Dose Equivalents / Equivalency / Comparison for Antidepressants and Second-Generation Antipsychotics

[DoctorMussyWasHere]

MODERATOR'S NOTE: 

 

Because antipsychotic drugs hit many different receptors at different strengths, linear ratios of equivalence are close to impossible and the recommended equivalence is only an approximation. Thus, we recommend that members only use AP switching as a last ditch effort to get off their drug. Members should first try tapering their current AP very slowly (cuts of less than 5% per month if necessary) or holding the dose to stabilize for a long period if withdrawal symptoms are too intense. 

 

If a crossover to another drug is attempted, the member should find the minimum dose that is within range of the recommended equivalency which doesn't worsen their symptoms (or does so minimally). The crossover between drugs should be slow and symptom-based (gradual enough to avoid a worsening of symptoms). 

 

-------------------------------------------

 

A potentially useful resource: Dose Equivalents for Second-Generation Antipsychotics: The Minimum Effective Dose Method

The article includes a huge table of equivalent doses and studies. Here's the dose data extracted:

 

 

Table 2.

Minimum Effective Doses of Second-Generation Antipsychotic Drugs and Dose Equivalents

Drug	Minimum Effective Dose	OLA 1 mg Equivalent	RIS 1 mg Equivalent	HAL 1 mg Equivalent	CPZ 100 mg Equivalent
Amisulpride	−	−	−	−	−
Aripiprazole	10	1.33 (1)	5 (2.5)	2.5 (2.2)	4 (3.6)
Asenapine	10	1.33 (1)	5 (2.5)	2.5 (2.2)	4 (3.6)
Clozapine	300?	40 (30)	150 (75)	75 (67)	120 (107)
Haloperidol	4 (4.5)	0.53 (0.45)	2 (1.13)	1	1.6
Iloperidone	8a (12)	1.07a (1.2)	4a (3)	2a (2.7)	3.2a (4.3)
Lurasidone	40	5,33 (4)	20 (10)	10 (8.9)	16 (14.2)
Olanzapine	7.5 (10)	1	3.75 (2.5)	1.88 (2.2)	3 (3.6)
Paliperidone	3 (6)	0.4 (0.6)	1.5 (1.5)	0.75 (1.3)	1.2 (2.1)
Quetiapine	150 (250)	20 (25)	75 (62.5)	37.5 (55.6)	60 (88.9)
Risperidone	2 (4)	0.27 (0.4)	1	0.5 (0.9)	0.8 (1.4)
Sertindole	12 (16)	1.60 (1.6)	6 (4)	3 (3.6)	4.8 (5.7)
Ziprasidone	40 (80)	5.33 (8)	20 (20)	10 (17.8)	16 (28.4)
Zotepine	−	−	−	−	−

 

Edited July 24, 2021 by DataGuy
Replacing minimal effective dose table with dose equivalency table

[Altostrata]

J Affect Disord. 2015 Jul 15;180:179-84. doi: 10.1016/j.jad.2015.03.021. Epub 2015 Mar 31.

Dose equivalents of antidepressants: Evidence-based recommendations from randomized controlled trials.

Hayasaka Y1, Purgato M2, Magni LR3, Ogawa Y1, Takeshima N1, Cipriani A4, Barbui C2, Leucht S5, Furukawa TA1.

 

Abstract at https://www.ncbi.nlm.nih.gov/pubmed/25911132 Free full text at https://www.sciencedirect.com/science/article/pii/S0165032715001512

 

BACKGROUND:

Dose equivalence of antidepressants is critically important for clinical practice and for research. There are several methods to define and calculate dose equivalence but for antidepressants, only daily defined dose and consensus methods have been applied to date. The purpose of the present study is to examine dose equivalence of antidepressants by a less arbitrary and more systematic method.

 

METHODS:

We used data from all randomized, double-blind, flexible-dose trials comparing fluoxetine or paroxetine as standard drugs with any other active antidepressants as monotherapy in the acute phase treatment of unipolar depression. We calculated the ratio of the mean doses for each study and weighted it by the total sample size to find the weighted mean ratio for each drug, which was then used to define the drug׳s dosage equivalent to fluoxetine 40mg/d.

