<p>Venlafaxine at low dosages strongly inhibits serotonin, at moderate dosages also norepinephrine and only high dosages it also inhibits dopamine.</p>

<p>The ratio is the following.</p>

<ul>
<li>serotonin : norepinephrine : dopamine</li>
<li>1 : 30 : 93</li>
</ul>

<p>According to the <a href="https://www.accessdata.fda.gov/drugsatfda_docs/label/2009/020151s054lbl.pdf" rel="nofollow noreferrer">FDA data</a> these are the percentages for side effects.</p>

<ul>
<li>Libido decreased</li>
<li>Placebo 75mg <strong>225mg</strong> 375mg</li>
<li>1.1% 2.2% <strong>1.1%</strong> 5.7%</li>
</ul>

<p>Here are the results for other sexual dysfunctions.</p>

<ul>
<li>Abnormal ejaculation/orgasm</li>
<li>Placebo 75mg <strong>225mg</strong> 375mg</li>
<li>0.0% 4.5% <strong>2.2%</strong> 12.5%</li>
</ul>

<p>and</p>

<ul>
<li>Impotence</li>
<li>Placebo 75mg <strong>225mg</strong> 375mg</li>
<li>0.0% 5.8% <strong>2.1%</strong> 3.6%</li>
</ul>

<p><strong>How would you explain the sudden drop of sexual dysfunctions at 225mg?</strong></p>

<p>Other questions to consider:</p>

<ul>
<li>Would a lower dose (37.5mg or 25mg) have sexual side effects (SSE) similar to placebo?</li>
<li>What dose has the lowest rate of SSE?</li>
<li>What is the lowest effective dose with reasonably low SSE?</li>
<li>How would adding of NDRI (bupropione) influence SSE given an increased dosage of venlafaxine? (i.e. Could one afford higher doses
of venlafaxine with few SSE provided bupropion is taken
concomittantly?)</li>
</ul>

CC BY-SA 4.0
2019-01-05T00:53:25.193Z
Seeing as you asked a similar question a while ago at https://psychology.stackexchange.com/questions/21298/induced-sexual-dysfunctions-antipsychotics-vs-antidepressants are you in any position to write an answer to that question or is this one an offshoot after further research?
Chris Rogers
CC BY-SA 4.0
2019-03-18T00:02:54.280Z
The difference between  2.2% and 1.1% may not be statistically significant.
got trolled too much this week
<sexuality><depression><psychopharmacology><serotonin><neuro-transmitters>
Why does venlafaxine have lower incidence of sexual dysfunctions at higher doses?
Slazer
# Why does venlafaxine have lower incidence of sexual dysfunctions at higher doses?

(Asked by: username_0 on 2019-01-04)

Venlafaxine at low dosages strongly inhibits serotonin, at moderate dosages also norepinephrine and only high dosages it also inhibits dopamine.

The ratio is the following.

* serotonin : norepinephrine : dopamine
* 1 : 30 : 93

According to the [FDA data](https://www.accessdata.fda.gov/drugsatfda_docs/label/2009/020151s054lbl.pdf) these are the percentages for side effects.

* Libido decreased
* Placebo 75mg **225mg** 375mg
* 1.1% 2.2% **1.1%** 5.7%

Here are the results for other sexual dysfunctions.

* Abnormal ejaculation/orgasm
* Placebo 75mg **225mg** 375mg
* 0.0% 4.5% **2.2%** 12.5%

and

* Impotence
* Placebo 75mg **225mg** 375mg
* 0.0% 5.8% **2.1%** 3.6%

**How would you explain the sudden drop of sexual dysfunctions at 225mg?**

Other questions to consider:

* Would a lower dose (37.5mg or 25mg) have sexual side effects (SSE) similar to placebo?
* What dose has the lowest rate of SSE?
* What is the lowest effective dose with reasonably low SSE?
* How would adding of NDRI (bupropione) influence SSE given an increased dosage of venlafaxine? (i.e. Could one afford higher doses
  of venlafaxine with few SSE provided bupropion is taken
  concomittantly?)

**Tags:** sexuality, depression, psychopharmacology, serotonin, neuro-transmitters

> **Comments:**
> **username_1**: Seeing as you asked a similar question a while ago at https://psychology.stackexchange.com/questions/21298/induced-sexual-dysfunctions-antipsychotics-vs-antidepressants are you in any position to write an answer to that question or is this one an offshoot after further research?  
> **username_2**: The difference between  2.2% and 1.1% may not be statistically significant.  

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## 0 answers

