Psychopharmacology Discussion Thread

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I will be posting important questions from Psychopharmacology section here .

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[Admin]

7. Which of the following statement is FALSE:

(a) Long term Thorazine use can cause reversible blue gray discoloration of skin areas exposed to sunlight
(b) Thorazine can cause benign pigmentation of eye
(c) Irreversible retinal pigmentation is associated with Thioridazine >1000mg/day
(d) Do not use emetics in suspected case of typical antipsychotic overdose
(e) Molindone is the most epileptogenic of all all typical antipsychotics
(f) All are correct
(g) All are wrong

e) low potency antipsychotics such as chlorpromazine are most epileptogenic....molindone is a mid-potency typical anti-psychotic hence above statement should be false

Correct

Ans: (E) Molindone is the most epileptogenic of all all typical antipsychotics
DRAs may lower seizure threshold. Molindone is the least epileptogenic of DRA drugs.


Other options are correct:
- Do not use emetics in suspected case of typical antipsychotic overdose.Reason: antiemetic action of DRAs inhibit their efficacy.
- Long term Chlorpromazine use: blue gray discoloration of skin areas exposed to sunlight. Reversible after discontinuation
- Chlorpromazine can cause benign pigmentation of eye (whitish brown granular deposit in anterior lens & posterior cornea- on slit lamp exam)
- Thioridazine maximal recommended dosage is 800 mg/day
Reason: Irreversible retinal pigmentation is associated with Thioridazine use >1000 mg/day. Earliest symptom: nocturnal confusion related to difficulty in night vision.

[Admin]

8. Which of the following is FALSE regarding Antipsychotics:

(a) Cigarette smoking can reduce the plasma concentration of antipsychotic agents
(b) ACE inhibitors added to antipsychotics can result in postural intolerance
(c) Caffeinated beverages can possibly diminish the antipsychotic effects by forming a precipitate
(d) Disulfiram can decrease the antipsychotic concentration
(e) Antipsychotics can decrease the warfarin levels


e) as phenothiazines enhances the action of oral anticoagulants but chlorpromazine decreases their effect hence i m not sure

Ans: (d) Disulfiram can decrease the antipsychotic concentration.
Correct statement: Disulfiram can increase the antipsychotic concentration- by impairing the antipsychotic metabolism.
Source: Kaplan & Sadock's Table 36.18-5


- DRAs + Warfarin= decreased level of warfarin= decreased bleeding time
Read:
* Gen Hosp Psychiatry. 2011 May-Jun;33(3):302
* J Clin Psychiatry. 2010;71(6):689-98

- Cigarette smoking can reduce the plasma concentration of antipsychotic agents
Mechanism: Induction of microsomal enzymes.
Note: Smoking cessation (commonly when patient's are hospitalized) can result in rise in plasma concentration of antipsychotics.

- ACE inhibitors added to antipsychotics can result in postural intolerance:
Mechanism: Additive hypotensive crisis

- Caffeinated beverages can possibly diminish the antipsychotic effects by forming a precipitate:
correct

[Admin]

Thanks Adisuper and P450 for participation.

Please do not hesitate to post if you don't agree with my answers.
We all are here to learn from each other

Everyone is encouraged to participate here!!

[adisuper]

9. Which of the following is FALSE regarding "Transition of Antipsychotics":

(a) Transition from Clozapine to Olanzapine is safe in terms of cholinergc rebound.
(b) Transition from Olanzapine to Risperidone is safe in terms of cholinergc rebound.
(c) Transition from Clozapine to Ziprasidone is not safe in terms of cholinergc rebound
(d) All are correct
(e) All are wrong

b) olanzapine has moderate affinity for muscarinic receptors while risperidone do not have anticholinergic axns....hence sudden transition from olanzapine to risperidone could result in cholinergic rebound
but i think that option a is also false as clozapine having strong anticholinergic properties should never be transitioned abruptly with other anti-psychotic unless agranulocytosis develops.
option c is correct


10. Which of the following Atypical Antipsychotic have LEAST RISK for EPS (Extra Pyramidal Symptoms)

(a) Olanzapine
(b) Risperidone
(c) Clozapine
(d) Quetiapine
(e) Aripiprazole

clozapine has least risk of EPS follwed by quitiapine
clozapine least chances of causing tardive dyskinesia and is infact used sometimes to reduce dyskinesia symptoms

[Admin]

