q

What is Risperidone and how does it function + side effects?

A
  • Available in regular tabs, IM depot forms and rapidly dissolving tablet
  • Is and atypical but functions more like a typical antipsychotic at doses greater than 6mg
  • Increased extrapyramidal side effects (dose dependent)
  • Most likely atypical to induce hyperprolactinemia
  • Weight gain and sedation (dosage dependent)
51
Q

What is olanzapine, how does it function and what are the side effects?

A
  • Atypical
  • Available in regular tabs, immediate release IM, rapidly dissolving tab, depo form
  • Weight gain (can be as much as 30-50lbs with even short term use)
  • May cause hypertriglyceridemia, hypercholesterolemia, hyperglycemia (even without weight gain)
  • May cause hyperprolactinemia (< risperidone)
  • May cause abnormal LFT’s (2% of all patients)
52
Q

What is quetiapine, how does it function and what are the side effects?

A
  • Atypical
  • Available in a regular tablet form only
  • May cause abnormal LFT’s (6% of all patients)
  • May be associated with weight gain, though less than seen with olanzapine
  • May cause hypertriglyceridemia, hypercholesterolemia, hyperglycemia (even without weight gain), however less than olanzapine
  • Most likely to cause orthostatic hypotension
53
Q

What is Aripiprazole , how does it function and what are the side effects?

A
  • Available in regular tabs, immediate release IM formulation and depo form
  • Unique mechanism of action as a D2 partial agonist
  • Low EPS, no QT prolongation, low sedation
  • CYP2D6 (fluoxetine and paroxetine), 3A4 (carbamazepine and ketoconazole) interactions that the manufacturer recommends adjusted dosing. Could cause potential intolerability due to akathisia/activation.
  • Not associated with weight gain
54
Q

What is Clozapine , how does it function and what are the side effects?

A
  • Available in 1 form- a regular tablet
  • Is reserved for treatment resistant patients because of side effect profile but this stuff works!
  • Associated with agranulocytosis (0.5-2%) and therefore requires weekly blood draws x 6 months, then Q- 2weeks x 6 months)
  • Increased risk of seizures (especially if lithium is also on board)
  • Associated with the most sedation, weight gain and abnormal LFT’s
  • Increased risk of hypertriglyceridemia, hypercholesterolemia, hyperglycemia, including nonketotic hyperosmolar coma and death with and/or without weight gain
55
Q

What are some adverse affects relating to antipsychotics

A
  • Tardive Dyskinesia (TD)-involuntary muscle movements that may not resolve with drug discontinuation- risk approx. 5% per year
  • Neuroleptic Malignant Syndrome (NMS): Characterized by severe muscle rigidity, fever, altered mental status, autonomic instability, elevated WBC, CPK and lfts. Potentially fatal.
  • Extrapyramidal side effects (EPS): Acute dystonia, Parkinson syndrome, Akathisia
56
Q

What are some agents for EPS (extrapyramidal side effects)?

A
  • Anticholinergics such as benztropine, trihexyphenidyl, diphenhydramine
  • Dopamine facilitators such as Amantadine
  • Beta-blockers such as propranolol
  • Need to watch for anticholinergic SE particularly if taken with other meds with anticholinergic activity ie TCAs
57
Q

What are Anxiolytics?

A

Used to treat many diagnoses including panic disorder, generalized Anxiety disorder, substance-related disorders and their withdrawal, insomnias and parasomnias. In anxiety disorders often use anxiolytics in combination with SSRIS or SNRIs for treatment

58
Q

What is Buspirone (Buspar) and what are its pros and cons?

A
  • Anxiolytic
  • Pros:
    • Good augmentation strategy- Mechanism of action is 5HT1A agonist. It works independent of endogenous release of serotonin.
    • No sedation
  • Cons:
    • Takes around 2 weeks before patients notice results.
    • Will not reduce anxiety in patients that are used to taking BZDs because there is no sedation effect to “take the edge off.
59
Q

What are benzodiazapines and what are they used for?

A
  • Used to treat insomnia, parasomnias and anxiety disorders.
  • Often used for CNS depressant withdrawal protocols ex. ETOH withdrawal.
  • Side effects/cons
    • Somnolence
    • Cognitive deficits
    • Amnesia
    • Disinhibition
    • Tolerance
    • Dependence