Behavioral Med Drugs Flashcards

1
Q

What is the prototypical low-potency first gen antipsychotic?

A

Chlorpromazine (Thorazine)

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2
Q

What is the prototypical high-potency first gen antipsychotic?

A

Haloperidol (Haldol)

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3
Q

What are 5 examples of second gen antipsychotics?

A
Clozapine
Quetiapine (Seroquel)
Risperidone
Ziprasidone (Geodon)
Aripirazole (Abilify) - this has a unique MOA

(Olanzapine is used frequently in Rosh questions)

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4
Q

What is the therapeutic MOA of first gen antipsychotics?

A

Antagonize D2 receptors in the mesolimbic dopamine pathway

(Keep in mind this is non-selective, so antagonism of D2 receptors in other pathways also occurs – but is not therapeutic)

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5
Q

What are other receptor (non-therapeutic targets) effects of first generation antipsychotics?

A

Anti-H.A.M. (antagonize the following:)

H1 receptors: sedation; weight gain (may be related to 5HT2A block, along with glucose intolerance)

Alpha-1 receptors: orthostatic/hypotension, sexual dysfunction, cardiac problems (think arrhythmias), and seizures

Muscarinic receptors: dries everything up

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6
Q

First gen antipsychotics are indicated for what in schizophrenia? Why?

A

Positive symptoms only:

  • hallucinations
  • delusions
  • paranoia

Does not address negative symptoms; can potentially exacerbate negative symptoms.

This is because the first gen meds are non-specific in their dopamine antagonism activity. Decreasing dopamine activity in the mesolimbic system decreases positive symptoms; decreasing dopamine activity in the mesocortical system can INCREASE negative symptoms.

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7
Q

What is the pathophys/etiology of positive symptoms in schizophrenia?

A

Excess of dopamine in the mesolimbic system

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8
Q

What is the pathophys/etiology of negative symptoms in schizophrenia?

A

Deficiency of dopamine in the mesocortical system, secondary to excess serotonin

(or secondary to dopamine blocking caused by 1st gen antispsychotics/other drugs)

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9
Q

When an first gen antipsychotic drug acts on the nigrostriatal dopamine pathway, what occurs?

A

Dopamine suppresses ACh activity (via GABA), so blocking dopamine –> increased ACh activity –> adverse effects of the extrapyramidal system (EPS)

Dysfunction of the EPS = movement disorders

Deficiency of dopamine = Parkinson’s syndrome

Hyperactivity of dopamine = chorea, tics

Dopamine inhibition = akathisia (tense restlessness), dystonia (uncontrollable contractions/spasms -> repetitive movements), tardive dyskiniesia (similar, often involves face/head - smacking lips, sticking out tongue, etc)

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10
Q

When an first gen antipsychotic drug acts on the tuberoinfundibular dopamine pathway, what occurs?

A

The tuberoinfundibular pathway mediates dopamine from arcuate nucleus to the hypothalmus.

Dopamine release from the hypothalmus inhibits prolactin release from the pituitary gland.

Thus, dopamine blockade in the tuberoinfundibular pathway –> increased prolactin release.

Adverse effects include:

Women: breast engorgement; galactorrhea, amenorrhea

Women and men: sexual dysfunction, infertility

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11
Q

What is the therapeutic MOA of second-gen antipsychotics?

A

Weakly antagonize D2 receptors in the mesolimbic dopamine pathway (or weakly agonize)

Antagonize serotonin receptors in mesocortical system

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12
Q

Other than mesolimbic and mesocortical effects, what are some actions of second gen antipsychotics?

A

Nigrostriatal pathway:
Promotes dopamine release to compete with D2 block

Tuberoinfundibular pathway:
5Ht-stimulated prolactin release is blocked

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13
Q

Which antipsychotic class is likely to cause the MOST sedation?

A

Low-potency first generation (chlorpromazine)

All antipsychotics have the potential to cause some sedation

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14
Q

Which antipsychotic class is most likely to cause seizures?

A

First gen (haldol and chlorpromazine) AND clozapine (2nd gen)

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15
Q

What antipsychotic class is most likely to cause EPS symptoms?

A

First generation (especially high potency)

Also, risperidone (dose-dependent)

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16
Q

If a patient, who is otherwise stable on their antipsychotic medication, exhibits laryngospasm, what should be done?

A

Laryngospasm (as well as torticollis and oculogyric crisis) are forms of dystonia, which is an EPS side effect caused by increased ACh activity due to reduced dopamine levels.

Dystonia responds to anticholinergics.

