RLS differential diagnosis

[howbeit-abroad]

After a very anxious episode that started earlier this year (around June), I noted an “anxious feeling in my legs” in my journal. This seemed to be very closely linked to my anxiety; as my anxiety improved the anxious feeling would go away.

It sounds a lot like RLS, but I’m finding that I often wake up with it (and will sometimes have leg twitches if I’m trying to sleep in), it gets worse during the day, and by 4-5pm it’s basically fine. It doesn’t affect me at night. This seems like the reverse of the normal RLS pattern.

I’m taking 100mg sertraline in the mornings, which might be relevant. I switched to it from fluoxetine; I was taking the fluoxetine (and had been for many months) when the leg sensations started. I’ve taken SSRIs for many years and this is the first time this has happened.

Any advice? Is this RLS or something else? Thanks so much in advance; this thing is awful and I’m at a bit of a loss. Have been doing the iron thing, but if it’s not RLS presumably iron won’t help…

[Joolsg]

Have a look at the diagnostic criteria for RLS. You certainly meet some of them. Leg twitches while trying to sleep in does indeed sound like RLS. The fact it started when you had been on fluoxetine a few months and now with Sertraline is quite relevant because SSRI and SNRI and tricyclical anti depressants can trigger RLS. However you seem to have been on them for years so something else may be at play. The episode that caused anxiety in June may have triggered RLS.

Does it affect you in the evenings when you're watching tv?

I suggest you get full panel fasting bloods and ensure serum ferritin is above 100, serum iron above 60. Taking ferrous bisglycinate every other night may help.

If your symptoms continue and cause daily distress do not let the GP prescribe dopamine agonists. These are no longer first line treatment among experts and the UK guidance is outdated.

[howbeit-abroad in reply to Joolsg]

thanks so much, will get a blood panel taken. My GP did one a couple of weeks ago but didn’t tell me to stop taking iron supplements beforehand, and didn’t test my ferritin levels… here are the numbers I got back:

Serum iron level (X76tH): 29 umol/L [12.0 - 31.0]

Serum transferrin level (XE2dx): 2.4 g/L [1.7 - 3.4]

Transferrin saturation index (XaERN): 48 % [16.0 - 55.0]

EDIT: ferritin was on the next page, silly me.

Serum ferritin level (XE24r): 57 ug/L [20.0 - 300.0]

Back in June it was much lower, looks like the iron bisglycinate is working slowly.

[Joolsg in reply to howbeit-abroad]

Definitely keep supplementing. Raising serum iron above 60 and serum ferritin above 100 helps the majority of RLS patients and hopefully, in your case, will outweigh the triggering effects of sertraline. Your level of 57 is regarded as normal for most patients but seriously low for RLS. Some need serum ferritin above 200 or 300 before they resolve the RLS.



[howbeit-abroad in reply to Joolsg]

thank you so, so much for your help Jools!! 🙏

[SueJohnson]

Since your Transferrin Saturation Index is 48%, I would discuss taking iron to increase your ferritin with your doctor as it is above 45%. You say it doesn't affect you at night, but you also say you wake up with it and have leg twitches, so it does sound like RLS or at least PLMD which is treated the same way. Since the half life of sertraline is 26 hours, taking it in the morning could still affect you at night. I would try stopping it for a few days and see if that helps. If it does a safe antidepressant for RLS is Wellbutrin or Trazodone. Trazodone also helps with anxiety. Buspar (Buspirone) is also safe for anxiety. Some OTC supplements that help anxiety are Ashwagandha, L-theanine and Honokiol. When you see your doctor Above all don't let your doctor prescribe a dopamine agonist like ropinirole (requip) or pramipexole (mirapex). They used to be the first line treatment for RLS, but no longer are because of the danger of augmentation. Instead ask your doctor to prescribe gabapentin or pregabalin. Beginning dose is usually 300 mg gabapentin (75 mg pregabalin). It will take 3 weeks before it is fully effective. After that increase it by 100 mg (25 mg pregabalin) every couple of days until you find the dose that works for you. Take it 1 to 2 hours before bedtime. If you need more than 600 mg take the extra 4 hours before bedtime as it is not as well absorbed above 600 mg. If you need more than 1200 mg, take the extra 6 hours before bedtime. (You don't need to split the doses with pregabalin) Most of the side effects of gabapentin and pregabalin will disappear after a few weeks and the few that don't will usually lessen. Those that remain are usually worth it for the elimination of the RLS symptoms. According to the Mayo Clinic Updated Algorithm on RLS: "Most RLS patients require 1200 to 1800 mg of gabapentin (200 to 300 mg pregabalin) daily." If you take magnesium don't take it within 3 hours of taking gabapentin as it will interfere with the absorption of the gabapentin. Check out the Mayo Clinic Updated Algorithm on RLS which will tell you everything you want to know including about its treatment and refer your doctor to it if needed as many doctors do not know much about RLS or are not uptodate on it atHttps://mayoclinicproceedings.org/a...

[howbeit-abroad in reply to SueJohnson]

thanks so much!

What’s the significance of the the transferrin saturation index? I don’t fully understand the distinction I think.

[SueJohnson in reply to howbeit-abroad]

It measures the amount of iron bound to transferrin, which increases as the body's iron stores increase. The reason for discussing it with your doctor as it can be an indicator of hemochromatosis although that is not likely in your case.

[cat-a-tonic2]

I'm no doctor. I can write only from my personal experience. I have ME/fibromyalgia, which is a neurological condition whatever some in the medical community still say.

As part of my condition I have suffered from RLS and other uncontrollable muscle spasms, mostly at night. My jaw would also shoot forward, catching my top teeth on my bottom teeth. All of my front teeth are cracked and/or chipped. I would even wake in the night with chips of tooth on my tongue.

I was prescribed fluoxetine after my local NHS at the time decided that I was suffering from a psychosomatic illness, and that I could be cured by being treated as if I was suffering from clinical depression. I was not, at that time. I had suffered depression in the past, and know the difference.

After a few years, when I felt that I was no longer benefiting from fluoxetine, I tried to stop it. It was then that I discovered that it has nasty withdrawal symptoms. I had to wean myself off it very slowly, over eighteen months.

Since then, following advice from a fellow sufferer of ME/fibro, I have been taking a high dose of magnesium for several years. I have found that this has had a miraculous effect on the RLS and muscle spasms. While sometimes I still get discomfort in my legs, it feels more like RLS is trying to happen, but not quite succeeding.

I know that there are many causes for RLS, but it does seem to be a neurological condition. The magnesium treatment is worth a try - and there are no side effects!

[howbeit-abroad in reply to cat-a-tonic2]

thanks! What dose of magnesium do you take? Do you take the citrate salt or a different one?

[cat-a-tonic2 in reply to howbeit-abroad]

I take a high dose - 1,275 mg. It sounds a lot, but that's the dose I have arrived at over years of experimentation. I find that any of the magnesium supplements seem to do the trick. I buy mine on Amazon.