Ongoing fatigue and gastrointestinal issues with no clear diagnosis

[molly5678]

I wonder if anyone can give me some advice
For years I’ve suffered on and off with malaise and fatigue with gastrointestinal issues
I’ve had so many tests but the only result that’s a bit off is my serum ferritin which is in the 20s
I seem to be getting worse and have less and less ‘good’ days…on a good day I can exercise, socialise and function but on a bad day everything is an effort and I’m dragging myself through the day and have to cancel plans
my latest trip to the GP ended with some blood tests for auto immune issue but the GP said that if the results are negative then they don’t really know what is wrong with me apart from the possibility of mild chronic fatigue but he also seemed to think it was unlikely as ‘you aren’t bed bound or housebound and can work’
I’m just at a loss of never knowing how I’ll feel day to day

I had very low iron levels too, I felt like I was walking through treacle and found it hard to force myself to do anything I was so tired all the time. I did get given iron supplements, but I did feel like the GP didn’t take it seriously. I am better now, but not 100%. Mine was never tested, but have they done a thyroid check? Also with frequent gastro issues have they considered something like ulcerative colitis and offered a colonoscopy? A relative was eventually diagnosed with it and treatment makes him feel much better. Have a look at the symptoms of both to see if they match yours.

Is the autoimmune test a test for Coeliac Disease? Because what you are describing sounds exactly like the symptoms of Coeliac Disease

If you can afford it, see a private rheumatologist. The high ferritin is a marker that you have some inflammation in your body, but there are so many different possible causes of high ferritin. That being said, the 20's isn't actually out of the reference range is it? What are the units?

Have you had any ununtentional weight loss? Your GP should really go further to work out why the ferritin is high and the cause of your symptoms, but given the state of the NHS it doesn't surprise me that they won't. A good rheumatologist would look into it properly for you, but probably only priv

*private would actually take the time to get to the bottom of things

Thanks very much for taking the time to reply, I really appreciate it.
I was tested for coeliac a few years back and it was negative.
serum ferritin is low at 26 ug/l when normal range is 15 to 150…NICE guidelines say below 30 is iron deficiency but the GP was having none of it and said that isn’t causing my symptoms.
I tried to explain that my gastrointestinal issues have worsened but I got the classic shrug and ‘you have iBS’

serum ferritin is low at 26 ug/l when normal range is 15 to 150…NICE guidelines say below 30 is iron deficiency but the GP was having none of it and said that isn’t causing my symptoms

This doesn't make sense - did the GP explain why they don't think low ferratin could be the cause when according to NICE you are deficient, given that ferratin difficiency can explain almost all your other symptoms? I'm not disputing it but on the face of it, this seems more logical to be contributing than not?

Gastro issues can mean you don't absorb vitamins as well, leading to deficiency, leading to the other symptoms.... you haven't been on PPI have you (omeprazole or similar)?

I have chronic fatigue syndrome (aka ME). Your GP is incorrect to say you can’t have it because you work and are not housebound. Although it is true to say that most people witb ME can’t work. Have a peruse of the ME Association website, especially the ‘free literature’ section.

Eg this leaflet. Look at the 10% disability section:

https://meassociation.org.uk/wp-content/uploads/2025/10/DISABILITY-RATING-SCALE-ON-MECFS-V2.pdf

Incidentally, most GPs are very uninformed about ME and mostly give out incorrect or outdated information. For example, my very lovely and wonderful GP told me the treatment was graded exercise therapy - but that was removed from the NICE guidelines in 2021. (Unfortunately she didn’t appreciate it when I told her that). But it’s Not really their fault - they get virtually no training on it and ME experts don’t know much about it either.

The ME Association has a helpline. It might be worth calling them.

Can I ask what your gastro symptoms are? I'm going through similar at the moment. IBS flare or so GP says and anxiety. Had bloods done and my cholesterol is high and my bone profile is low. I'm also fatigued a lot.

Have you had a colonoscopy?

Have you seen a dietician and done a proper FODMAP exclusion diet process? It's not recommended to try it alone - many lists in the Internet are conflicting and just plain wrong. That will help you identify any food triggers but also they can focus on looking at whether you have difficulties in absorbing iron and get you as healthy as possible on that front.

High dose iron tablets, taken with fresh orange juice, should help too.

Also, you can pay for private iron infusions, which may well be worth a go here as your numbers are low but it is expensive.

I would have thought the Dr would refer you to a gastroenterologist then you be able to have more tests like a colonoscopy if you haven't had one.

Erm..Ferritin of 20ish is low, not high! Blood test ranges tend to say about 18 is ‘normal’, but most people need it to be above 70 to feel well and above 100 to be optimal. I felt dreadful when mine was 13. People kept telling me I looked ill, my hair was falling out, I was pale.
OP have you been referred to gastro?

Thank you so much ladies
I really do think it’s the Serrum ferritin and I’m going to push that with the GP…he was very dismissive and kept calling me ‘my dear’..very patronising

gastro symptoms are excessive wind and stomach pain with bloating

I think that's a good plan. It's mad that he won't even consider treating for low iron to see if it helps, given a) NICE guidance suggests you need it and b) it's not an expensive or invasive treatment.

I'm not an advocate for "trial by error" treatment, but if he can't give you a meaningful reason why it isn't that, I'd be pretty suspicious. For what it's worth, I was in a similar situation, and it only got treated when my ever decreasing ferratin hit such a low level they couldn't ignore it anymore! And that sorted out all my symptoms.

If he won't prescribe or give a good reason not to, I'd be seeking a second opinion.

I've had very similar symptoms OP apart from this week they ramped up a lot and I have constipation which is unusual for me.

Thanks for all the advice
just an update….blood results all normal..serum ferritin up to 36 which is highest it’s been in 10 years!

In my experience medics don’t give a shit about low ferritin unless it’s in the context of other abnormal blood markers, but it absolutely could explain your symptoms - when mine was 9 I felt like death, I couldn’t even breathe properly (air hunger). Start taking iron but you might have to try a few different types before you find one you can tolerate.

I just don’t understand why they are so dismissive of it!
May I ask how you raised your levels @Trumptontown

Have they ever suggested to refer you to a gastroenterologist and having a colonoscopy. Has the Dr done the stool test which shows imflamation in the gut. What tests have you had.

Chronic fatigue is often linked with metabolic syndrome, so take a look at that.

Do you take NSAIDs? NSAID enteropathy is an often missed cause of digestive issues. It can cause malabsorptian and bleeding which leads to low iron and fatigue. Tests for the usual causes often come back clear as it can come and go depending on whether you're actually taking the NSAID at the time.

I got prescribed Ferric Maltol in the end, but basically you need to find an iron supplement that works for you.

Take iron on an empty stomach if you can tolerate that, and take a vitamin C tablet at the same time (orange juice doesn’t have enough vit C in it). Make sure you’re not taking any medications that can inhibit iron absorption (PPIs for example) and if you are, take them at opposite ends of the day. If you can’t tolerate it on an empty stomach then take it after food, and if you still can’t tolerate it then switch to every other day. Vitamin C is a cofactor but look up other iron cofactors too and make sure you are getting enough of them in your diet or via supplementation.

If you have heavy periods then address those too.

crohn's disease?

Have you had your b12 levels checked?

I have always had problems keeping my Iron levels up and a couple of months ago was just so unwell I could barely function, extreme fatigue, pins and needles, headaches, stomach issues etc and turns out I cannot absorb b12 so need to have injections.

B12 is such an 'easy fix' yet the test is classed as an 'additional investigation' so unless your doctor specifically requests it, it is not tested as standard.