Causes of Left arm numb: Is it a heart attack or anything else?


Numbness is where there is no sensation felt in any area of the body by the individual. Numbness in the left arm can occur as a result of as easy as the position of sleeping or as dangerous as a heart attack. There could be various causes in-middle of the above-mentioned causes. This also includes numb feeling in the right arm. The causes could also vary from carpal tunnel syndrome (hands and fingers get a lot of pain which occurs due to squeezing of the main nerve that passes on the carpal bones via a transit/ movement “at the front of the wrist” to a pinch in the nerve. The reason might be unknown but once treated it helps provide a sense of ease as well as help find the root cause of the issue.

As mentioned above one of the smallest reasons for numbness in the hand or arm could be being in the same position for an extended period i.e. sitting or sleeping. This adds strain on an individual’s nerves and decreases the flow of blood, which results in numbness for a shorter period.

If the feeling of numbness is temporary than the situation is not very alarming or dangerous. The issue will get sorted/solved on its own. If the issue of numbness continues, without any doubt important to inform the physician for the same.

Seek Medical Help

If you get the following symptoms

  • Pain and strain in the chest
  • Pain in the shoulder, back, and jaw
  • Discoloration of the skin
  • Infection and swelling
  • Problems in breathing and gulping/swallowing
  • Indecision or confused
  • Headaches
  • Weakness in one-half of the muscles
  • Nausea and Vomiting
  • Problems in balance and coordination


Decreased blood flow

If there is an issue with the arteries and veins, it can affect the supply of blood to the arms. In-case of medical conditions like diabetes, hypertension, kidney disorders, results in vascular disorders. It could also happen as a result of injury, tumors or any other abnormalities or irregularities. Other than sensations of numbness, pricking/tingling in hands and arms, it also results in pain, swelling, the color of the fingertips is abnormal, hands and fingers getting cold.

The cause of the problem decides the treatment and consists of ways to restore the blood vessels which were affected i.e. ways such as pressure wraps or surgical procedures.

Causes due to trauma
Fracture of the bone

The fracture can result in numbness of the arms. It also causes swelling and pain. Till the healing process is done, the bones need to be relocated and arms need to be avoided from any kind of movement. Depending on the extent of the injury, this is achieved. If the fractures are minor, the treatment is done with a cast or brace only. If it is a major fracture, it might need a proper surgery for alignment and firmness of the bones appropriately.


Numbness could be a result of heat or chemical burn. This is majorly for the burns that go deep inside the skin and affects the nerve endings.

If the burns are minor, treatment can be done at home using cold water. Application of petroleum jelly, when there is a break in the skin. Avoid using any sort of butter or topical steroid treatments as it can result in infections. These parts need to cover with a non-stick bandage, allowing the blisters to heal on its own. In-case if the burns are very major or large, go to the emergency room for treatment or else it could be serious and life-threatening and require proper care.

Bite from Insects

A bite from the insect could have a major allergic reaction and for others, it could result in minor symptoms. This causes numbness or pricking/tingling sensations around the areas which are affected.

Minor bites should be taken care of while washing the part and application of a cool compress. To decrease itching, over the counter histamines are to be used.

If below-given symptoms are observed, take immediate medical attention:

  • Breathing problems
  • Throat, lips, and eye-lids are swollen
  • Cramps, nausea, and vomiting
  • Faster heart-beat
  • Faint sensation or confused
Herniated Disk

If there is a presence of this herniated disk in the neck, it results in symptoms such as numbness, tiredness and a tingling or pricking sensation in the arm. It also results in pain that is radiating such as arm, neck or shoulder.

The treatment is done by proper rest, heat and cold applications, to get relieved by having over-the-counter drugs. If the symptoms for the same continues, consult your physician. There could be a requirement for medicines or surgery.

Brachial plexus nerve injury

These nerves “run down the arms from the spinal cord in the neck.” If the nerves are injured it can block the messages required to be transmitted from the brain to the arms, resulting in a lack of any sensations. This also has an impact on the shoulder, elbow, wrist, and hand.

If the injury is minor it would get better on its own. If the condition is severe it might extend up for weeks or months. Surgery might be required.

Other injuries of the nerve

Excess peripheral (areas do not include brain and spinal cord, but body areas including the muscles and organs) injuries to the nerves result in “pinched nerves” resulting in pain and numb sensation in arms and forearms. This includes:

  • Carpal tunnel syndrome

This results in affecting the “median nerve” in the middle of the ligaments and bones present in the “forearm.”

  • Cubital tunnel syndrome

    This results in affecting the ulnar nerve situated near the elbow.

  • Radial tunnel syndrome

    This results in affecting the radial nerve that is situated starting from arm until the back of the individual’s hand.

These issues/ problems could be made appropriate in ways such as:

  • To avoid any tasks that repeat.
  • To avoid those tasks which include strain to the area which is injured.
  • Surgery.
Degenerative diseases
Cervical Spondylitis

This is also termed as cervical spondylotic Myelopathy. This occurs when there is compression of the spinal cord in an individual’s neck. This results in numbness, weakness or any sort of pain in the arm. Other symptoms consist of pain in the neck and problem using hands or walking. There would be a requirement for “neck brace” or “physical therapy” but in extreme situations, medicines or surgery might be required.