 

RESULTS:

We included 83 studies (14 131 participants). In the primary analysis,

 

fluoxetine 40mg/day was equivalent to

paroxetine dosage of 34.0mg/day,

agomelatine 53.2mg/day,

amitriptyline, 122.3mg/day,

bupropion 348.5mg/day,

clomipramine 116.1mg/day,

desipramine 196.3mg/day,

dothiepin 154.8mg/day,

doxepin 140.1mg/day,

escitalopram 18.0mg/day,

fluvoxamine 143.3mg/day,

imipramine 137.2mg/day,

lofepramine 250.2mg/day,

maprotiline 118.0mg/day,

mianserin, 101.1mg/day,

mirtazapine 50.9mg/day,

moclobemide 575.2mg/day,

nefazodone 535.2mg/day,

nortriptyline 100.9mg/day,

reboxetine 11.5mg/day,

sertraline 98.5mg/day,

trazodone 401.4mg/day, and

venlafaxine 149.4mg/day.

 

Sensitivity analyses corroborated the results except for doxepin.

 

LIMITATIONS:

The number of studies for some drugs was small. The current method assumes dose response relationship of antidepressants.

 

CONCLUSIONS:

Our findings can be useful for clinicians when they switch antidepressants and for researchers when they compare various antidepressants in their research.

 

Edited August 1, 2020 by ChessieCat
updated link/CC coloured and spaced drug and doses

[Altostrata]

ADMIN NOTE: Many clinicians believe dosage may be reduced when acute phase (dramatic symptoms) is over. We recommend a very, very gradual reduction to avoid destabilization that might send you back to the acute phase dosage.

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Schizophr Res. 2018 Mar;193:23-28. doi: 10.1016/j.schres.2017.07.033. Epub 2017 Jul 21.

Dose equivalents for second generation long-acting injectable antipsychotics: The minimum effective dose method.

Rothe PH1, Heres S2, Leucht S2.

 

Abstract at https://www.ncbi.nlm.nih.gov/pubmed/28735640

 

BACKGROUND:

The concept of dose equivalence of depot medication is important for many scientific and clinical purposes.

 

METHODS:

A systematic literature search on four second-generation antipsychotics available as long-acting injectable drugs and haloperidol was conducted. We used the minimum effective dose method which is based on randomized fixed dose studies where the smallest dose which was significantly more efficacious than placebo in the primary outcome was declared as minimum effective dose. We calculated equivalent doses from acute phase studies but we also reported the minimum effective doses found in relapse prevention studies.

 

RESULTS:

The acute phase minimum effective doses/olanzapine equivalents were: aripiprazole lauroxil 441mg (300mg aripiprazole)/4wks/0.71; aripiprazole 400mg/4weeks/0.95 (aripiprazole maintena); paliperidone palmitate 25mg/4weeks/0,06; risperidone 25mg/2weeks/0,12; RBP-7000 90mg/4weeks/0,21; olanzapine 210mg/2weeks/1.

 

CONCLUSIONS:

The minimum effective dose method is an operationalized and evidence-based approach for determining antipsychotic dose equivalence which can also be applied to long-acting injectable formulations. Doses may not have been chosen low enough to find the truly minimum effective dose. Comparisons with other methods will be necessary to come to ultimate conclusions.

Edited May 17, 2018 by Altostrata
updated

[Altostrata]

ADMIN NOTE This is useful because it gives dosage ranges for these drugs.

---

 

https://psychopharmacologyinstitute.com/antipsychotics/long-acting-injectable-antipsychotics-a-practical-guide-for-prescribers/

 

Long-Acting Injectable Antipsychotics: A Practical Guide for Prescribers

 

Author: Flavio Guzman, MD
Last updated: February 10, 2018
Competing interests: none

 

This article summarizes the most clinically relevant features of long-acting injectable antipsychotics (LAIs, previously known as depot antipsychotics). We discuss general concepts as well as key prescribing facts of individual agents.

The guide also includes two new formulations: aripiprazole lauroxil (Aristada) and 3-month paliperidone palmitate (Invega Trinza).

Advantages and disadvantages of long-acting antipsychotics

Brissos and colleagues [1] reviewed the role of long-acting injectables in schizophrenia. They summarized the key advantages and disadvantages of LAIs in clinical practice.

