Serotonin Systems, Gut Systems and Gravity

Young folk are probably less likely to read a post about bowel problems on meds because their bowels generally work without a hitch. They haven’t had to learn to accommodate to the loss of elasticity that comes with age, which can make Gravity Feed an instantly recognizable concept for older people, especially when on meds.

Six years ago, RxISK ran a Bladder and Bowel Problems on Antidepressants post that attracted a lot of comment especially on bowel problems. Perhaps because the case outlined was so shocking – a young woman who ended up committing suicide because of Pelvic Floor Dyssynergia triggered by her antidepressant. The medical input at the inquest surprisingly said this was not uncommon – a surprise to anyone like me who had never heard of it.

The comments linked to the post were much more focussed on the actual bowel problems at the heart of the post than on the machinations of pharma companies as can happen with other posts.  There clearly was a need for more posts in this area but it kept getting put off.

The number of comments should have come as no surprise.  Most of our serotonin is in the nerve fibers and blood vessels that make our bowel wall, and mucosa lining it, work. This mucosa is continuous with our skin and is just as much outside our body as our skin is. Combined they, and not our brains, form the boundary between us and our world and are the place where our bodies encounter the world and sense what is going on or going wrong.

Drugs that interfere with serotonin are likely to cause problems and not just the constipation or diarrhea caused by drugs acting on noradrenaline (nor-epinephrine).  It is not just SSRIs that cause problems – drugs like mirtazapine, quetiapine and olanzapine also act on serotonin systems and cause cause serious problems, but may seem less likely to do so because they are less commonly used.  Mirtazapine etc can also cause visual snow and PSSD etc but we hear about it and others less.

Googling SSRIs and gastroparesis reveals a grim story.  And as luck would have it, the BBC ran a scary news story yesterday Woman with Paralyzed Stomach about a young woman who had nearly died because for years her gastroparesis was misdiagnosed as anorexia nervosa.  She was not taken seriously.  .

Three Cases 

K

K is a 26 year old man who has had severe small intestine dysmotility for 18 months. Before this developed, he was an athlete and had no medical issues.

He had an episode of high blood pressure, triggered by a corticosteroid injection for back pain that lasted for a month. This was treated with metoprolol, valsartan and amlodipine, which caused no gastrointestinal problems. After a month, he could stop the blood pressure drugs and started to take 20mg escitalopram daily for stress.

His gut problems developed during 2 months on escitalopram, gradually got worse, and have persisted after stopping. On escitalopram, his abdomen swelled after the morning dose and got bigger during the day. The next morning, he was normal and could defecate before taking the next dose. If he missed a dose he was normal that day with no abdomen bulging.

He consulted his doctor and then many other doctors. They all said It was not real. He began to taper but this was not easy. Tapering rapidly caused feverish symptoms. Tapering over a month, every time with a lower dose of drug, the same “big abdomen story” happened. When he stopped he was left with a paralyzed intestine which could not move anything forward, forcing him to go on a hunger strike for two weeks.

He had various tests under supervision of gastroenterologists – enteroscopy, MRI, blood tests, X Ray etc. All other causes were excluded, leaving him with a disaster which was called severe small intestine dysmotility.

Metoclopramide and domperidone, often used to settle bowels, offered some help. But after 6 months of a difficult life with these, having had a series of intestinal pseudo-obstructions and hunger strikes, he started showing cardiac symptoms to these prokinetic drugs.

He located a Professor Jiande Chen in John Hopkins University, who is listed as an intestinal motility expert. Dr. Chen has been pioneering Electro Acupuncture for small intestine dysmotility.  For a period of time, this helped but K felt his body was losing its sensitivity to this method.  The cardiac problems he had on the steroid began to comeback and he had no option but to stop leaving him worried that he will end up on total parenteral nutrition and death.

K’s research revealed the obvious – that serotonin plays a big part in gut function and that SSRIs can irreversibly damage 5HT neurons, which are important for intestinal motility and if the damage is too great it can be lethal. As 5-HT neurons exist in any part of the body (e.g. sexual system, brain), SSRIs have the potential to target them. He views his current problems as a gastro-intestinal version of PSSD or the many other neurotoxic effects SSRI drugs can have and worries that they are irreversible.

He thinks these drugs are so risky, they should be restricted to severe medical conditions that do not respond to anything else and should not be used for something like the stress he had.  Even then, he thinks, they are best not used in combination with anything else or when the person has recently been treated for other conditions or instabilities – like the back pain and the adverse response to steroids that sent him down this path..

Jan-Carol

JanCarol is one of the moderators on Surviving Antidepressants

When I was a child, we moved into the wheat fields of Kansas, and I erupted into “hay fever” or sinus allergies.  The treatment at the time was desensitisation through allergy shots and heavy antihistamines.

