Behavioral Med Drugs Flashcards
What is the prototypical low-potency first gen antipsychotic?
Chlorpromazine (Thorazine)
What is the prototypical high-potency first gen antipsychotic?
Haloperidol (Haldol)
What are 5 examples of second gen antipsychotics?
Clozapine Quetiapine (Seroquel) Risperidone Ziprasidone (Geodon) Aripirazole (Abilify) - this has a unique MOA
(Olanzapine is used frequently in Rosh questions)
What is the therapeutic MOA of first gen antipsychotics?
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)
What are other receptor (non-therapeutic targets) effects of first generation antipsychotics?
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
First gen antipsychotics are indicated for what in schizophrenia? Why?
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.
What is the pathophys/etiology of positive symptoms in schizophrenia?
Excess of dopamine in the mesolimbic system
What is the pathophys/etiology of negative symptoms in schizophrenia?
Deficiency of dopamine in the mesocortical system, secondary to excess serotonin
(or secondary to dopamine blocking caused by 1st gen antispsychotics/other drugs)
When an first gen antipsychotic drug acts on the nigrostriatal dopamine pathway, what occurs?
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)
When an first gen antipsychotic drug acts on the tuberoinfundibular dopamine pathway, what occurs?
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
What is the therapeutic MOA of second-gen antipsychotics?
Weakly antagonize D2 receptors in the mesolimbic dopamine pathway (or weakly agonize)
Antagonize serotonin receptors in mesocortical system
Other than mesolimbic and mesocortical effects, what are some actions of second gen antipsychotics?
Nigrostriatal pathway:
Promotes dopamine release to compete with D2 block
Tuberoinfundibular pathway:
5Ht-stimulated prolactin release is blocked
Which antipsychotic class is likely to cause the MOST sedation?
Low-potency first generation (chlorpromazine)
All antipsychotics have the potential to cause some sedation
Which antipsychotic class is most likely to cause seizures?
First gen (haldol and chlorpromazine) AND clozapine (2nd gen)
What antipsychotic class is most likely to cause EPS symptoms?
First generation (especially high potency)
Also, risperidone (dose-dependent)
If a patient, who is otherwise stable on their antipsychotic medication, exhibits laryngospasm, what should be done?
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.
If a patient, who is otherwise stable on their antipsychotic medication, exhibits repetitive lip smacking, what should be done?
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.
Which antipsychotic has the highest risk of prolonged QT interval?
*ZZ:
Ziprasidone and cloZapine
You have a patient with obesity who requires an antipsychotic. She reports no cardiac history. Which might be a good choice?
Aripiprazole has less potential for weight gain and less sedation.
Ziprasidone also has less potential for weight gain.
Which second gen antipsychotics are most associated with weight gain?
Clozapine
Risperdone, but this is a dose-dependent effect
Your patient tells you she has a history of “heart problems”. When considering an antipsychotic for her, what would be some considerations?
Ziprasidone and iloperidone have highest risk of QT prolongation.
Your patient has diabes and requires an antipsychotic medication. What are some considerations?
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
Which antipsychotic agents are most likely to cause EPS symptoms?
High-potency first gen (haloperidol)
Which antipsychotic agents are most likely to cause anti-HAM effects?
Low potency first generation (chlorpromazine)
anti-HAM = histamine, a1, and muscarinic antagonism-related side effects + seizures
What is a miscellaneous adverse effect of quetiapine?
Formation of cataracts
What are some important considerations with the drug clozapine?
- 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!
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?
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.
What kind of regular screening should be performed on a patient who is taking a second gen antipsychotic?
- Emergence of movement disorders
- Weight/waist circumference
Metabolic screening:
- ** FBG
- ** HbA1c
- ** FLP
- plus stuff like response to tx, symptom profile, overall health, interactions, etc
You are prescribing your patient a first gen antipsychotic. What might you consider prescribing alongside the antipsychotic?
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. :/ )
Which antipsychotic should be avoided IV?
Haloperidol, due to increased risk for QT prolongation. Use it IM instead.
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.
Haloperidol (1st gen antipsychotic)
Risperidone (2nd gen antipsychotic)
Benzodiazepines (tranquilizer)
Lithium (mood stabilizer)
Valproate (anti-convulsant used for mood stabilization)
What are some drugs that can be used for a patient with bipolar disorder who is experiencing an acute mania (without signs of psychosis)?
2nd gen antipsychotics (minus clozapine)
Plus:
- Lithium
- Carbamazepine
What are some medications that can be used for maintenance in a patient with bipolar disorder?
Some 2nd gen antipsychotics (asenapine, clozapine, olanzapine, quetiapine)
Plus:
- Lithium
- Valproate
- Carbamazepine
- Lamotrigine
What is a drug that might be used for maintenance of bipolar disorder but NOT for an acute mania?
Lamotrigine
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?
Valproate
What is a drug that can be used for maintenance, acute mania, and acute mania with psychosis for a patient with bipolar disorder?
Lithium
What is the cause of the adverse effects associated with lithium?
- Reduced 2nd messengers (IP3/DAG)
- Inhibition of adenyl cyclase
- Uncoupling of G proteins (vasopression and TSH receptors)
What is the first line treatment of bipolar 1, and what is its MOA?
- Lithium
- MOA:
- Enhancement of serotonin action via facilitation of release
- Attenuation of NE
What must be screened in a patient taking lithium?
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
What are some adverse effects of lithium?
- 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
What are some signs of lithium toxicity?
- Coarse tremor
- Seizure
- Arrhythmia
- Vomiting and/or diarrhea
- Tubular necrosis
What are some drugs/conditions that INCREASE lithium serum concentration?
- Thiazide diuretics
- NSAIDs
- ACEIs
- Dehydration
- Reduced Na intake
- Decreased GFR
- Postpartum state (vs pregnancy)