Cervical Spinal Stenosis:

This is a result of the spine getting narrowed in the neck. This could be a result of cervical spondylotic myelopathy. This results in sensations of numbness, prickling, tingling and weak feeling in the arm. This also has an impact on the feet, urinary bladder, and bowel. The treatment is via medicines, “physical therapy” or surgical methods.

Heart Attack

A heart attack also causes numbness in the arm. Other symptoms could include:

  • Pain and strain in the chest
  • Jaw, arm or back pain
  • Breathing problems
  • Dizzy feeling
  • Nausea or vomiting

This issue occurs, when the arterial supply of blood to the area of the brain is interrupted. In some time, the cells of the brain start to die. This affects one part of the body and results in numbness of the arm, leg and lower face. Some symptoms are:

  • Problems in the speech
  • State of confusion
  • Headaches occurring suddenly
  • Vomiting
  • Dizzy feeling, problems in balance and coordination
  • There is an immediate requirement for medical help for people with stroke.
Multiple sclerosis

Initial Symptoms for Multiple Sclerosis include numbness and tingling sensations. Due to numb sensations in your arm, can make it difficult to pick up things. Multiple Sclerosis affects the transfer of signals in the middle of the brain and other parts of the body. Symptoms include problems in coordination and balance, tiredness, dizzy feeling, and vertigo. There is nothing particular for the symptoms as mentioned. Corticosteroids also help to make the sensations in the arm normal.

Vascular Thoracic Outlet Syndrome

At times, there is compression of the nerves and blood vessels in the arms. This results in numbness, pricking, tingling and pain in the arms, hands, and neck. Hands might change into pale blue or the healing of the wound is slowed. It can be treated with medicines, physical therapy and if required surgery.

Peripheral Neuropathy

Numbness could be a result of peripheral neuropathy. This results in the peripheral nervous system being damaged. Other symptoms include sensations of tingling or burning, weakness in the muscles, on touch provides reactions that are not normal. Other symptoms that are at the extremes are wasting of the muscles, paralysis of the local area and dysfunctioning of the organs. This could be a cause of medical conditions such as diabetes mellitus, hormone or deficiency of vitamins and toxins. Depending on the cause, the treatment is done.


An increase in the blood sugar levels can affect the nerves and results in diabetic neuropathy. In this condition, there is an occurrence of numbness in both the feet. In rare situations, it has an impact on your hand. If an individual is suffering from diabetic neuropathy, it causes tingling or burning sensations, pain or cramps which are sharp, touch increases the sensitivity, weakness of the muscles, In the ankle there is loss of reflexes, Problems in balance and coordination, problems in the foot such as ulcers, infections, pain in the joint and bone. Treatment is to control blood sugars, take medicines as prescribed and focus on healthy lifestyle changes.

Deficiency of Vitamin B12

Vitamin B12 could also result in peripheral neuropathy. This also leads to the development of anemia. Damage to the nerves causes other symptoms such as:

  • Numbness, tingling or pricking sensations along with pain in the hands and feet.
  • No proper coordination
  • Loss of senses
  • General tiredness and fatigue
  • Treatment is to increase B12 in the diet via foods such as dairy products, eggs, fish and others. Even supplements could be taken to restore the levels of vitamin B12.
Wernicke Korsakoff Syndrome

This is also caused due to peripheral neuropathy. This syndrome occurs due to a deficiency of Thiamine (Vitamin B1) deficiency. Symptoms consist of confusion, disorientation. The treatment is done by thiamine replacement therapy, avoiding alcohol and improving the diet.

Headache due to Migraine

There is a temporary weakness on one side of the body that occurs in hemiplegic migraine. It can result in the arm get numbed and develop feelings like that of pins and needles. Migraine results in causing one-sided pain in the head, nausea, and sensitivity to light. Migraine is treated with medicines.

Lyme disease

This disease is caused due to bacteria. If left untreated it causes numbness in the arm. It also causes “shooting pains” and/or tingling sensations. Other symptoms include irritation of the skin at the “site of the tick bite or bull’s eye rash”, pain in the head or dizzy sensations, muscle weakness on one part of the face, bone pain and muscle joint pain. This disease could be treated with antibiotic therapy.

Lead Poison

If exposed to excessive amounts of lead it results in numbness of the “extremities.” Other symptoms include weakness of the muscle, pain, nausea, vomiting, the taste of metal in the mouth, loss in weight and decrease in the appetite, damage to the kidney. When poison due to lead is in excess, chelation therapy is used to remove lead from the body.

Side-effects of chemotherapy

Certain kinds of chemotherapy for cancers causes damage to the nerves that results in numbness/tingling/pricking in arms, fingers, toes, legs or other parts of the body. This feeling or sensation is termed as “glove and stocking sensation” as the feeling is like a “thick tight glove.” Treatment for this is to take medicines to avoid pain.

Few ways to treat with numbness of the arms

  • If suffering from numbness in the morning, try to work on the position of sleep. Avoid sleeping on the arms.
  • Try working on simple movements throughout the day to improve blood circulation and avoiding numbness of the arms.
  • Avoid continuous movement of the arm, leg, shoulder, wrist and finger movements. Try to take in-between breaks to break the pattern and excess strain on the body.
  • If arm numbness is affecting the work or any other daily routine, do consult a physician for the same. The cause decides the treatment. Symptoms may be relieved if the underlying cause or condition is treated.



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