Potential advantages

• Early identification of non-adherence
• Providing a mechanism for monitoring adherence with injections
• No need to remember to take medication every day
• Regular interactions between patient and medical staff
• Reduced relapse frequency and rehospitalization rates
• Clear attribution of the cause of relapse or non-response, discriminating between non adherence or lack
  of response
• Reduce the risk of accidental or deliberated overdose
• Treating patients with more stable plasma concentrations than oral medications
• Avoidance of first-pass metabolism – better relationship between dose and blood level of drug
• Lower and less frequent peak plasma level – reduced side effects

Potential disadvantages

• Slow dose titration
• Longer time to achieve steady state levels
• Less flexibility of dose adjustment
• Delayed disappearance of distressing and/or severe side effects
• Pain at the injection site can occur, and leakage into the subcutaneous tissue and/or the skin may cause irritation and lesions (especially for oily long-acting injectable)
• Burden of frequent travel to outpatient clinics or home visits by community nurses for their administration
• Risperidone long-acting injectable needs refrigeration, which may be cumbersome in some latitudes
• Perception of stigma

Clinical questions answered

Castillo and Stroup [2] reviewed the effectiveness of LAIs and addressed the following questions:

Who should receive LAIs?

Consider LAIs for patients with recent-onset schizophrenia and those with risk factors for medication non-adherence: history of non-adherence, severe symptoms, comorbid substance use, cognitive impairment, ambivalence or negative attitudes towards medications, and poor insight.

Are the newer LAIs more effective?

The effectiveness of newer LAIs (aripiprazole, olanzapine, paliperidone and risperidone) and older LAIs (haloperidol,fluphenazine, flupenthixol) is similar.

Tables summarizing individual agents

First-generation antipsychotics available as long-acting injectable medications

 

Drug	Starting dose (mg)	Maintenance dose (mg)
Haloperidol decanoate	50	50–200 every 3–4 weeks
Fluphenazine decanoate	12.5	12.5 – 50 every 2–3 weeks
Flupenthixol decanoate	20	50–300 every 2–4 weeks
Zuclopenthixol decanoate	100	200–500 every 1–4 weeks

Second-generation antipsychotics available as long-acting injectable medications

Drug (Brand name)	Manufacturer	Available formulations	Injection interval	Comments
Aripiprazole monohydrate (Abilify Mantenna)	Otsuka/ Lundbeck	300,400 mg vials, prefilled syringes	400 mg once/month	Requires a period of 2 weeks of overlap with oral aripiprazole.
Aripiprazole lauroxil (Aristada)	Alkermes	441, 662, 882 mg prefilled syringes	441–882 mg once/month 882 mg q 6 weeks	The 882 mg dose can be administered every 6 weeks. Requires a period of 3 weeks of overlap with oral aripiprazole.
Olanzapine pamoate (Zyprexa Relprevv)	Lilly	210, 300, 405 mg vials	150–300 mg q2 weeks 300–405 mg once/month	Requires monitoring post injection (3 hours)
Paliperidone palmitate (Invega Sustenna, Xeplion)	Janssen	39,78,117,156 or 234 mg prefilled syringes	117 mg once/month	Oral supplementation not necessary.
Paliperidone palmitate (Invega Trinza)	Janssen	273, 410, 546, 819 mg prefilled syringes	410 mg q3 months	Use in patients already treated with Invega Sustenna
Risperidone microspheres   (Risperdal Consta)	Janssen	12.5, 25, 37.5 or 50 mg vials	25 mg q2 weeks	Requires a period of 3 weeks of overlap with oral risperidone

Practical considerations

Abilify Mantenna

• Aripiprazole monohydrate requires a period of overlap of 2 weeks with oral aripiprazole.
• Available as a lyophilized powder which needs to be reconstituted.

See full prescribing information (PDF)

Aristada

• Aripiprazole lauroxil requires a period of overlap of 3 weeks with oral aripiprazole.
• Available as a prefilled syringe that does not require reconstitution.

See full prescribing information (PDF)

Highlights of prescribing information

Zyprexa Relprevv

• Olanzapine pamoate does not need overlap with oral olanzapine.
• It has a small risk of post-injection syndrome (0.07% of injections):
  • Symptoms include sedation, confusion, agitation, anxiety, aggressiveness, dizziness, ataxia and extrapyramidal symptoms
  • This risk limits use olanzapine pamoate use
  • After injection, the patient must be monitored for three hours by a healthcare professional
  • In the US, prescribers who administer Zyprexa Relprevv must enroll in a national registry that documents the incidence of this adverse effect

See full prescribing information (PDF)

Invega Sustenna

• Paliperidone palmitate does not need overlap with oral paliperidone.
• Requires two separate loading dose injections during the first week.

