In some cases, left arm pain and numbness may indicate a heart attack or stroke. These medical emergencies require immediate attention. However, there are other causes of left arm pain and numbness that do not need emergency help.

This article discusses when to call 911 about left arm pain and numbness, and some other possible causes of the problem.

When to call 911

Many cases of left arm pain and numbness are not a cause for concern. But these symptoms can also be the signs of a medical emergency, such as a heart attack.

People must call 911 if other symptoms of a heart attack occur that include:

  • pressure or pain in the chest
  • pain in other areas of the upper body, such as the neck and back
  • shortness of breath
  • cold sweat
  • nausea
  • lightheadedness

It is also essential to call 911 for a stroke, which may include other symptoms, such as sudden:

  • numbness in the face, arm, or leg on one or both sides of the body
  • confusion
  • difficulty walking
  • severe headache
  • difficulty seeing

Other reasons for left arm pain and numbness can include the following:

1. Poor circulation

Poor circulation can occur from disruptions to blood flow.

Pressure on a blood vessel can restrict blood flow to the limbs and cause numbness in the arms.

Other symptoms of poor circulation include:

  • cold hands and feet
  • swelling in the limbs
  • tiredness
  • joint and muscle pain
  • digestive problems
  • changes to skin color, such as a blueish tint

One cause of poor circulation can be sleeping in an awkward position. Other causes are more serious.

For example, poor circulation can be a sign of blood or heart disease and diabetes.

Lifestyle factors can also affect circulation, such as smoking and having excess weight. Smoking can result in severe blood flow complications.

Treatment

If the cause is sleeping in an awkward position, symptoms will typically go away on their own.

A person can also make other necessary lifestyle changes, such as:

  • quitting smoking
  • maintaining a healthful diet
  • becoming more active

These lifestyle changes can help to alleviate the symptoms and improve blood flow.

However, if poor circulation is due to other medical conditions, such as heart disease, a person must see a doctor.

Treatment for heart disease depends on the type a person is experiencing.

A person can learn more about the different types of heart disease and their treatment options here.

Treatment for diabetes also depends on the type of diabetes a person has.

2. Pinched nerve

“Pinched nerve” is a colloquial term that describes damage to a nerve, or a set of nerves.

This can affect a nerve that runs down the left arm, causing numbness and pain in the area.

Other symptoms may include difficulty moving the arm and pain that radiates outwards. A person may also experience a burning sensation and “pins and needles,” or tingling.

Treatment

Some cases are treatable at home. For example, a person can avoid repetitive tasks that might be the cause of a pinched nerve.

Treatment might also involve physical therapy to improve strength and flexibility in the arm.

A doctor may also recommend anti-inflammatory drugs to help with the pain.

 

3. Peripheral neuropathy

Peripheral neuropathy is where a peripheral nerve is damaged.

Several conditions can cause this damage, including:

  • trauma
  • diabetes
  • autoimmune diseases
  • hormonal imbalances
  • kidney or liver diseases
  • chemotherapy
  • infections
  • cancers
  • nutritional imbalances

The condition can affect the left arm, causing numbness and pain. There may also be muscle weakness and cramping in the area.

Peripheral neuropathy can also affect other nerves around the body, including sensory and autonomic nerves. This can cause a wide range of symptoms, depending on which nerves experience the damage.

Treatment

Treatments for peripheral neuropathy vary, depending on the underlying cause.

In some cases, a doctor might suggest specific treatments. For example, they might suggest taking painkiller medications or using supportive gear, such as a brace.

4. Cervical spinal stenosis

Cervical spinal stenosis is the narrowing of the spinal canal. The spinal canal is a hollow area between the vertebrae, the bones that make up the spine.

A narrowing of the spinal canal can affect nerves running down the arms.

Cervical spinal stenosis causes numbness and pain around the upper body, including the arms.

It also causes:

  • muscle weakness
  • stiffness
  • difficulty moving or balancing
  • loss of bowel and bladder control

Treatment

Doctors will usually prescribe medications to help with the pain.

Physical therapy or exercises can help to strengthen the arms and improve flexibility.

In severe cases, surgery may be necessary to reduce pressure on the nerves.

Trauma to the left arm can cause numbness and pain in the area.

Different types of trauma that might occur are:

  • bone fractures
  • burns
  • insect bites
  • strains and sprains

Other symptoms can occur, depending on the type of trauma. For example, infected insect bites can cause inflammation, fever, and changes in heart rate.

Treatment

The treatments will also depend on the type of trauma. Some traumas may require medical attention, such as a bone fracture or a moderate-to-severe burn.

A doctor will provide painkiller medications in most cases. A period of rest will likely be necessary for a bone fracture, strain, or sprain.

6. Hemiplegic migraine

According to the National Organization for Rare Disorders, a hemiplegic migraine is a rare disorder. A person will experience a migraine headache alongside weakness on one side of the body.

Hemiplegia can affect one part of the body, such as the hand and arm, or the face.

Other possible symptoms include:

  • an aura, including physical and sensory changes before a headache
  • nausea
  • vomiting
  • difficulty moving
  • sensitivity to light
  • sensitivity to sound
  • lack of muscle coordination
  • fever

Treatment

According to the American Migraine Foundation, a doctor may recommend:

  • nonsteroidal anti-inflammatory drugs (NSAIDs)
  • antiemetics, which prevent vomiting
  • narcotic analgesics

To help prevent hemiplegic migraines, a doctor may prescribe:

  • amitriptyline
  • topiramate
  • valproic acid

Multiple sclerosis is a chronic condition that affects the central nervous system.

It causes the fatty sheath around nerve fibers to break down and become inflamed.

Multiple sclerosis can cause numbness, tingling, and pain in the arms. It can also lead to:

  • tiredness
  • dizziness
  • sexual dysfunction
  • bladder and bowel problems
  • muscle weakness
  • muscle spasms
  • difficulty moving
  • vision problems
  • tremors
  • learning and memory problems

Treatment

Several treatments slow the progression of the disease. For example, a doctor may prescribe disease-modifying therapies, which are medications that target the immune system.

They may also prescribe a range of other medications, such as corticosteroids or painkillers.

Treatments will depend on the severity and type of symptoms.

When to see a doctor

Some causes of left arm pain and numbness do not require a doctor. For example, symptoms with poor circulation from sleeping in an awkward position will go away on their own.

But other causes do require a doctor. An individual can see a doctor if they experience any numbness or pain that persists and has no obvious cause.

For cases where sudden symptoms of a heart attack or stroke occur, it is essential to contact 911 immediately.

Summary

There are many possible causes of left arm pain and numbness. Some cases will require a trip to the doctors, whereas others do not typically require medical treatment.

In some cases, the pain and numbness could be a sign of a heart attack or stroke that requires immediate medical assistance.