There are many causes of numbness in your toes and feet, including problems with blood flow that disturb the nerves in your feet, damage to the nerves that supply your feet, and diseases of the body that affect your nervous system. You should be worried about numbness or tingling in your toes or feet if the numbness does not go away, keeps coming back, or if it occurs along with other symptoms.
Pins and needles or tingling in feet
The feeling described as “pins and needles” or tingling in your feet is called paresthesia. You may have also heard or used the term “falling asleep,” as in my foot fell asleep. Paresthesia symptoms may also include the sensations of burning, skin-crawling, or numbness. Paresthesia often occurs in the feet and toes, but can also occur in the arm and hand.
The most common cause of a paresthesia that goes away is a temporary decreased blood supply to your lower legs. This can happen if you sit for a while or fall asleep with your legs crossed. As blood supply slows down and your nerves are not getting enough oxygen, they stop sending nerve signals to your spinal cord. When you get up or roll over, a rush of blood supply causes the nerves to start sending signals in a rush, and you feel pins and needles. This feeling goes away quickly and is not dangerous.
Pins and needles, tingling, and numbness that does not go away or keeps coming back
Pins and needles, tingling, or numbness that does not go away once you start moving may be a more serious problem, and there are many possible causes. One very common cause is diabetes. Diabetes affects the blood supply to your feet because it causes damage to small blood vessels that carry oxygen, called diabetic neuropathy. Diabetes is the most common cause, but other conditions also cause damage to nerves that supply the feet, called peripheral neuropathies. Vitamin B deficiency, alcohol abuse, and chemotherapy are just some examples.
A pinched nerve in your lower back is also a very common cause. A nerve that leaves your spine and runs down your leg to supply your foot can be pinched or squeezed by a bulging spinal disc (the cushion between spinal bones) or an outgrowth of spinal bone due to arthritis, called a spur. Pressure on the nerve interferes with nerve signals that travel to your foot. Unlike diabetic neuropathy that usually affects both feet. A pinched nerve usually affects just one foot. If you also have pain shooting down your leg it is called sciatica.
The other major cause of pins and needs or numbness in your feet is a systemic disease or condition, meaning it affects your whole body. Systemic conditions can affect your nervous system in many ways. They can cause a wide range of symptoms from tingling, pins and needles, or numbness, to pain, weakness, dizziness, or weakness. They include:
- Circulation problems, called peripheral arterial disease, usually due to atherosclerosis
- Blood clots in your leg
- Peripheral nerve injuries
- Kidney disease
- Vitamin B deficiency
- Alcoholism
- Raynaud’s disease
- Migraine headaches
- Anxiety or panic attacks
- Seizure disorders
- Herpes or HIV virus infection
- Side effects from chemotherapy or other drugs
- Central nervous system (brain and spinal cord) trauma or tumors
- Stroke
- Blood mineral (electrolyte) imbalance
- Lead poisoning
Multiple sclerosis (MS), rheumatoid arthritis (RA), Guillain-Barre syndrome (GBS) and, systemic lupus erythematosus (SLE) can all cause tingling and numbness along with other symptoms. Thay are all autoimmune diseases that occur when the body’s defense (immune) system attacks the nervous system.
Is foot numbness dangerous?
It depends on the cause. Most cases are not life threatening, but may need to be treated. Some clues that numbness, tingling, or pins and needles need to be evaluated by your health care provider include: The pattern of the sensation is similar on both sides (bilateral and symmetric). This suggests a systemic cause.
- Sudden onset indicates nerve injury.
- Gradual onset suggests a systemic cause.
- Symptoms that come and go could indicate blood flow interruption or circulation or nerve compression.
- Pain suggests a pinched nerve or diabetic neuropathy.
- Weakness could be systemic illness such as MS.
- Cold or color changes to the extremities indicate circulation concerns.
- Pain that occurs when you put your feet up pr lie down, indicates circulation concerns or spinal nerve compression.
How do doctors diagnose this condition?
Your doctor will take a full history of your foot or feet symptoms, how long they last, if they start suddenly or gradually, and any other symptoms you have. Other keys to the diagnosis include:
- A nervous system (neurological) exam
- A blood flow (circulatory) exam
- A muscles and bone (musculoskeletal) exam
- Blood tests and other laboratory tests
- Imaging studies
- Nerve conduction studies
There are many possible treatments available once the cause is found. Treatment could be as simples as rest and wearing supportive shoes when walking. Medications, physical therapy, and sometimes surgery are other possibilities.
When should you call your doctor?
You don’t have to call your doctor if you have an occasional episode of pins and needlers, but any pins and needles, tingling, pain, or numbness that is not going way or keeps coming back should be evaluated. You should call your doctor when symptoms do not resolve or worsen with rest.
