The “falling asleep” of the arm usually refers to harmless temporary numbness and/or tingling. If the arm occasionally falls asleep and there are no further complaints, the cause is often without any disease value. But numbness and tingling in the arm can also indicate diseases that require treatment. If one arm or both arms “fall asleep” more frequently or if the sensations no longer recede, a doctor should be contacted.
Causes of falling asleep arm
There are various causes for “falling asleep” arms. One can distinguish between causes without disease value and causes with disease value. Short-term irritation of certain nerves can lead to short-term sensations and numbness in the arm.
These are usually harmless. Imbalances, tensions and tenseness of various muscles in the neck and arm area can temporarily compress one or more nerves. This irritates the nerves and causes temporary sensations of discomfort.
As a rule, no (medical) treatment is required. However, diseases such as multiple sclerosis, a herniated disc or migraine with aura can also provoke one or both arms to “fall asleep”. These diseases must be differentiated and treated by a doctor.
Furthermore, certain deficiencies (e.g. vitamin deficiency), diabetes mellitus, alcohol abuse, certain medications or infections can cause tingling and numbness in the arms. These causes also require medical support. If a sudden numbness is accompanied by paralysis and cannot be attributed to it, emergency medical assistance should be sought directly.
In case of an inability to move the arm, to grasp something specifically, hemiplegia and/or suddenly occurring speech disorders, a stroke should always be ruled out by a medical specialist. A deficiency of certain vitamins and nutrients can result in sensations. These usually manifest themselves in the hands or feet.
In some cases, these nervous disorders can also occur in the arms as a deficiency symptom. A vitamin B12 deficiency in particular can imply that the hands and feet, and possibly the arms, fall asleep. But an imbalance of other nutrients and a deficiency of iron and/or magnesium are also potential triggers.
If these nervous disorders are caused by a vitamin deficiency, they may result in weakened muscle strength, sensitivity and coordination disorders, and even paralysis. Vitamin B 12 deficiency particularly affects older people. To what extent a vegetarian or vegan diet plays a role in this context is controversially discussed.
However, a vitamin B12 deficiency is often not recognised. In about 25% of all cases, the deficiency symptoms appear without a deficiency being detected in the blood count. A functional vitamin deficiency can definitely exist despite normal blood values.
This can be proven by measuring the connection of vitamin B12 with a binding protein. This compound is called holo-transcobalamin (Holo-TC). If the cause of the “falling asleep” arms is a vitamin deficiency, it should be examined and treated by a doctor.
A stroke can manifest itself in many different ways. Depending on which area of the brain is affected, the body may suddenly stop working. This can affect motor skills, thinking and acting as well as sensitivity.
This can also result in sudden sensitivity disorders, movement disorders and hemiplegia of one arm. Often – but not necessarily – other complaints occur in addition to the disorders concerning the arm. If there is a suspicion that a stroke has triggered the symptoms, an emergency doctor should be called immediately.
It is quite possible that the affected person himself does not notice the disorders or cannot react adequately. If relatives suspect that a stroke has been diagnosed, medical clarification should be arranged as soon as possible. The earlier a stroke is treated, the better the prognosis.
Multiple sclerosis can cause nervous disorders of various kinds. Theoretically, these can therefore also manifest themselves in the form of the arms falling asleep. Multiple sclerosis causes inflammation and breakdown of the insulating discs of the nerve cells.
These are also known as myelin sheaths and are located at various points in the central nervous system. Therefore, the disorders and their course can manifest themselves in very different ways. According to current statistics, sensory disturbances of the arms and legs are the most common initial symptoms.
About 30-50% are affected. The second most common symptom is impaired vision. About 20% of patients who show this initial symptom are in a young age.
The third most common symptom is muscle dysfunction, including in the arms, but also in the legs. These can manifest themselves as increased muscle stiffness, lack of strength or paralysis. Often there are parallel disturbances of balance and coordination.
If the arms are affected, specific gripping and fine motor functions may be restricted. If the legs are affected, standing insecurities and gait disorders can develop. In addition, other complaints can occur, such as abnormal fatigue, a micturition disorder, intestinal voiding disorders, sexual disorders, disturbed, altered articulation and psychological disorders.
In the case of a heart attack, some affected persons report a radiating pain in the left arm. These complaints are usually described more as pain and less as a “falling asleep” of the left arm. However, as the perceptions and descriptions vary greatly, this should be taken seriously. In particular, if chest pain or heart problems also occur, heart examinations should be performed.