9. Which of the following is FALSE regarding "Transition of Antipsychotics":

(a) Transition from Clozapine to Olanzapine is safe in terms of cholinergc rebound.
(b) Transition from Olanzapine to Risperidone is safe in terms of cholinergc rebound.
(c) Transition from Clozapine to Ziprasidone is not safe in terms of cholinergc rebound
(d) All are correct
(e) All are wrong

b) olanzapine has moderate affinity for muscarinic receptors while risperidone do not have anticholinergic axns....hence sudden transition from olanzapine to risperidone could result in cholinergic rebound
but i think that option a is also false as clozapine having strong anticholinergic properties should never be transitioned abruptly with other anti-psychotic unless agranulocytosis develops.
option c is correct

CORRECT

Ans: (b) Transition from Olanzapine to Risperidone is safe in terms of cholinergc rebound.

Explanation:

• Clozapine & Olanzapine have anticholinergic activity, and transition from one to other can usually be accomplished with little risk of cholinergic rebound.
• Transition from risperidone to olanzapine- best accomplished by tapering the risperidone off over 3 weeks and simultaneously beginning olanzapine at 10 mg/day.
• Risperidone, Quetiapine and Ziprasidone lack anticholinergic effects. Abrupt transition from DRA/Olanzapine/Clozapine to either of these agents can cause cholinergic rebound (excessive salivation, nausea, vomiting & diarrhea).
• Risk of cholinergic rebound mitigated by- initially augmenting risperidone/quetiapine/ziprasidone with anticholinergic drug, which is then tapered off slowly.

[Admin]

10. Which of the following Atypical Antipsychotic have LEAST RISK for EPS (Extra Pyramidal Symptoms)

(a) Olanzapine
(b) Risperidone
(c) Clozapine
(d) Quetiapine
(e) Aripiprazole

clozapine has least risk of EPS follwed by quitiapine
clozapine least chances of causing tardive dyskinesia and is infact used sometimes to reduce dyskinesia symptoms

CORRECT


EPS Risk by class of medication (increases from 1-5):
1. Quetiapine/Clozapine
2. Aripiprazole/Olanzapine/Ziprasidone
3. Paliperidone/Risperidone
4. Low-potency conventional neuroleptic
5. High-potency conventional neuroleptic (20-40%)

Interesting History of EPS & Antipsychotic:

Within the first few years after chlorpromazine began to be used to treat psychosis, it was observed that it could cause many kinds of neurologic reactions that resembled those seen in idiopathic Parkinson's disease. These reactions were termed "extrapyramidal side effects" (EPS) because of their resemblance to the signs of Parkinson's disease, which were associated with degeneration of the dopamine nerve tracks located in the extrapyramidal region of the central nervous system. Eventually this association of dopamine loss, antipsychotics, and parkinsonism became a central part of the dopamine hypothesis of schizophrenia. Unfortunately, this association was also used to support the hypothesis that EPS were absolutely necessary for antipsychotic efficacy--hence the term "neuroleptic" rather than "antipsychotic." This theory, now discredited, was used to justify the practice of inducing EPS as a means to gauge whether an antipsychotic would be effective. The demonstration that clozapine, an antipsychotic virtually devoid of EPS, has better efficacy for psychosis than any other "neuroleptic" disproved the theory that EPS were fundamentally linked to efficacy. Because the idea of a relationship between EPS and efficacy was so ingrained in clinical practice, clozapine was called "atypical." Our understanding of the relationship between EPS and antipsychotic response has come full circle. With the introduction of clozapine and other newer antipsychotics, it has become clear that EPS are harmful and serve no beneficial purpose.

[adisuper]

Q16. Which of the following SSRI is least likely to complicate treatment due to drug interactions?

(a) Fluoxetine
(b) Fluvoxamine
(c) Paroxetine
(d) Citalopram

d) Citalopram is least likely as it has lower degree of protien binding and hence protien binding interactions shouldn't be a problem. also it is just a modest inhibitor of cyp2d6 while weak inhibitor of cyp1a2 and cyp2c19 with no axn on other isozymes


Q.17: Match the following drug interactions with responsible CYP450 enzyme:

(1) Fluvoxamine + Theophylline =Raises Theophyline
(2) Fluvoxamine + Cisapride = Raised QT Interval
(3) Nefazodone + Alprazolam = Raises Alprazolam
(4) TCAs + SSRIs =Raises TCAs
(5) Fluozetine + Triazolam = Raises Triazolam
(6) Carbamazepine Autoinduction
(7) Imipramine + Smoking= Decreases Imipramine level

(a) CYP450 1A2
(b) CYP450 2D6
(c) CYP450 3A4

1) a, 2) c, 3) c, 4) b, 5) c, 6) c, 7) a

[adisuper]

Q18. Which of the following Statement is FALSE regarding Fluoxetine?