See full prescribing information (PDF)

Invega Trinza

• The 3-month paliperidone palmitate (PPM–3) formulation can only be used if the patient has been receiving 1-month paliperidone palmitate injections for at least 4 months.
• It is administered 4 times a year, providing the longest interval of any approved LAI.

See full prescribing information (PDF)

Risperdal Consta

• Risperidone microspheres requires a period of overlap of 3 weeks with oral risperidone.
• It has a 2-week dosing interval.

See full prescribing information (PDF)

Acknowledgements: Thanks to Dr. Leslie Lundt for correcting an earlier version of this article.

References

1. Brissos, S., Veguilla, M. R., Taylor, D., & Balanzá-Martinez, V. (2014). The role of long-acting injectable antipsychotics in schizophrenia: a critical appraisal. Therapeutic advances in psychopharmacology, 2045125314540297. 
2. Castillo, E. G., & Stroup, T. S. (2015). Effectiveness of long-acting injectable antipsychotics: a clinical perspective. Evidence Based Mental Health, ebmental–2015. 
3. Gopalakrishna, G., Aggarwal, A., & Lauriello, J. (2013). Long-acting injectable aripiprazole: how might it fit in our tool box?. Clinical schizophrenia & related psychoses, 7(2), 87-92.
4. Citrome, L. (2015). Aripiprazole long-acting injectable formulations for schizophrenia: aripiprazole monohydrate and aripiprazole lauroxil.Expert review of clinical pharmacology, 1-18.

[bubbles]

On 5/9/2018 at 5:35 AM, Altostrata said:

J Affect Disord. 2015 Jul 15;180:179-84. doi: 10.1016/j.jad.2015.03.021. Epub 2015 Mar 31.

Dose equivalents of antidepressants: Evidence-based recommendations from randomized controlled trials.

Hayasaka Y1, Purgato M2, Magni LR3, Ogawa Y1, Takeshima N1, Cipriani A4, Barbui C2, Leucht S5, Furukawa TA1.

 

I wonder if the link to this article further up in the thread is broken. I found it here: https://www.sciencedirect.com/science/article/pii/S0165032715001512

[Altostrata]

The link works fine for me, bubbles. I have added your link to the post as well.

[bubbles]

Thanks Alto. The first "full text" link in that post is taking me to the antipsychotic article, not the antidepressant article.

Cheers!

[Altostrata]

Thanks, bubbles, correction made.

[arwilliams]

@DoctorMussyWasHere do you know of these dosages hold true between Zyprexa and seroquel for sedation?  I have crazy insomnia when stopping 2.5mg of Zyprexa.

 

If 1mg of Zyprexa is 75mg of seroquel then well Seroquel is going to be a lot easier to taper with or with out a precision scale.

[Altostrata]

ar, if you're physiologically dependent on Zyprexa, it's not a sure thing that you can swap in any amount of Seroquel.

 

The equivalencies above are from medical journal sources, but they're still approximate.

[DoctorMussyWasHere]

Hi arwilliams,

The chart is a resource I found online, and posted here, and I'm not intimately familiar with it

beyond what I recall from that time, which is to say, not much.

 

I can comment on Seroquel somewhat, but not on switching to it.

Altostrata has replied with that advice.

 

The Seroquel is something my "care", Tiggy is currently on.

She operates mostly independently of my advice these days,

which is to say I advised against it after researching it fairly thoroughly.

 

It's reportedly an excellent sedative, and she has confirmed that.

She says she has wobbly legs between taking it and falling asleep,

which is the sort of news that conversely keeps me awake.

 

 

 

As for the bad, it is apparently extremely problematic to be on, and one of the hardest to withdraw from,

for a reason which I suppose could be called interesting, unless you're the one on the drug, or trying to support someone.

 

The Seroquel leg of a study comparing various antipsychotics (aripiprazole (Abilify), olanzapine (Zyprexa), quetiapine (Seroquel) and risperidone (Risperdal))

had to be cancelled and scrapped completely because the patients in that segment developed adverse effects, at twice the rate of the other drugs. 