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17
Q

If a patient, who is otherwise stable on their antipsychotic medication, exhibits repetitive lip smacking, what should be done?

A

This is a form of tardive dyskinesia, which is an EPS side effect caused by hypersensitivity of dopamine receptors after long-term suppression of dopamine release.

Change this patient’s antipsychotic to a second gen, as these symptoms can become permanent.

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18
Q

Which antipsychotic has the highest risk of prolonged QT interval?

A

*ZZ:

Ziprasidone and cloZapine

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19
Q

You have a patient with obesity who requires an antipsychotic. She reports no cardiac history. Which might be a good choice?

A

Aripiprazole has less potential for weight gain and less sedation.

Ziprasidone also has less potential for weight gain.

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20
Q

Which second gen antipsychotics are most associated with weight gain?

A

Clozapine

Risperdone, but this is a dose-dependent effect

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21
Q

Your patient tells you she has a history of “heart problems”. When considering an antipsychotic for her, what would be some considerations?

A

Ziprasidone and iloperidone have highest risk of QT prolongation.

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22
Q

Your patient has diabes and requires an antipsychotic medication. What are some considerations?

A

Many second gen antipsychotics cause hyperlipidemia, weight gain, and hyperglycemia.

  • Olanzipine has a high risk of metabolic effects
  • Arpiprazole and ziprasidone have the lowest risk of these side effects among the second gen (but do carry some risk of QT prolongation)
  • Or, maybe consider a first gen
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23
Q

Which antipsychotic agents are most likely to cause EPS symptoms?

A

High-potency first gen (haloperidol)

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24
Q

Which antipsychotic agents are most likely to cause anti-HAM effects?

A

Low potency first generation (chlorpromazine)

anti-HAM = histamine, a1, and muscarinic antagonism-related side effects + seizures

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25
Q

What is a miscellaneous adverse effect of quetiapine?

A

Formation of cataracts

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26
Q

What are some important considerations with the drug clozapine?

A
  • Agranulocytosis (esp first 6 mo of therapy) - monitor WBC and ANC weekly x 6 months, then two weeks, then monthly after 1 yr of tx
  • High risk of QT prolongation
  • Myocarditis
  • High potential for weight gain, hyperlipidemia, and hyperglycemia

+ Associated with decreased risk of suicide!

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27
Q

Your patient, who is being treated for schizoprenia, presents with agitation, confusion, fever, muscle rigidity, and BP/HR that is all over the place. Labs are run and are remarkable for increased CPK, LDH, and LFTs. What’s going on, and what do you do?

A

This patient has neuroleptic malignant syndrome, which can be fatal. Leukocytosis and/or rhabdomyolysis can be present in these patients.

This patient is most likely on a first generation antipsychotic.

Immediately dc the antipsychotic, give supportive care (ex: IV fluids, cooling blanket if hyperthermia is present).

Consider giving dantrolene, which can address the rigidity and fever.

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28
Q

What kind of regular screening should be performed on a patient who is taking a second gen antipsychotic?

A
  • Emergence of movement disorders
  • Weight/waist circumference

Metabolic screening:

  • ** FBG
  • ** HbA1c
  • ** FLP
  • plus stuff like response to tx, symptom profile, overall health, interactions, etc
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29
Q

You are prescribing your patient a first gen antipsychotic. What might you consider prescribing alongside the antipsychotic?

A

An antimuscarinic to prevent EPS symptoms, such as:

  • Benztropine
  • Trihexphenidyl
  • Diphenhydramine

(Unfortunately, 1st gen also have some anti-H.A.M. effects, so this guy is probably gonna be constipated. :/ )

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30
Q

Which antipsychotic should be avoided IV?

A

Haloperidol, due to increased risk for QT prolongation. Use it IM instead.

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31
Q

Name 5 drugs that might be used for a patient with bipolar disorder who is experiencing acute mania with signs of psychosis and severe agitation.

A

Haloperidol (1st gen antipsychotic)

Risperidone (2nd gen antipsychotic)

Benzodiazepines (tranquilizer)

Lithium (mood stabilizer)

Valproate (anti-convulsant used for mood stabilization)

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32
Q

What are some drugs that can be used for a patient with bipolar disorder who is experiencing an acute mania (without signs of psychosis)?

A

2nd gen antipsychotics (minus clozapine)

Plus:

  • Lithium
  • Carbamazepine
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33
Q

What are some medications that can be used for maintenance in a patient with bipolar disorder?

A

Some 2nd gen antipsychotics (asenapine, clozapine, olanzapine, quetiapine)

Plus:

  • Lithium
  • Valproate
  • Carbamazepine
  • Lamotrigine
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34
Q

What is a drug that might be used for maintenance of bipolar disorder but NOT for an acute mania?