(a) Fluoxetine use during pregnancy is not associated with decrease in global IQ in children
(b) Only Fluoxetine is FDA approved for use as an antidepressant in children
(c) Most common adverse effect associated with long term use is sexual dysfunction
(d) Pt on Fluoxetine gain weight initially followed by weight loss.
(e) Fluoxetine can change the duration of menstrual period by more than 4 days

d) pts. on SSRI initially loose some weight but they then regain wt. and may have significant wt. gain in subsequent months

only fluoxetine is approved as an antidepressant in children and fluvoxamine for ocd in children
not sure about option d though

[Admin]

Q16. Which of the following SSRI is least likely to complicate treatment due to drug interactions?

(a) Fluoxetine
(b) Fluvoxamine
(c) Paroxetine
(d) Citalopram

d) Citalopram is least likely as it has lower degree of protien binding and hence protien binding interactions shouldn't be a problem. also it is just a modest inhibitor of cyp2d6 while weak inhibitor of cyp1a2 and cyp2c19 with no axn on other isozymes

Correct. Ans- Citalopram.

Note: Sertraline, Citalopram, and Escitalopram are least likely to complicate treatment because of interactions.

[Admin]

Q.17: Match the following drug interactions with responsible CYP450 enzyme:

(1) Fluvoxamine + Theophylline =Raises Theophyline
(2) Fluvoxamine + Cisapride = Raised QT Interval
(3) Nefazodone + Alprazolam = Raises Alprazolam
(4) TCAs + SSRIs =Raises TCAs
(5) Fluoxetine + Triazolam = Raises Triazolam
(6) Carbamazepine Autoinduction
(7) Imipramine + Smoking= Decreases Imipramine level

(a) CYP450 1A2
(b) CYP450 2D6
(c) CYP450 3A4

1) a, 2) c, 3) c, 4) b, 5) c, 6) c, 7) a

Perfect answer Adisuper.
Ans:
(1) Fluvoxamine + Theophylline =Raises Theophyline ---> 1A2
(2) Fluvoxamine + Cisapride = Raised QT Interval ---> 3A4
(3) Nefazodone + Alprazolam = Raises Alprazolam ----> 3A4
(4) TCAs + SSRIs =Raises TCAs --->
(5) Fluoxetine + Triazolam = Raises Triazolam ----> 3A4
(6) Carbamazepine Autoinduction ---> 3A4
(7) Imipramine + Smoking= Decreases Imipramine level --->1A2

Read this thread for more details ---> http://bit.ly/zn3Dpx

[Admin]

Q18. Which of the following Statement is FALSE regarding Fluoxetine?

(a) Fluoxetine use during pregnancy is not associated with decrease in global IQ in children
(b) Only Fluoxetine is FDA approved for use as an antidepressant in children
(c) Most common adverse effect associated with long term use is sexual dysfunction
(d) Pt on Fluoxetine gain weight initially followed by weight loss.
(e) Fluoxetine can change the duration of menstrual period by more than 4 days

d) pts. on SSRI initially loose some weight but they then regain wt. and may have significant wt. gain in subsequent months

only fluoxetine is approved as an antidepressant in children and fluvoxamine for ocd in children
not sure about option d though

Ans: D

Fluoxetine: Must Know Facts

- Studies that have followed children into their early school years have failed to find any perinatal complications, congenital fetal anomalies, decreases in global intelligence quotient (IQ), language delays, or specific behavioral problems attributable to the use of fluoxetine during pregnancy.
- Only Fluoxetine is FDA approved for use as an antidepressant in children.
- Fluvoxamine and Sertraline have also been approved for treatment of pediatric OCD (ages 6 to 17).
- All SSRIs cause sexual dysfunction, and it is the most common adverse effect of SSRIs associated with long-term treatment- estimated incidence: 50-80%.
- Initial anorexia can also occur and is most common with fluoxetine.
- SSRI-induced appetite and weight loss begin as soon as the drug is taken and peak at 20 weeks, after which weight often returns to baseline.
- An observation of unclear significance was that fluoxetine was associated with changing the duration of the menstrual period by more than 4 days, either lengthening or shortening.

[Admin]

Thanks for participating Adisuper !!

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