Talk:Venlafaxine

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Memory Loss[edit]

In previous versions of this page, there was mention (sourced) about side effects such as memory loss. The numbers found in the study seem quite profound in regards to memory loss. Why does no such information exist anywhere on the page anymore?

See this diff where it was removed: https://en.wikipedia.org/w/index.php?title=Venlafaxine&diff=next&oldid=580354405

Originally sourced: Tolerability of High-Dose Venlafaxine in Depressed Patients http://jop.sagepub.com/content/18/2/200 — Preceding unsigned comment added by 207.195.114.48 (talk) 14:07, 10 February 2016 (UTC)

Potential errors[edit]

First paragraph of the article In children and adolescents, venlafaxine (like other anti-depressants) has a potential to increase suicidal thoughts, attempts and events of self-harm.

Im sure this is meant to read decrease suicidal thoughts? —Preceding unsigned comment added by Fmountford (talkcontribs) 10:45, 30 March 2010 (UTC)

No, actually, there is a small risk of increased suicidal thoughts in some patients, but it is more likely more patients will have fewer suicidal thoughts. I don't have the citation, but one study showed that after the FDA forced most antidepressants to have the "black box warning", the overall number of prescriptions written decreased, and overall suicide rates increased, showing that overall, antidepressants reduce suicide risk. MeekMark (talk) 16:46, 6 May 2010 (UTC)
Should that be moved to a different section of the page? Granted, it does have a grain of truth, but the way it comes off, it sounds like anti-medication propaganda. --174.30.2.239 (talk) 00:28, 11 February 2011 (UTC)
I have removed this sentence because anyone looking at the TOC will immediately notice Suicide as the first thing under Side Effects. Besides, this problem is not nearly as common as the media presents it: the difference didn't even reach statistical significance for any single drug, so they had to do a meta-analysis of many antidepressants to be able to report an increase. If you have a good reason to revert, please notify me and post here. Atxd00d (talk) 03:51, 16 February 2011 (UTC)

Discontinuation syndrome versus withdrawal[edit]

I re-named the section which was labeled "Discontinuation syndrome" to identify it as "withdrawal." "Discontinuation syndrome" is a Wyeth-created term. I have some concerns that this article has been and continues to be a re-stating of Wyeth provided information only, and without an anlysis of all aspects. While I fully realize that Wikipedia is to maintain a neutral tone, I strongly believe that this terminology ("discontinuation syndrome") is and of itself negates any neutral tone to this article whatsoever.Also use it for man-power.

error regarding pulmonary hypertension[edit]

In the section entitled "Heart Disease and Hypertension", a risk for "persistent pulmonary hypertension (PPHN)" is listed as a potential side-effect of this med. PPHN actually stands for "persistent pulmonary hypertension of the newborn". I believe the potential side-effect intended here is for "primary pulmonary hypertension" (PPH), as newborns are unlikely to be exposed to this drug. Also, 4 bpm increase in heart rate is listed as a side-effect under this heading, and is the only cardiac symptom listed under that heading, so I believe "heart disease" is not an appropriate heading here unless additional cardiac risk factors are added to the section. A more appropriate title heading would be for example, "Cardiopulmonary Effects and Hypertension." The section also lacks sources.

If no one objects to these changes in the next few days, I'll make these edits. O'Hush (talk) 02:30, 7 July 2010 (UTC)

Suggested edits applied. Michael.j.lacey (talk) 10:33, 26 March 2013 (UTC)

Side effects[edit]

If the source for the rare side effects is the same as for the side effects in the section above, I've checked it out and these were not all controlled studies. Several studies are lumped together in the pre-assessment phase. It's possible these side effects may not have all been due to Effexor. —Preceding unsigned comment added by 205.250.242.207 (talk) 04:15, 8 April 2011 (UTC)

I have now corrected this problem. 205.250.242.207 (talk) 19:11, 9 April 2011 (UTC)