Ouch.. that's pretty bad

 

Also I saw that on David Healy's website, RXisk, that Seroquel (Quetiapine) had by far the highest number of people reporting problems.

(I think. I assume that I'm supposed to read it like that, below. @Healy I hope you don't mind me republishing that here.)

 

According to Healy:  "the Clozapine group of drugs that includes Zyprexa and Seroquel are noted as having some of the worse withdrawal problems."

 

 

-----------------------------

As for the reason, it's related to receptor binding. The drug blocks the receptor for a period.

Haloperidol blocks the receptors for around 38 minutes.

At the other end of the scale, Seroquel blocks them for about 16 seconds.

 

Initially the faster receptor unbinding translates into a preferred perceived effect by the person taking it

(I'm still looking for the reference to that)

 

The effect is a lower risk of extrapyramidal symptoms in the faster unbinding drug, but an increased receptor coverage,

which I guess would be the reason for the other adverse effects.

 

 

Philip Seeman is the researcher who, in 1974  - 20 years after the introduction of antipsychotics -

discovered the D2 receptor, and hence the part of the brain those drugs damage work on.

 

I'll finish off with a video with an animated sequence showing tight binding vs loose binding.

It appear as if Seeman * is demonstrating what being on a high dose looks like, but it was probably a technical glitch.

 

 

Seeman has researched Seroquel specifically.

The rapid unbinding from the receptor on the way down translates into extra instability, making it particularly hard to withdraw from.

 

He has researched the phenomenon of supersensitivity psychosis in antipsychotics in general,

which occurs upon withdrawal, and validates as "mental illness" in many people without prior disposition.

 

 

Rapid release of antipsychotic drugs from dopamine D2 receptors:

an explanation for low receptor occupancy and early clinical relapse upon withdraw... - PubMed - NCBI.

 

All roads to schizophrenia lead to dopamine supersensitivity and elevated dopamine D2(high) receptors. - PubMed - NCBI

 

 

Dopamine Antagonist Withdrawal Syndrome (DAAWS) | RxISK

 

Drug	SOS	Abuse	Addiction	Dependence	Intoxication	Total	%
Quetiapine Seroquel	809	367	253	211	1600	3240	34.49
Olanzapine Zyprexa	283	161	157	86	972	1659	17.66
Risperidone Risperdal	253	164	113	48	965	1543	16.43
Ziprasidone Geodon	199	42	128	110	389	868	9.24
Aripiprazole Abilify	114	61	27	13	670	885	9.42
Haloperidol	94	49	29	18	322	512	5.45
Paliperidone Invega	35	41	13	13	359	461	4.91
Chlorpromazine	30	9	2	1	78	120	1.28
Trifluoperazine	21	1	4	3	7	36	0.38
Tetrabenazine	5	5	0	1	27	38	0.40
Perphenazine	4	1	1	1	8	15	0.16
Iloperidone	2	0	0	0	12	14	0.15
Amisulpiride	0	0	0	0	0	0	0.00
Flupenthixol	0	0	0	0	0	0	0.00
Molindone	0	0	0	0	2	2	0.02
Pericyazine	0	0	0	0	0	0	0.00
Sulpiride	0	0	0	0	0	0	0.00
Zopetine	0	0	0	0	0	0	0.00
Clozapine
Zopetine	0	0	0	0	0	0	0.00
Clozapine
						9393

 

[DMV64]

On 2/15/2018 at 6:40 PM, DoctorMussyWasHere said:

Here's the dose data extracted

Thank you so much! This gives me hope I can get off Saphris which I am in the 1.5 small dose range and wondering how the heck I am going to make the 10% cuts??

[Altostrata]

DMV: Tips for tapering off asenapine (Saphris)

 

From psychopharmacologist Dr. Stephen M. Stahl's Neuroscience Education Institute (supported by pharmaceutical companies), here's a chart of

 

Receptor Binding Profiles of Atypical Antipsychotics:

Mechanism of Therapeutic Actions and Adverse Side Effects

 

http://cdn.neiglobal.com/content/practiceres/posters/50188_nei_009_bindings.pdf 

 

Citations:

Correll CU. Eur Psychiatry 2010;25(Suppl 2):S12-21. Nasrallah HA. Mol Psychiatry 2008;13(1):27-35.