So from the age of 7, I was on heavy antihistamines like Chlortrimeton.  At age 11, I was switched to Benadryl and struggled to stay awake in school on this. I had no idea it might be doing something to my body.

When I got my periods at 13, they were horrible.  In hindsight (now 61), I think that was because I was chronically constipated as a child.

I was an active, intelligent child, did well in school.  I had other stressors, being an adoptee to a mother whose religion was invasive, intrusive and controlling.  We also moved every two years, and so I was always the “new kid”.

When adolescence hit, I did indeed go berserk.  I started dating, trying to relate to others. I realised later that the antihistamines made me crabby, grumpy, difficult to get along with.  They may have been a contributing factor to my later “depressions.”

My “crazy” was acceptable until my first marriage to a traumatised, depressed man, who later committed suicide.  That’s when the antidepressants started.  I suffered frank hallucinations on Prozac, so doctors did the “find the right drug” game, and often they put me on tricyclics.  I can’t remember all of them, now.

From 1988 until 2016 I was drugged on antidepressants of one form or another, while still on antihistamines until about 1996.  I may have had some time off antidepressants, but always ended up back on them.

By the time I found Mad In America, Rxisk and Surviving Antidepressants around 2013, I was on lithium, Seroquel and prothiaden.  Three years of tapering, and I was free of the psych drugs.

I was unaware of bowel trouble until then. I suffered 5 years of diarrhoea, and an attempt to fix a rectal prolapse which failed.  Had the antidepressants contributed to this?  I did find a functional medicine practitioner who took a bowel biome profile and prescribed probiotics to correct it.

It’s been better – but after chronic use of meds I am left with a floppy bowel, and a very delicate balance with digestion.  Like many others I’ve heard from, I am afraid to put food in, because it’s so painful coming out.  From what I can feel, my large intestine is all sagged down into my lower belly and coiled like a snake.  In order to evacuate, it has to push against the other side of the snake.

If you imagine the snake has eaten a large rat, he doesn’t coil up to digest it!

So – now I have IBS-C (combination).  Half the time I’m constipated (I count how many meals are in me), and then all hell breaks loose.  But with the floppy bowel, it amounts to “slow diarrhoea” – only 6 inches of the bowel can evacuate at any time, because it’s all coiled up.  So, a bout of diarrhoea takes all day to evacuate, 6 inches at a time.

I’ve had 5 colonoscopies, but because of the floppy bowel, it takes me a week of fasting to get clear for the test.  The last colonoscopy came up with small diverticula, but nothing wrong.

When I hear doctors and psychiatrists say something like, “you’ll be on this for the rest of your life” I am fearful, because nobody knows the long-term effects!  It took me 10 years off the drugs to realise just how much damage was done.

Katie BT

Katie has featured here before in Girl on a Hot Tin Roof and Doctors and Withdrawal and was the inspiration for this image.  The piece below comes a decade later.

Some issues have improved, although still persist with less intensity. A series of these began in 2013 in the context of the SSRI taper affecting my pelvis, butt, bladder, autonomic nerves, hands, feet, and face.

However, I am having new symptoms, especially since May 2024.  My digestive system stopped working at the end of May. I don’t feel constipated. There is a numbing of sensation. I went 6 weeks without feeling any sensations in my abdomen and then started to feel fullness and upper abdominal pressure and early satiety. I am unable to have a bowel movement without Miralax, which I started taking daily in July. If I lived somewhere where I did not have access to Miralax, I would not be alive.

I have had a major change in sensation in the pelvic floor muscles. I had an episode of fecal incontinence last week – the Miralax worked but I am numb and cannot feel the waste leaving my body. I did not have normal cramping sensations when completing a colonoscopy prep a few days ago; any sensations I did have were muted. I think I have gastroparesis and that this is a progression of the small fiber neuropathy.

I am alternating between feeling over vigilant/alert and then the total opposite – feeling very tired, cognitively out of it, heavy, full. These states can last for days. They often seem temporally related to going longer without eating vs. eating.

These changes occurred spontaneously without a change in any medication except for getting off of birth control in May 2024. Some new symptoms were gradual in their onset over several recent years but there has been an intense surge of multiple new symptoms starting in May that continues to unfold.

I’m still on an SSRI (31 years of exposure). I’m also on several additional agents (regrettably added in the early years to manage the akathisia) that may also be toxic

Staying on Coming Off

Katie is someone who opted to stay on meds despite all the problems this has caused her  This issue will be picked up in another post before a Mad in America Webinar on Antidepressant Dysregulation and how to come off these medicines and perhaps repair the damage they have caused.

See Why Are Antidepressants so Difficult to Stop