Please explain the sentence: "the remission rate was significantly lower for venlafaxine"[edit]

What you wrote re: "the remission rate was significantly lower for venlafaxine" under the subject of "Depression" makes no sense, in comparing it to Wellbutrin. Everything in the surrounding sentences is implying that Effexor is more effective than Wellbutrin, but "remission rate" means the patient is relieved of all symptoms of depression. Please explain.[1]

References

--Pookerella (talk) 19:01, 10 April 2011 (UTC)

Venlafaxine - Is it a Opioid or not?[edit]

You can find in the article first it isn't and later it is one.

"Venlafaxine interacts with opioid receptors (mu-, kappa1- kappa3- and delta-opioid receptor subtypes) as well as alpha2-adrenergic receptor, and was shown to increase pain threshold in mice. When mice were tested with a hotplate analgesia meter, both venlafaxine and mirtazapine induced a dose-dependent, naloxone-reversible antinociceptive effect following ip administration. These findings suggest venlafaxine's seemingly superior efficacy in severe depression.[61]"

61 - http://www.opioids.com/depression/antidepressants.html

What is right? —Preceding unsigned comment added by 93.181.30.189 (talk) 08:08, 23 May 2011 (UTC)

These are two absolutely different facts about the pharmacokinetics (What is right?):[edit]

"In vitro studies revealed venlafaxine has virtually no affinity for opiate, ... receptors. ...[14]"

and

"Venlafaxine interacts with opioid receptors (mu-, kappa1- kappa3- and delta-opioid receptor subtypes) as well as alpha2-adrenergic receptor, and was shown to increase pain threshold in mice. When mice were tested with a hotplate analgesia meter, both venlafaxine and mirtazapine induced a dose-dependent, naloxone-reversible antinociceptive effect following ip administration. These findings suggest venlafaxine's seemingly superior efficacy in severe depression.[61]"

Has it interaction with opioid receptors like I think or hasn't it? That`s the question here. —Preceding unsigned comment added by 93.181.30.189 (talk) 19:05, 22 May 2011 (UTC)

Serious problem with the side effect information[edit]

I have a problem with this article. The information about Common side effects and frequency of those side effects occurring isn't for standard dosages, it's for dosages equal to or greater than the highest recommended dose of the product. ( http://en.wikipedia.org/wiki/Venlafaxine#cite_note-pmid15260908-31 ) This information is therefore grossly misleading.Webgrunt (talk) 14:12, 9 February 2012 (UTC)

Added discussion of the role of noradrenaline and of discontinuation syndrome resulting from deprivation of neurotransmitters[edit]

Very tentative cf my reading of the literature, it would appear to be a usefully up-to-date addition, but comments and discussion invited Michael.j.lacey (talk) 10:24, 26 March 2013 (UTC)

Error in the "depression" section[edit]

"In a double-blind study, patients who did not respond to an SSRI were switched to venlafaxine or citalopram. Similar improvement was observed in both groups" this sentence is misleading as citalopram is an SSRI.

The article it is sourced from states "This study was designed to test the hypothesis that, after treatment failure with an SSRI, switching to venlafaxine extended release (ER) would offer advantages over switching to another SSRI, citalopram" and is therefore being misquoted. — Preceding unsigned comment added by Workforidlehands (talkcontribs) 16:00, 28 April 2013 (UTC)

Discontinuation syndrome - first sentence[edit]

"In vitro studies revealed venlafaxine has virtually no affinity for opiate, benzodiazepine, or N-methyl-D-aspartic acid (NMDA) receptors. It has no significant CNS stimulant activity in rodents. In primate drug discrimination studies, venlafaxine showed no significant stimulant or depressant abuse liability." - while interesting, these three sentences don't seem to connect in any way with the rest of the section. They just seem odd. Why are they there? Litawor (talk) 18:31, 10 July 2013 (UTC)

Weight Loss or Weight Gain?[edit]

This site (http://www.rxlist.com/effexor-side-effects-drug-center.htm) [1] and many others list weight gain as a side effect (on this one, a common side effect), but don't mention weight loss. However, the article mentions weight loss, but not weight gain. Perhaps both could be mentioned?