National Institutes of Mental Health Psychoactive Drug Screening Program. Cited 2012 Aug. Available from: http://pdsp.med.unc.edu/indexR.html.

Stahl SM. Stahl’s essential psychopharmacology. 3rd ed. New York, NY: Cambridge University Press; 2008

 

(Thanks to JanCarol)

[DoctorMussyWasHere]

Note: The chart in the first post on this thread is more for referencing in relation to past prescribing, and generally not for any direction you might take in the future.

 

For starters, a switch always involves the effects of a different receptor binding profile in the new drug, which effectively means a fast titration upwards of certain receptors, and a fast withdrawal from others.

 

As a general rule, perhaps with rare exception, switching to another type of medication in a similar class is something a medical practitioner might attempt, but is generally not advised here.

[Altostrata]

Antidepressants Comparison Guide Most Commonly Prescribed from a US regional health insurance plan

 

gives rough dosage equivalents for some generic antidepressants.

 

https://www.healthalliance.org/media/Generics_antidepressants_comparison_chart.pdf

[JimH]

I read with interest the table of equivalencies from DoctorMussyWasHere at the top of the thread. I count 14 entries and wonder if what I saw is the complete list or there are other elements not listed here. Also could someone please redirect me to where I can find for each different AD the "Quit dose" where by this minuscule quantity the med has practically ceased any therapeutic effect and taperer could eventually jump when it is reached? Thank you.

[ChessieCat]

Therapeutic dose is an arbitrary term coined by the pharmaceutical companies.  The better term to use is lowest effective dose.

 

The jumping off dose is an individual thing.  People need to listen to their bodies and note their symptoms.  It isn't necessarily related to the drug they are taking.  We need to remember that it isn't cut and dried.  The brain needs to adapt to not getting as much of the drug and the amount of time it takes can vary between individuals and can be affected by many things.

 

Why taper paper: dose-occupancy curves

 

When to end the taper and jump to zero?  

 

Are there some who can't taper off no matter how slow they go?

 

Edited November 3, 2018 by ChessieCat

[JimH]

27 minutes ago, ChessieCat said:

..The jumping off dose is an individual thing...

Thanks. Could the above include the psychological aspect where taperers must go down to zero mg otherwise they don't feel healed?

[ChessieCat]

From what I've seen on SA and from my personal experience, I don't think that it is psychological (in the majority of cases).

 

Edited November 3, 2018 by ChessieCat

[Gridley]

 

1 hour ago, JimH said:

 "Quit dose" 

 

When to end the taper and jump to zero?

[ChessieCat]

This topic may be helpful:  are-we-there-yet-how-long-is-withdrawal-going-to-take

 

Edited August 1, 2020 by ChessieCat
updated link

[JimH]

Thanks Gridley!

 

Thanks ChessieCat for the long post. From the first few things I read I think brassmonkey has done a good job.

[Manny78]

What is the equivalent of abilify maintenance 400 mg injectable to abilify pill? 400mg maintenance injection is the equivalent of abilify 40mg pill? Thanks. 

 

[ChessieCat]

On 9/21/2018 at 6:43 AM, Altostrata said:

Antidepressants Comparison Guide Most Commonly Prescribed from a US regional health insurance plan

 

gives rough dosage equivalents for some generic antidepressants.

 

https://www.healthalliance.org/media/Generics_antidepressants_comparison_chart.pdf

 

The above link seems to be broken.  I found this:

 

https://www.healthalliance.org/Cms/Media?uri=https%3A%2F%2Fwww.healthalliance.org%2Fmedia%2FResources%2Fgeneric-antidepressants-chart.pdf

[Altostrata]

Thanks, Chessie!

[Altostrata]

More information about theoretical antipsychotic equivalencies and switching:

 

Bottaï, T., Dassa, D., & Raymondet, P. (2017). E-medicine: A smartphone application to antipsychotic switch. European Neuropsychopharmacology, 27, S930–S931. https://doi.org/10.1016/S0924-977X(17)31652-8; presentation on Web at https://www.ecnp.eu/presentationpdfs/71/P.3.d.005.pdf

 

Correll, C. U. (2010). From receptor pharmacology to improved outcomes: Individualising the selection, dosing, and switching of antipsychotics. European Psychiatry, 25(S2), S12–S21. https://doi.org/10.1016/S0924-9338(10)71701-6

 

Note cautions given in Correll -- switching is not simply a replacement or change in D2 blockade.