A

Lamotrigine

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35
Q

What is a drug that might be used to treat an acute mania experienced by a patient with bipolar disorder, but is NOT indicated for maintenance?

A

Valproate

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36
Q

What is a drug that can be used for maintenance, acute mania, and acute mania with psychosis for a patient with bipolar disorder?

A

Lithium

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37
Q

What is the cause of the adverse effects associated with lithium?

A
  • Reduced 2nd messengers (IP3/DAG)
  • Inhibition of adenyl cyclase
  • Uncoupling of G proteins (vasopression and TSH receptors)
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38
Q

What is the first line treatment of bipolar 1, and what is its MOA?

A
  • Lithium
  • MOA:
    • Enhancement of serotonin action via facilitation of release
    • Attenuation of NE
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39
Q

What must be screened in a patient taking lithium?

A

Serum concentrations of the drug.

<1 mEq/L is used for maintenance

Slightly higher for acute phases

> 2 mEq/L is toxic

Anything more than 4 mEq/L is potentially fatal

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40
Q

What are some adverse effects of lithium?

A
  • Fine tremor
  • Sedation, dose-dependent
  • Slowing of AV conduction
  • GI effects: (nausea, loose stool)
  • Weight gain
  • Leukocytosis
  • Acne, psoriasis
  • Diabetes insipidus
  • Thyroid goiter/hypothyroidism

AE occur early in tx and are common

**Teratogenic

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41
Q

What are some signs of lithium toxicity?

A
  • Coarse tremor
  • Seizure
  • Arrhythmia
  • Vomiting and/or diarrhea
  • Tubular necrosis
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42
Q

What are some drugs/conditions that INCREASE lithium serum concentration?

A
  • Thiazide diuretics
  • NSAIDs
  • ACEIs
  • Dehydration
  • Reduced Na intake
  • Decreased GFR
  • Postpartum state (vs pregnancy)
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43
Q

What are some conditions that DECREASE lithium serum concentration?

A
  • Increased Na intake
  • Significant weight gain
  • Acute mania
  • Pregnancy
44
Q

What are 5 SSRIs?

A
  • Sertraline
  • Fluoxetine
  • Citalopram
  • Escitalopram
  • Paroxetine
45
Q

What are 4 SNRIs?

A
  • Venlafaxine
    • Desvenlafaxine
  • Duloxetine
  • Levo-milnacipran
46
Q

What are 3 “mixed” SSRIs?

A
  • Vilaozdone
  • Vortioxetine
  • Trazodone
47
Q

Example of an NDRI?

A

Bupropion

48
Q

Example of an NaSSA?

A

Mirtazapine

NaSSA = Noradrenergic, selective serotonergic antidepressant

49
Q

What are some cyclic/tricyclic antidepressants?

A
  • “triptyline”s:
    • amitryptiline
    • nortriptyline
    • protriptyline
  • “pramine”s:
    • desipramine
    • imipramine
    • trimipramine

Plus doxepin

50
Q

What are 4 MAOIs?

A

SPIT:

  • Selegiline
  • Phenelzine
  • Isocarboxazid
  • Tranylcypromine
51
Q

In SSRIs, effects on which receptor mediates the therapeutic effect?

A

Serotonin reuptake = increased serotonin in synaptic cleft. This excess serotonin then binds 5HT1A post-synaptic receptors in the prefrontal cortex, hippocampus, and amygdala, to mediate therapeutic effect.

52
Q

Your patient tends to be non-compliant with antidepressant medications and often forgets doses or will forget to refill his prescription for a week at a time. Which SSRI would be LEAST problematic for him?

A

Fluoxetine - long half-life makes it “self-tapering” and once-weekly dosing is an option.

53
Q

SSRIs + CYP inhibition

A
  • I’m not studying this in-depth; know that fluoxetine has most interactions and 2D6 is common among the SSRIs
54
Q

Common SSRI AE

A

GI
Sexual dysfunction
CNS (HA, fatigue, insomnia, tremor, restlessness)

55
Q

Patients with long QT syndrome should avoid which SSRI?

A

Citalopram and (escitalopram)

56
Q

Rare, serious AE of SSRIs

A

SIADH
Seizures
Serotonin syndrome
Excessive teeth grinding/jaw clenching (bruxism)

57
Q

Your patient is being treated for depression with insomnia. Which SSRIs would be least appropriate?

A

Fluoxetine

Sertraline

58
Q

Which SSRIs are most sedating?