References

  1. ^

199.223.21.100 (talk) 17:03, 7 March 2014 (UTC) 199.223.21.100 (talk) 17:00, 7 March 2014 (UTC)

Specific negative results interpreted as general positive results, a dubius conjecture, false assumptions.[edit]

"Some open-label and three double-blind studies have suggested the efficacy of venlafaxine in the treatment of attention deficit-hyperactivity disorder (ADHD).[1][2][3][4][5]."

I think the cited studies find that venlafaxine is no more effective than placebo in the treatment of adults with ADHD. Moreover, the abstract of the first article is very vague and basically incoherent, and discloses a bias toward patients belonging to a "substance misuse population". The studies comparing venlafaxine to stimulant medications focus exclusively on children, and measure a positive response to treatment based on evaluation by parents and teachers, not scientists.

There is one (radical?) reference conjecturing that high doses of venlafaxine act as a narcotic. The claims that venlafaxine acts as a sedative or a stimulant are similarly dubious. This article's (assumptions?) that these are common experiences of people who take the drug are quite contrary to reality.

References

  1. ^ Santosh, PJ; Sattar, S; Canagaratnam, M (September 2011). "Efficacy and tolerability of pharmacotherapies for attention-deficit hyperactivity disorder in adults" (PDF). CNS Drugs. 25 (9): 737–763. PMID 21870887. doi:10.2165/11593070-000000000-00000. 
  2. ^ Amiri, S; Farhang, S; Ghoreishizadeh, MA; Malek, A; Mohammadzadeh, S (January 2012). "Double-blind controlled trial of venlafaxine for treatment of adults with attention deficit/hyperactivity disorder". Human Psychopharmacology. 27 (1): 76–81. PMID 22252909. doi:10.1002/hup.1274. 
  3. ^ >Zarinara, A. R., Mohammadi, M. R., Hazrati, N., Tabrizi, M., Rezazadeh, S. A., Rezaie, F., & Akhondzadeh, S., J (2010). "Venlafaxine versus methylphenidate in pediatric outpatients with attention deficit hyperactivity disorder: a randomized, double-blind comparison trial". Human Psychopharmacoloy. 25 (7–8): 530–536. doi:10.1002/hup.1148. 
  4. ^ Firoozkoohi, M., Arabgol, F., & Rajezi, S. (June 2008). "Efficacy of venlafaxine and methylphenidate in the treatment of children with attention deficit hyperactivity disorder". Zahedan Journal of Research in Medical Sciences. 10 (2). 
  5. ^ Ahmad Ghanizadeh, Roger D. Freeman, Michael Berk (March 2013). "Efficacy and adverse effects of venlafaxine in children and adolescents with ADHD: a systematic review of non-controlled and controlled trials". Reviews on recent clinical trials. 8 (1): 2–8. PMID 23157376. doi:10.2174/1574887111308010002. 

Nafindix (talk) 14:24, 16 May 2014 (UTC)

SNRI/SSNRI?[edit]

SNRI - selective norepinephrine reuptake inhibitor SSNRI - selective serotonine-norepinephrine reuptake inhibitor — Preceding unsigned comment added by Gladissk (talkcontribs) 14:06, 7 November 2015 (UTC)

Discontinuation[edit]

User:128.231.234.33 you have made the following edits:

