Foot jerks when falling asleep--what is this?

Lately my foot repeatedly either drops up or lifts up from the ankle as I'm trying to fall asleep. It seems classic for PLMS, although supposedly my "PLMS" on previous sleep studies were muscle contractions related to respiratory events (this determined while I was on 1200mg of Neurontin, I might add...). I have never been conscious of PLMS, even when I supposedly had them. These are interfering with my falling asleep, as they happen each time I start to doze off.

Also, how likely is it that a newer generation antihistamine/decongestant (i.e., Allegra-D) would cause this?

I have taken allegra D and not had this happen, I dont know..

So this just started, and you never noticed before?

I put up another thread about leg movements too, as I am also curious how to differentiate between rem dreaming leg movements,

the just before you fall asleep jerks to get settled, and PLM...

I was starting to have some more of these episodes prior to starting the Allegra-D, so I don't know if this is just where it was heading, the medication, or if it could be exacerbated by lots of exercise (we were walking a ton for a week).

I have never heard of movements during REM. I thought REM was characterized by muscle paralysis?

Restless Legs tends to refer to an uncomfortable sensation that requires moving your legs to alleviate--it's based on clinical report of symptoms. PLMs are something detected on a sleep study (don't ask me how they are scored, because I don't know). I have had both at various times, but was not aware of the PLMs until recently, and as I said, I was told my PLMS are not true PLMS, but are muscle contractions associated with respiratory effort (I question whether that is something that can be known on 1200mg of Neurontin, though...).

my husband jerks around in rem like a dog.. so I guess not everybody gets completely paralyzed.. he was a really big sleep walker when he was younger
too.. He even went on his paper route when he was sound asleep!

okay, so the PLM are associated with apnea events?

If what was different was you walking a ton, and that must have been fun! .... maybe thats it..


I have RLS but no PLM, just the hot burning feeling on my arms legs and body... in the other thread, I mentioned I thought it was a food allergy
for thirty years, but the doc said it was a more unusual form of RLS...

my cousin has rls without PLM, only she gets the sensation she has to get up and walk around, that its this uncomfortable buzzing or crawling
sensationg in her legs.. mine is totally different, and its in my arms too and the rest of my body..

I dont know what the heck is making your jerks start now...

How is your surgery recovering coming along?

Since there is a very close connection between Restless Leg Syndrome (RLS) and Peroidic Limb Movment Disorder (PLMD) - 80% patients with RLS have PLMD but not vice versa. It wouldn't surprise me if antihistamine isn't causing the problem.

Caffeine, Chocolate etc. also causes limb movements at/during sleep.


2008 Study from John Hopkins

To sort out the relationship they suspected, the researchers first gave 12 RLS patients either a true sedative or diphenhydramine, the active ingredient in many allergy medications that tames histamine and induces sleepiness. They found that while sedatives had little to no effect on RLS, diphenhydramine made the RLS as much as three to four times worse. The team then looked at autopsied brains from RLS patients for possible differences in histamine receptor location and found that the substantia nigra, the part of the brain implicated in RLS, contained a higher number of histamine-3 receptor proteins, suggesting that this molecular pathway is more active in people with RLS.

"Five out of six patients in our study showed this elevated number of histamine receptor proteins," says Richard Allen, Ph.D., a research associate in neurology at Hopkins. "The histamine system appears to alter the balance of the nervous system so that one is not sleepy in the daytime, even with sleep loss, which might explain why RLS patients can get by on so little sleep. This also suggests that histamine receptors might be a new target for study and therapy of RLS."

SleepingUgly wrote:Lately my foot repeatedly either drops up or lifts up from the ankle as I'm trying to fall asleep. It seems classic for PLMS, although supposedly my "PLMS" on previous sleep studies were muscle contractions related to respiratory events (this determined while I was on 1200mg of Neurontin, I might add...). I have never been conscious of PLMS, even when I supposedly had them. These are interfering with my falling asleep, as they happen each time I start to doze off.

If they are associated with difficulty falling asleep, then they might well be RLS, but not PLMs---since PLMs always present exclusively during a state of sleep across the patient population. If, on the other hand, they are associated with being awakened during sleep, because of sleep-disruptive leg movements, then they just might be PLMs.

Clincher: If they are accompanied by an urge to move your legs while trying to fall asleep---quite often described as "a creepy, crawly" urge---then they are almost certainly RLS versus PLMs. Unlike RLS, PLMs are not accompanied by that sudden urge to move the leg. And in that case you probably have both RLS and PLMs. If your leg movements happen during wakefulness while trying to fall asleep, but they are NOT accompanied by an urge to move the leg, then I would suggest visiting a neurologist for diagnosis.

Unfortunately every problem has it's onset or transitional period. So while they might not have presented during your PSG, that's not to say they are not symptomatically manifest today. Also, my understanding is that PLMs and RLS can be variable or episodic. Good luck with that, SU.

SleepingUgly wrote: Also, how likely is it that a newer generation antihistamine/decongestant (i.e., Allegra-D) would cause this?

The decongestant or "D" in Allegra-D is pseudoephedrine.

And here's the Google "chatter" about RLS and pseudoephedrine:
http://www.google.com/#sclient=psy&hl=e ... a61d5b9175

And since the most common OTC pseudoephedrine offering is Sudafed, here's some more just-as-relevant Google chatter about Sudafed and RLS:
http://www.google.com/search?q=%22exace ... a61d5b9175

Bottom line: the "D" in Allegra-D is known to exacerbate RLS symptoms.