A

Fluvoxamine

Paroxetine

59
Q

Your patient presents with depressive symptoms and insomnia. She is started on an SSRI and another “mixed action” antidepressant at a low dose. What is this antidepressant, and what is its MOA?

A
  • Trazadone. Doses lower than would be used in depression are used as an adjunct to SSRIs to manage depression-related insomnia.

It is not great as monotherapy for depression (sedation, orthostatic hypotension).

It is a an SSRI, (5HT2A antagonist), and an H1 antagonist.

60
Q

What is the MOA of vortioxetine?

A

SSRI

5HT1A agonist

5HT3 antagonist

61
Q

What is the MOA of Vilazodone?

A

SSRI

Partial 5HT1A agonist

62
Q

What receptors are targeted by SNRIs?

A

Post-synaptic a1A and 5HT1a receptors

63
Q

What are some AE associated with SNRIs that are not commonly experienced with SSRIs?

A
Sweating
Dry mouth
Elevated BP (usually mild, but monitor)
Elevated HR
Anxiety
Agitation

^^ due to noradrenergic effects

64
Q

Your patient struggles with both depression and chronic neuropathic pain. Which antidepressant might help both conditions?

A

Duloxetine (SNRI) has FDA approved indications for both depression and neuropathic pain.

65
Q

What is the MOA of mirtazapine?

A
  • PREsynaptic a2 antagonism ( –> increased NE and 5HT release)
  • Antagonizes some of the POST-synaptic receptors (lots of the 5HT receptors and also H1)
  • It increases 5HT and NE release, and blocks post-synaptic receptors that are associated with AEs.
66
Q

What is the MOA of bupropion?

A

Weakly inhibits norepinephrine and dopamine reuptake

No effects on 5HT receptors; also no anti-H.A.M. actions

67
Q

What are some AE of bupropion?

A
  • Seizures (esp with eating disorders)
  • Agitation/anxiety
  • Headache
68
Q

Which antidepressant would be best for use in a patient who is trying to quit smoking?

A

Bupropion

69
Q

What is the MOA of TCAs?

A

Block reuptake of any of the following:

 - NE
 - 5HT
 - Dopamine

+ anti-H.A.M. actions

70
Q

What are some AE that are common among TCAs?

A

Anti-H.A.M. effects (sedation, orthostatic hypotension, lowering of seizure threshold, drying out anti-muscarinic effects)

  • Lowers seizure threshold
  • Increased risk for sudden cardiac death (eval EKG before and during tx)
  • Arrhythmias (QT prolongation)
  • Sexual dysfunction
  • Weight gain
71
Q

What is the MOA of MAOIs?

A

Block monoamine oxidase enzyme = decreased breakdown of epi, 5HT, norepinephrine, and dopamine

(Also inhibits breakdown of dietary monoamines, such as tyramine, found in some cheeses, cured meats, etc)

72
Q

Indications for MAOIs?

A

Refractory depression

73
Q

Which MAOI can be administered via a transdermal patch?

A

Selegeline

74
Q

Your patient will be switching from an MAOI to another class of antidepressant. What should be considered?

A

A washout period of 5 half-lives is needed to rid system of metabolites.

Do not start a contraindicated drug until 2 weeks post termination of MAOI.

75
Q

Which antidepressants are most lethal in cases of overdose?

A

CAs and MAOIs

SSRIs can cause serotonin syndrome

76
Q

Therapy in case of CA overdose:

A

Administer activated charcoal (pt should pass charcoal)

Monitor for prolonged QT interval (increase pH via IV bicarbonate and hyperventilate the patient)

77
Q

What are some signs of MAOI toxicity?

A
Agitation
Hallucinations
Hyperpryrexia
Seizures
Labile BP
Threatening life
78
Q

Your patient is on an SSRI. Which drugs may increase the risk of serotonin syndrome in this patient?

A

Tramadol
CYP inhibitors
Sumatriptan
Other MAOIs - meperidine, dextromethorphan, linezolid

79
Q

Buspirone is indicated for what? What is its MOA?

A

Anti-anxiety, indicated for GAD
(Slowed onset of action (2-4) weeks, non-benzo)

MOA: partial agonist of 5HT1A

80
Q

What are some AE associated with buspirone?

A

Dizziness
Nervousness
HA

Some EPS AE possible; can cause restless leg syndrome

(Does NOT have the AE associated with benzos, because it is not a benzo! These include sedation, memory problems, fall risk, anterograde amnesia, respiratory depression, tolerance/dependence… on and on)

81
Q

What drug can be administered to reverse CNS-depressing effects of benzodiazapines?