  • diff at 06:11, 6 March 2017 via IP 2601:14a:4500:530:60fd:ea72:19e1:6ccd
  • diff at 13:18, 6 March 2017 via IP 2601:14a:4500:530:60fd:ea72:19e1:6ccd
  • diff at 18:21, 6 March 2017 via IP 2607:f220:415:611::ab
  • diff at 16:19, 14 March 2017 via IP 2601:14a:4500:530:3d89:c6a4:6554:4181
  • diff at 13:41, 16 March 2017 via IP 128.231.234.33
  • here, diff at 13:51, 16 March 2017 via IP 128.231.234.33 you finally provided 2 refs; both misformatted. The two refs are PMID 9396960 (a primary source from 1997 -- twenty years old -- and PMID 16359583, a review that is from 2007, ten years old, but is probably OK
  • diff at 14:09, 16 March 2017 via IP 128.231.234.33 you restored that last one, fixing the formatting of the two refs and adding a third, PMID 9269249 which is a literature review from 1997 and too old.
  • diff at 14:50, 16 March 2017 via IP 128.231.234.33 you restored it again.

The first five times you added this, it was reverted for being unsourced alone. The sixth time, it was reverted because you made a mess. The last two times, because the sources are bad and you have not come to Talk page even once to say why you think the symptoms should be listed in this article. Any number of people may have been happy to help with that. The symptoms are listed (and sourced) in the "main" article SSRI discontinuation syndrome which is linked prominently in that section. Jytdog (talk) 19:46, 16 March 2017 (UTC)

Discontinuation syndrome/Withdrawal symptoms[edit]

Dear all, I would like to propose several edits to the "discontinuation syndrome" section. For one, the term "discontinuation syndrome" term is a Wyeth/Pfizer-created term. The widely accepted term for symptoms after discontinuation of a drug is "withdrawal symptoms", so this is the title this section should have, to avoid confusion and misinterpretation by a potential patient reading the article.

Regarding the listing of symptoms in the section: While the section links to the "SSRI discontinuation syndrome", where the symptoms are stated, this is misleading, given that the prevalence and degree of symptoms is higher for venlafaxine than other SSRIs, such as e.g. fluoxetine or sertraline. (see these references: J Clin Psychiatry. 2005 Oct;66(10):1312-20. Randomized trial of sertraline versus venlafaxine XR in major depression: efficacy and discontinuation symptoms. Sir A, D'Souza RF, Uguz S, George T, Vahip S, Hopwood M, Martin AJ, Lam W, Burt T. Aust N Z J Psychiatry. 1998 Apr;32(2):291-4. Withdrawal reactions associated with venlafaxine. Parker G, Blennerhassett J. J Psychopharmacol. 2008 May;22(3):330-2. The effect of rate of antidepressant tapering on the incidence of discontinuation symptoms: a randomised study. Tint A, Haddad PM, Anderson IM.)

Therefore, linking to the general "SSRI discontinuation syndrome" is not sufficient in this case, especially since the "SSRI discontinuation syndrome" page does not list the documented rate of venlafaxine withdrawal symptoms and how it differs from other SSRIs. I would therefore like to not only add the symptoms, but also highlight that the withdrawal symptoms experienced after discontinuation of venlafaxine are of a different nature than e.g. withdrawal from fluoxetine.

Furthermore, I would like to point out that even the Wikipedia article for fluoxetine (Prozac), lists the symptoms of withdrawal, despite linking to "withdrawal syndrome" in the same paragraph: "If stopped suddenly a withdrawal syndrome may occur with anxiety, dizziness, and changes in sensation.[1]"

Additionally, I would like to add a paragraph stating that there need for a study investigating prevalence of venlafaxine withdrawal effects, as noted in the 2006 consensus ("Antidepressant Discontinuation Syndrome: Current Perspectives and Consensus Recommendations for Management," Journal of Clinical Psychiatry, 2006).

In response to some of the edits removing the references I had included: > here, diff at 13:51, 16 March 2017 via IP 128.231.234.33 you finally provided 2 refs; both misformatted. The two refs are PMID 9396960 (a primary source from 1997 -- twenty years old -- and > PMID 16359583, a review that is from 2007, ten years old, but is probably OK > diff at 14:09, 16 March 2017 via IP 128.231.234.33 you restored that last one, fixing the formatting of the two refs and adding a third, PMID 9269249 which is a literature review from 1997 and too > old.