 

att @Go2zero

[Josef]

https://academic.oup.com/view-large/82220812

 

Table for equivalencies of antipsycotics in comparison to 1mg of Olanzapine (amisulpride included)

[Altostrata]

Highly advise one read the entire paper than depend on this table. The paper is full of caveats.

 

Also, it discusses "dose equivalency" in terms of “minimum effective dose methods” which implies the measure of equivalency was a count or assessment of "symptoms" after the change, a method highly subject to researcher bias and other biases. The paper also pointed out a serious limitation of some of  studies it surveyed in that they may have been dependent on dosages packaged by the manufacturer and other data from the pharmaceutical companies.

 

Nowhere is the potential of withdrawal symptoms considered in the discussion of equivalency, which is provided as support to switching of antipsychotics.

 

15 minutes ago, Josef said:

https://academic.oup.com/view-large/82220812

 

Table for equivalencies of antipsycotics in comparison to 1mg of Olanzapine (amisulpride included)

 

[Josef]

I didnt know that it's a part of an article.. my psychiatrist sent me the link, I had to question that before posting,

sorry Alto.

[Josef]

I have this file, I dont know if it's Horowitz's work or not.. 

 

Altostrata- Can you look at it please?

Is the doses and measures are accurate?

Have a good day for now

Appendices for AP paper_Scz Bull.pdf

[ChessieCat]

27 minutes ago, Josef said:

I have this file, I dont know if it's Horowitz's work or not.. 

 

Altostrata- Can you look at it please?

Is the doses and measures are accurate?

Have a good day for now

Appendices for AP paper_Scz Bull.pdf 456.09 kB · 0 downloads

 

I did a search for "Resolution of tardive dyskinesia following cessation of antipsychotics" which I took from the attached document and found the following with the title:

 

The right way and the wrong way to stop
psychiatric medications 2: antipsychotics
and benzodiazepines
Dr Mark Horowitz BA, BSc, MBBS, MSc, PhD (IoPPN, KCL)
Clinical Research Fellow on RADAR trial (UCL, NELFT)
Psychiatry Trainee

 

https://www.rcpsych.ac.uk/docs/default-source/events/congress/2021/speaker-presentations-tuesday/horowi-1.pdf?sfvrsn=bb381fba_2

 

 

Edited October 12, 2021 by ChessieCat

[Josef]

Amazing document! I thank u.

[Josef]

I had a zoom meeting with mark Horowitz a month ago, he supplied me these 2 tables of D2 occupancy (percentages of dopamine blockage) vs dose.

I'm attaching the message we wrote and the excel sheet he sent me

 

Here's Horowitz's message:

Left hand columns show the D2 occupancy of a given dose.
Right hand columns show the dose of a given D2 occupancy
The equations are in there so you could enter in any dose in the left hand columns to work out its D2 occupancy. 
Or any D2 occupancy to find the relevant dose. 

E.g. if you wanted to find out what are 10 equally spaced steps from 50mg to 0 you would take 22.7% D2 occupancy and go to the right hand columns and put in 22.7 going down by 2.27 every step - this would give you 10 equally spaced steps down from 50mg in terms of the effect of the drug on the brain. 

Or you could do 20 equally spaced steps down from 50mg.
I attach a worked example."

D2 occupancy of amisulpride (1).xlsx

[Ruthie3]

Is there any dose equivalent for venalfaxine xl to citralopram? Any information on how to bridge or a direct switch? I know David Healy did direct switches with prozac from venalfaxine but as I had an incompetent psych doing a bridge instead and messed it up badly. I am afraid to try prozac again. If I had been given direct switch it may have helped but now I’m in daily withdrawals from venalfaxine still as no matter what I do I am in wd since I started this med 

 

thanks so much I feel I can’t go on anymore like this, even split dose I am still the same. 

[Ruthie3]

Since prozac

Tapered slowly beads venalfaxine to 92mg from 112.5mg, stopped at 92mg

waking at 2am insomnia hypnic jerks 

split dose then March. 
54.5mg am 

37.5 pm

sleep a bit but wake in withdrawals still. 
body numb still 

lost taste

smell heightened 

 

cannot go on in withdrawals daily like this 

I don’t feel semi human for hours 

need other options