Posted by Noa on March 13, 2001, at 17:09:40
In reply to Re: Any info on 5HT4 receptors?, posted by SLS on March 13, 2001, at 16:53:12
Scott, thank you for looking up the info and explaining it to me.
So you think it is the serzone, while I think it is the venlafaxine, although I am almost afraid to say that here, because it has been getting such a bad rap here these days,and despite the unwanted effects like this one, I think it is a pretty good medication.
Here is a letter I emailed to the author of one of the articles I found on the subject:
Dear Dr. Zorn,
I read with interest your July, 1999, report in Journal of Urology on your findings of a correlation between depression and urge incontinence.
I am treated for depression and hypothyroid with a cocktail of medications that includes the antidepressants venlafaxine (xr) and nefazodone. My experience is that my urge incontinence began *after* initiation of treatment with venlafaxine, particularly after attaining a dose level above 225 mg.
Your article indicates that there was a higher incidence of urge incontinence among patients with a history of treatment for depression, and who scored higher on the Beck, but I did not see any reference to controlling for whether these patients with depression were taking any antidepressants, and wonder if this is something you might have considered, either at the time of your research or since then.
Although there might be a relationship between deficiency in serotonin function and urge incontinence, it has been my "hunch", as a layperson struggling with this problem, that serotonergic antidepressants overstimulate the serotonin receptors in the bladder or ureter (or both). In fact, I have also found support for this idea from the literature.
I recently came across an article by Votolato, et. al. (Serotonergic antidepressants and urinary incontinence.Int Urogynecol J Pelvic Floor Dysfunct 2000 Dec;11(6):386-8), which suggests that activation of the 5HT4 receptors on the bladder might be the mechanism connecting serotonergic antidepressants and urge incontinence.
The role of 5HT receptors in ureter contractions is also discussed by Gidener, et.al. in Urol Int (1995;55(4):202-4), "Influence of serotonin on the human ureter: an in vitro pharmacological study."
Another study suggesting that serotonin could activate the urinary tract is "Effects of drugs on the upper urinary tract of the human" (Urologe A 1986 Sep;25(5):252-8, Hertle and Nawrath). They found that both norepinephrine and serotonin had excitatory effects on the muscle tissue of the ureter.
Similarly, Long and Nergardh, in their study, "Autonomic receptor functions of the human ureter: an in vitro study"(AScand J Urol Nephrol 1978;12(1):23-6), found that "a dose-dependent, reproducible, contraction response to 5-hydroxytryptamine (Serotonin, 5-HT) was demonstrated....This suggests that contraction of ureteral smooth muscle is mediated through receptors which are sensitive to 5-hydroxytryptamine."
My experience has been that the problems I have had with urge incontinence during my waking hours are not present at night. Although I might wake up once during the night to void, it is very rare that the urge feels so compelling that I feel at risk of losing control before reaching the bathroom, whereas this is a common occurrence for me during the daytime. My suspicion is that this is because of the 5HT antagonist effects of the nefazodone, which I take in one dose (350 mg) about 1-3 hours before bedtime. Nefazodone was added to my medication cocktail because of the 5HT2 antagonist effects, to counter the overactivation I have experienced from the venlafaxine (insomnia, restlessness, fidgitiness, restless legs, myoclonus, etc.). I suspect that nefazodone also has some role in reducing my urge incontinence at night, perhaps by inhibiting the excitatory effects of the venlafaxine on the ureter and/or bladder.
I am most interested to hear your response to my comments and to find out if you have considered the issue of serotonergic medications in your finding of a higher incidence of urge incontinence in people with depression, and whether you are undertaking any further research on this topic.
Thank you.
Scott--I actually found Dr. Zorn's whole article at the public library health section, but the citations of the other research are based on reading abstracts. I wish I had access to more journals, and can't afford to order them through the internet. I guess if I really wanted to I would go to a medical library, but just haven't had the time.
I have been sending my pdoc the references and copies of any emails I send to article authors. I will let you know if any of the researchers respond. What do you the the odds are?
poster:Noa
thread:56227
URL: http://www.dr-bob.org/babble/20010310/msgs/56418.html