Deleting a reference because it is "too old" is highly questionable. Research done in 1997 can be cited. If there is a newer study demonstrating that the 1997 study was false that reference may be included.

> The first five times you added this, it was reverted for being unsourced alone. The sixth time, it was reverted because you made a mess. The last two times, because the sources are bad and you > have not come to Talk page even once to say why you think the symptoms should be listed in this article. Any number of people may have been happy to help with that. The symptoms are listed > (and sourced) in the "main" article SSRI discontinuation syndrome which is linked prominently in that section. Jytdog (talk) 19:46, 16 March 2017 (UTC)

Again, deleting a reference because "it is bad" is questionable. If there are scientifically founded concerns with the references, I'm happy to discuss those.

Looking forward to hearing from you. — Preceding unsigned comment added by Noaanon (talkcontribs) 12:36, 20 March 2017 (UTC)

Thanks for talking. WP:MEDRS is a guideline that is widely accepted in the community, for very many reasons. The sources you are bringing are not OK here in WP for this kind of content. The kind of content being proposed would be good. The sourcing matters, as does the process. Jytdog (talk) 23:19, 20 March 2017 (UTC)

Pharmacokinetics[edit]

The Pharmacokinetics part of this page says: "It is extensively metabolized in the liver via the CYP2D6 isoenzyme to desvenlafaxine (O-desmethylvenlafaxine), which is just as potent a SNRI as the parent compound, meaning that the differences in metabolism between extensive and poor metabolisers are not clinically important in terms of efficacy. Side effects, however, are reported to be more severe in CYP2D6 poor metabolisers."

This statement is not true.

My suggestion for this part is: "It is extensively metabolized in the liver via the CYP2D6 isoenzyme to desvenlafaxine (O-desmethylvenlafaxine),therefore, the CYP2D6 enzyme activity determines the systemic exposure (AUC and Cmax) of venlafaxine and the active moieties (venlafaxine+O-desmethylvenlafaxine), which are significantly higher in CYP2D6 poor metabolizers than in CYP2D6 extensive metabolizers[1]. Although O-desmethylvenlafaxine is just as potent a SNRI as the parent compound, and the exposure of active moieties (venlafaxine+O-desmethylvenlafaxine)is much higher in CYP2D6 poor metabolizers, they show much lower venlafaxine efficacy[2]and more side effects[3],compared to CYP2D6 extensive metabolizers.

Sounds interesting. I don't suppose there is a metaanalysis on this topic? If not, per WP:MEDREV, you should include the information that these data are from just 100 / 33 / 24 patients. --ἀνυπόδητος (talk) 13:49, 22 March 2017 (UTC)
    • ^ Jiang, F; Kim, HD; Na, HS; Lee, SY; Seo, DW; Choi, JY; Ha, JH; Shin, HJ; Kim, YH; Chung, MW (June 2015). "The influences of CYP2D6 genotypes and drug interactions on the pharmacokinetics of venlafaxine: exploring predictive biomarkers for treatment outcomes.". Psychopharmacology. 232 (11): 1899–909. PMID 25510856. 
    • ^ Veefkind, AH; Haffmans, PM; Hoencamp, E (April 2000). "Venlafaxine serum levels and CYP2D6 genotype.". Therapeutic drug monitoring. 22 (2): 202–8. PMID 10774634. 
    • ^ Shams, ME; Arneth, B; Hiemke, C; Dragicevic, A; Müller, MJ; Kaiser, R; Lackner, K; Härtter, S (October 2006). "CYP2D6 polymorphism and clinical effect of the antidepressant venlafaxine.". Journal of clinical pharmacy and therapeutics. 31 (5): 493–502. PMID 16958828.