I suffer from PLM and had low ferritin. I've taken oral iron for some years to keep my ferritin above 100. I've read that one of the adverse effects of iron sulfate can be stomach/intestinal upset. I'm experiencing my 4th episode of intestinal upset in a month. At first I thought it might be food poisoning. Symptoms would start about 4 am (a few hours after dinner and taking 65 mg iron sulfate) and continue for a few hours-2 days. But 4 times in a month? Diarrhea was very watery similar to a colonoscopy prep. I don't think I had a fever but only measured it once (97.2 F). I got very tired and would sleep most of the day. My wife and I eat much of the same stuff and she has been fine.
Could my problem be due to iron sulfate? Is so, why now after taking it for years? If its the iron sulfate why are there days where I feel fine?
Also, I'm wondering if anyone else has have a similar adverse effect from iron sulfate? How bad and what were your symptoms? How long did they last?
Could my issue be a side effect of pregabalin (300 mg)?
Thanks
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my mother can't tolerate ferrous sulfate, too - she expected constipation as a side effect, but has diarrhea instead, she stopped it after 2 months, had a couple months off, but since her RLS is not controlled well enough, went back for a couple of days and diarrhea again. As for being sleepy, pregabalin can definitely do that. Iron i/v injections seem to have no intestinal side effects.
Ferrous sulphate side effects can include feeling or being sick (nausea or vomiting), stomach pain or heartburn, loss of appetite, constipation or conversely diarrhoea, dark or black faeces.
Why you should have been fine for years and only recently started having a problem is more difficult: you should really take this to your doctor, as it could indicate some other bowel problem.
Meanwhile, I'd stop taking the sulphate for a while and try taking ferrous bisglycinate (Gentle Iron) and see whether you still have the same problem: that in itself will tell you (or your doctor) something.
I would follow ChrisColumbus suggestion to see if the iron sulfate is causing the problem. If not, it could be the pregabalin. Do not stop taking the pregabalin cold turkey though. You would need to reduce it very very slowly or you will have withdrawal effects. It you do so slowly you won't have any. You could also try switching to gabapentin if it is not the iron. Although they are basically the same drug except you need to divide the doses, and the side effects are basically the same, some people find that the side effects that bother them on one don't bother them on the other. Multiply the pregabalin amount by 6 to get the correct dose. Since you are taking 300 mg pregabalin, you would need 1800 mg of gabapentin. Take it 1-2 hours before bedtime. Since you need more than 600 mg take 600 mg 4 hours before bedtime as it is not as well absorbed above 600 mg. And since you need more than 1200 mg, take 600 mg 6 hours before bedtime.If you take magnesium don't take it within 3 hours of the gabapentin as it reduces the absorption of the gabapentin.
Have you started any OTC supplements or new medicines or changed your diet or lifestyle recently? And of those could affect your RLS.
Thanks Sue, I am near the end of transitioning from gabapentin (1800 mg) to pregabalin (300 mg). I might try going back to the gabapentin but I will stop the iron sulfate first. I'm also trying to see my GP about my intestinal upset but the medical system is so overloaded I need to be near death to get in quickly. I have not started any new supplements or meds except for the change to pregabalin. As you note, these are basically the same drug so it seems unlikely to be the problem. As for diet, my wife and I have been slowly trying to eat better (less sugar and inflammatory stuff). We have also given up drinking (2 months now). My wife joked that maybe my gut biome is having alcohol withdrawal symptoms. Lifestyle has not changed, I am quite physically active. My other hypothesis is food poisoning but 4 times in a month? And my wife hasn't been sick.
Its been hard to tell if pregabalin has been better than the gabapentin. It seems like there is alot of other unknown stuff going on. My PLM is quite variable so i need to assess changes over a period of weeks. At first the pregabalin seemed more effective as I expected but now I'm not sure. I have been sleeping longer (6 hrs to over 7 hrs) which is a good thing. My brain fog/memory is probably worse but that often happens with illness.
our symptoms sound like mine. I put it down to IBS and my Dr. Agrees. My daughter suffers the same It’s a case of figuring out what you have eaten or drunk. Sometimes it’s what you ate 2 minutes ago and sometimes 36 hours ago so not easy. I was told to follow the FODMAP diet. Not done it yet as it’s very restrictive and I’m already at the bottom of the BMI scale but could be good if you also want to lose weight.
I was on Pregabalin for about 6 mths, went up to 400mg, then and took myself off, slowly by 25mg ever week, the reason being that it created significant brain fog, blurry vision and memory lapeses (couldn't find words, stopped sentences midway unfinished - very unlike me! ). But I wasn't sleepy and my digestion was fine on it. Normally I have IBS and need to be conscious of what I eat so for me the only upside of Pregabalin is that is slowed my otherwise too fast digestion. It did not help RLS at all which was hugely dissappointing! I have still not decided which way to go from here - opioids is the only option left, or trying to stay 'natural' - not great either way. All the best for a suitable solution for your RL!
Replying to myself to provide some followup. I've concluded I must have had food poisoning or some related illness. I stopped the iron for a few days and restarted it with no issues. I continue to take pregabalin and feel fine. Thanks to all who took the time to respond.
According to my sleep doc, my illness could have made my PLM worse because the medications might not have been absorbed as well as normal.
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