What Causes Numbness in Right Arm?

Numbness in your right arm can happen for a wide variety of reasons. Usually, it can be written off to inactivity and uncomfortable sleeping positions. It can also be caused by vitamin B-12 deficiency.

Sometimes, numbness in your right arm is a sign of carpal tunnel syndrome. However, aside from CTS, multiple sclerosis, cervical radiculopathy, and peripheral neuropathy are also known to cause numbness in hands, forearms, and upper arms.

Also, diseases and conditions such as diabetes, blood clots, varicose veins, obesity, and rheumatoid arthritis can cause nerve damage and numbness. Keep reading for a thorough analysis of the causes of numbness in right arm.

Poor Circulation and Lack of Movement

Sometimes, the numbness in your right arm can happen as a result of a lack of movement or poor circulation. If you have held your right arm in one position over a prolonged period of time, it might go numb and (or) start to tingle. Commonly, this happens if you had your hands behind your back while lying on your back or if you slept in an uncomfortable position.

If a lack of movement is the cause of numbness, you should start moving your right arm slowly. This will allow the blood to start flowing through the arm and to its nerves.

However, if poor circulation is causing numbness and/or tingling, it might mean that you are suffering from one of the following diseases and conditions:

  • Blood clots. Blood clots or thrombus can form virtually anywhere in your body, including your right arm. They are tiny clumps of blood that can be life-threatening if they reach your heart or brain. When they are stationary, they aren’t that much of a threat, but once they break off and start moving through veins and arteries, they can cause a lot of damage.
  • Varicose veins. These are thick veins, visible under your skin. Blood doesn’t move through them as well as healthy veins, which can cause a variety of problems. If they’re found in your right arm, they can also cause numbness.
  • Peripheral artery disease. It is caused by the narrowing of arteries which, in turn, diminishes blood flow to your extremities. Reduced blood flow can cause numbness.
  • Diabetes. Diabetes can cause poor circulation, as it can potentially damage your blood vessels. And blood vessels with reduced ability to circulate blood can cause numbness.

Carpal Tunnel Syndrome

Carpal Tunnel Syndrome (also referred to as CTS) is one of the most common causes of pain, tingling, and numbness in your hands and forearms (it can happen on either side). The syndrome is caused by an irritation or compression of the median nerve which passes through the carpal tunnel, a passageway located on the palm side of your wrists.

There are many causes of CTS, most common of which include:

  • Wrist fracture
  • Obesity
  • Diabetes
  • Other chronic illnesses
  • Repetitive hand motions
  • Fluid retention
  • Rheumatoid arthritis

CTS is usually treated with corticosteroids, NSAID (non-steroidal anti-inflammatory drugs), and wrist splints (used to fix the wrist in one position). Also, in cases of severe CTS or if the other treatments aren’t effective, surgery is used to relieve the symptoms.

Cervical Radiculopathy

Cervical radiculopathy, also known as pinched nerve, is another common cause of numbness in right arm. It is commonly caused by irritated neck nerves. A range of injuries and aging can cause a herniated or bulging intervertebral disk. The most common symptoms include:

  • Tingling and numbness in fingers, hand, and arm
  • Loss of sensation in fingers, hand, and arm
  • Muscle weakness in hand, arm, and shoulder

Typically, symptoms of cervical radiculopathy go away on their own in a matter of days or weeks. However, if they persist, your doctor might prescribe one or a combination of the following: NSAIDs, physical therapy, steroid injections, surgical collar, and oral corticosteroids. If the non-invasive treatments fail, surgery might be in order.

Multiple Sclerosis

Multiple sclerosis (MS) is a degenerative disease that damages the nerves and their insulating covers in the brain and spinal cord. It is another common cause of numbness and/or tingling in your right arm. The numbness and tingling can also affect other parts of your body if you suffer from MS. Symptoms might include:

  • Tremor
  • Fatigue
  • Pain and tingling in different parts of the body
  • Double vision
  • Dizziness
  • Slurred speech
  • Loss of vision, total or partial
  • Weakness and numbness in arms (commonly affects only one side)

At the moment, there is no known cure for multiple sclerosis. Instead, the treatments are designed to manage the symptoms and impede the progress of the disease.

In addition, patients suffering from MS are usually prescribed a balanced diet and exercise.

Peripheral Neuropathy

Peripheral neuropathy is caused by damage to the peripheral nerves in your body. Its most common symptoms include tingling, burning, or stabbing pain in hands, arms, feet, and legs. Numbness may also occur. Typically, the symptoms start in the hands and feet and progress up to the arms and legs.

Many illnesses and conditions may cause peripheral neuropathy. The most common ones include alcoholism, kidney and liver diseases, connective tissue disease, diabetes, trauma, spider and insect bites, tumor, infections, alcoholism, and autoimmune diseases.

As it is often caused by other diseases and conditions, treatment of peripheral neuropathy is often conducted in conjunction with that of the underlying disease or condition. Peripheral neuropathy-specific drugs might include various antidepressants, NSAIDs and other OTC pain relieving drugs, as well as anti-seizure drugs.

Vitamin B Deficiency

In some cases, a lack of vitamin B-12 can cause nerve damage. In turn, the damaged nerves might cause your right arm to tingle and grow numb. Typically, you will first get vitamin shots. If that fails, you might get supplements, to be taken over a period of time. To keep the level of vitamin B-12 at a proper level, make sure you eat enough seafood, milk and dairy products, poultry, eggs, and meat.


While certainly unpleasant and potentially frightening, numbness in right arm is often a result of a momentary reduction in blood flow. Apart from inactivity, it can be caused by a host of other health problems and conditions.

If you feel numbness in your right arm, simply stretching your arms should be enough to get the blood flowing and regain sensation. In case the numbness persists and/or is accompanied by stabbing pain, crawling sensation, or burning pain, you should go see a doctor.