You wake in the middle of the night or early morning to find that your arm feels like a lifeless log: numb and asleep. You also have MS and wonder if there’s a connection.
To some individuals, wakening to the dead sensation of an arm that’s “fallen asleep” is unnerving (no pun intended). It’s so numb to the touch that it feels like it belongs to someone else’s body.
This phenomenon can happen to perfectly healthy people when the arm ends up in certain positions that compress nerves. But can multiple sclerosis – an autoimmune disease – also play a role?
The MS Connection to Arms that Fall Asleep at Night?
“People with MS often develop the sensation of pins and needles in their extremities like they are ‘falling asleep,’” says Mitzi J. Williams, MD, clinical neurologist with Morehouse School of Medicine, an MS specialist and clinical advisor for the Multiple Sclerosis Foundation.
“This symptom of nerve dysfunction is called paresthesia and can occur in one or both arms or legs.
“This occurs frequently in several neurologic conditions including MS, diabetic neuropathy and vitamin B12 deficiency.
“With most of these conditions, the tingling can occur at any time throughout the day. With MS, people notice their symptoms are worse at night because they are still and trying to rest.
“However, it is not as common that people with MS actually have the onset of paresthesias at night. This is more common with carpal tunnel syndrome or with sleep positions that compress the peripheral nerves.”
If you’ve been diagnosed with multiple sclerosis and are experiencing a fallen asleep arm at night … it’s very possible that the cause is nothing more than a sleep position.
Or, you just might have carpal tunnel syndrome (which is not related to MS).
Symptoms of Carpal Tunnel Syndrome
• Numbness or tingling in the fingers or hand that’s not always related to sleep position; can happen during the day.
• The pinky is excluded.
• The numbness or tingling may affect the wrist and forearm, and may especially occur while you are holding something or performing repetitive motions like typing.
• The sensation makes you want to “shake out” your hand.
• The hand may be weak.
• There may be wrist pain.
Sleep Time Nerve Compression
Dr. Williams explains, “The arms fall asleep at night because there is increased pressure on the nerves, and this is usually improved with changing positions.”
Next time this happens to you, simply change position (make sure the arm is not pressed up against anything) and just wait it out.
There is no need to shake out the arm or continuously move it to reverse the numbness – unless that feels better.
“If symptoms are due to carpal tunnel syndrome, your doctor can prescribe neutral position wrist splints to decrease the nighttime symptoms.
“If symptoms are severe and not relieved with wrist splinting a surgical procedure may be needed to relieve the symptoms.”
In summary, the issue of an arm or hand falling asleep at night (that’s relieved by change in position) is much more likely to be related to sleep position or carpal tunnel syndrome than multiple sclerosis.
Dr. Williams is author of “MS Made Simple: The Essential Guide to Understanding Your Multiple Sclerosis Diagnosis.” She is a member of the American Academy of Neurology.
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.