A

Flumazenil - competitive antagonist

82
Q

Review the indications of benzodiazepines

A

(Alprazolam, chlordiazepam, diazepam, lorazepam, midazolam, clonazepam)

Continuum of uses: anxiety disorders (not first line), anticonvulsant, muscle relaxant, sedation, anesthesia

*Tunes everything down

83
Q

What drug is used acutely for severe anxiety episodes?

A

Benzodiazepines, IV or PO

*Add IV second gen antipsychotic if there are psychotic features present during anxiety crisis

84
Q

What drugs are used for chronic maintenance of anxiety disorders?

A
    • Antidepressants (SSRIs = first line)
  • Busprione (often used as adjunct to SSRI)
  • Antipyschotics (probably not likely)

(Pharmacotherapy + CBT = most effective)

85
Q

Drugs indicated for GAD?

A

SSRIs including escitalopram, paraoxetine and sertraline

Buspirone

Quetiapine (2nd gen antipsychotic)

SNRIs

Diazepam and lorazepam

86
Q

Drugs indicated for OCD?

A

All SSRIs EXCEPT citalopram

Mirtazapine (NaSSA)

CAs/TCAs

MAOIs

87
Q

Drugs indicated for PTSD?

A

Certain SSRIs:
Fluoxetine
Paraoxetine
Sertraline

Mirtazapine (NaSSA)

Risperidone (2nd gen antipsychotic)

SNRI: venlaxafine (not duloxetine)

CAs/TCAs

MAOI

88
Q

Drugs indicated for panic disorder?

A

SSRIs
SNRI: venlafaxine (not duloxetine)
CAs/TCAs
Benzos

89
Q

Drugs indicated for social anxiety?

A

SSRIs
SNRI: venlafaxine (not duloxetine)
MAOIs
Clonazepam

90
Q

In which disorders is duloxetine indicated?

Panic disorder
GAD
Social anxiety
OCD
PTSD
A

GAD only

91
Q

In which disorders is clonazepam indicated?

Panic disorder
GAD
Social anxiety
OCD
PTSD
A

Panic and social anxiety

92
Q

In which disorders is venlafaxine indicated?

Panic disorder
GAD
Social anxiety
OCD
PTSD
A

All except OCD

93
Q

In which disorders are CAs/TCAs indicated?

Panic disorder
GAD
Social anxiety
OCD
PTSD
A

OCD and PTSD

94
Q

In which disorders are MAOIs indicated?

Panic disorder
GAD
Social anxiety
OCD
PTSD
A

All except GAD (but not first line)

95
Q

What is the pathophys present in ADHD?

A

Decrease in NE release
Decreased dopamine functionality

= hyperactivity, inattention, impulsivity

96
Q

What is the first-line treatment of ADHD?

A

Stimulant medications:
Amphetamines
Synthetics

97
Q

What is the second-line treatment of ADHD?

A

Non-stimulant meds:
Atomoxetine
Bupropion
(others)

98
Q

What is the MOA of the synthetic medications used in ADHD?

A

Inhibition of PRE-synaptic dopamine transporter

Inhibition of PRE-synaptic NE transporter

= inhibited reuptake of these neurotransmitters

99
Q

What is the MOA of the synthetic medications used in ADHD?

A

Inhibit reuptake of dopamine and NE via inhibition of pre-synaptic transporters

100
Q

What is the MOA of amphetamine agents used in ADHD?

A

Two-fold:

  • Inhibit reuptake of dopamine and NE via inhibition of pre-synaptic transporters
  • Displacement of dopamine and NE from storage vesicles; increases dopamine/NE release
101
Q

What occurs when amphetamine agents are used at too high a dose?

A

Worsening of ADHD symptoms

Can also cause euphoria, tachycardia, tics

102
Q

What are some common AE associated with ADHD stimulant drugs?

A
N/V/abx pain
HA
Possible weight loss, anorexia
Irritability
Tachycardia
Insomnia
Dry mouth

Can also lower seizure threshold and THOROUGHLY SCREEN pts for bipolar disorder! Good way to trigger a manic episode.

103
Q

You have a 10 year old patient who you have diagnosed with ADHD. His mother shows concern about her child potentially developing a substance use disorder. What can you tell her?

A

Untreated ADHD carries a higher risk of substance use disorder than appropriate use of ADHD with careful monitoring

104
Q

What are the non-stimulant medications used in ADHD?

A

Atomoxetine

a-adrenergic agonists

105
Q

What is the MOA of atomoxetine?

A

NE reuptake inhibition