This reminded me that when I gave Mike 2 Benadryls one night this summer for a nasty,itchy mosquito bite, he had lots of leg movements pretty much all night. He didn't seem to wake up but he also didn't seem as rested the next day either.

Another variety of sleep-related movements are called "hypnic jerks" --if it''s any consolation, at least the name is comical.

The unique characteristic of H. J.''s is their occurrence during the twilight between wakefulness and sleep.

I don't think they are understood, but then, you could say that about much of sleep physiology.

http://en.wikipedia.org/wiki/Hypnic_jerk

H.J movements are not limited to legs. My wife often has them in her fingers for a minute or two as she's falling asleep. It's as though she's playing a piano. They don't awaken her, and they're so uniquely her that I have come to find them endearing.

-SWS wrote:If they are associated with difficulty falling asleep, then they might well be RLS, but not PLMs---since PLMs always present exclusively during a state of sleep across the patient population.

Apparently there are PLMWs (?!), which occur during wakefulness and can occur while falling asleep. I described it as PLMS because of the classic dorsiflexion of the foot at the ankle. My perception was that I was starting to dose and each jerk would startle me more awake, and then the process would start over.

I don't know if this link will work, but this is about PLMWs:

http://books.google.com/books?id=hFNifH ... on&f=false

I have had both RLS sensations and this dorsiflexion of the foot at various times lately. In the past, I occasionally had RLS (it's growing more frequent), but was not aware of the dorsiflexion of my foot.

-SWS wrote:If your leg movements happen during wakefulness while trying to fall asleep, but they are NOT accompanied by an urge to move the leg, then I would suggest visiting a neurologist for diagnosis.

You want me to go to a doctor?! I hate doctors. What will a doctor do for me besides put me on more medications, which will cause me a host of other problems?! OK, I'm going to my sleep doctor this week, and I'm sure we will have a very helpful dialogue along the lines of this:

Doctor: What medications are you taking?
Me: I just gave the list to your nurse and she entered them in the computer.
Doctor: I still have to go over them with you.
Me: Why? Don't you think your nurse is competent?
Doctor: These are the rules.
Me: You're going to have to do more for me than just review my list of medications with me each time you see me if you want to save my life, Doctor.
Doctor: Are you dying?
Me: Doesn't it say "DNR" on my chart?
Doctor: No, why would it--
Me: Then, Doctor, you need to do more for me than just provide comfort care. You need to actually solve my problems. Can you do that, Doctor?
Doctor: I have other patients waiting...

Good luck with that, SU.

Thank you, Doctor.

M.D.Hosehead wrote:Another variety of sleep-related movements are called "hypnic jerks"

How do I distinguish between hypnic jerks and PLMWs? I think a couple of them are normal as you're falling asleep, but I don't know about lots of them...

SleepingUgly wrote: Doctor: What medications are you taking?
Me: I just gave the list to your nurse and she entered them in the computer.
Doctor: I still have to go over them with you.
Me: Why? Don't you think your nurse is competent?
Doctor: These are the rules.
Me: You're going to have to do more for me than just review my list of medications with me each time you see me if you want to save my life, Doctor.
Doctor: Are you dying?
Me: Doesn't it say "DNR" on my chart?
Doctor: No, why would it--
Me: Then, Doctor, you need to do more for me than just provide comfort care. You need to actually solve my problems. Can you do that, Doctor?
Doctor: I have other patients waiting...

Well, ask him what he thinks the prevalence of PLMW's happens to be compared to RLS and PLMs during sleep... I never heard of them before! But sure enough, here they are: http://scholar.google.com/scholar?hl=en ... a=N&tab=ws

P.S. Remember to tell him you're using pseudoephedrine...

You don't distinguish between them - your MD does. I think you need to talk to him or her and they can decide.

SleepingUgly wrote:

M.D.Hosehead wrote:Another variety of sleep-related movements are called "hypnic jerks"

How do I distinguish between hypnic jerks and PLMWs? I think a couple of them are normal as you're falling asleep, but I don't know about lots of them...

I think it's apples and oranges.

PLMW is a finding in a sleep lab; the subject has an awake EEG and repetitive leg movements of some arbitrarily defined frequency and duration.

HJ is a reported symptom. Someone reports that his/her muscles twitch or jump during transition to sleep, not necessarily repetitively and not limited to legs.

If someone with HJ goes to a sleep lab, will he have PLMW? I don't think anyone knows.

I don't think anyone knows what causes the phenomena, whether they are correlated, or what they signify (other than the obvious fact that they may interfere with sleep).

A med or other treatment might help, perhaps something that has worked for RLS, PLM's, a sedative., diet change, stopping Allegra. But you have to decide whether leg movements are causing you enough suffering to want to try any of that, considering how vaguely this is understood.

It's also possible the movements may disappear as mysteriously as they appeared. Perhaps, as you suggest, they will turn out to have something to do with walking, fatigue, or irregular sleep due to travel.

I wish you the best.

Also, the ICSD differential diagnosis for hypnic jerks is outlined on PDF page 86 of 208 here:
http://www.esst.org/adds/ICSD.pdf

While the overall ICSD covers PLMS and PLMD, they don't discuss PLMWs...

As a side note I experience minor hypnic jerks as well... Mine tend to present as slight and few upper body and arm movements.



(on edit: Adobe "PDF page 86 of 208" works out to be page 156 in the above ICSD document)