Peripheral Neuropathy

What is it?

Peripheral neuropathy means damage to one or more of the nerves outside your brain and spinal cord. "Peripheral" simply means "outer". These nerves carry feeling from your skin and tell your muscles to move. They also help control body functions such as blood pressure.

It most often affects the feet, legs, hands and arms. Most people have polyneuropathy, which means several nerves are affected. It usually happens on both sides of the body. It often starts in the toes and slowly moves up the leg, because the longest nerves are affected first.

Who does it affect?

About 1 per cent of adults have peripheral neuropathy. It is much more common in people with diabetes. Estimates range from about 36 per cent to about half of people with diabetes. Among people with diabetes, about 10 to 20 per cent have symptoms bad enough to need treatment.

In people with diabetes, the risk is higher if you have had diabetes for longer, are older, or have a higher HbA1c (a blood test that shows how well your blood sugar has been controlled over time). Diabetic retinopathy (eye damage from diabetes) and chronic kidney disease also raise the risk.

Signs and symptoms

Symptoms can be mild or severe. Common ones are:

• numbness or tingling in your feet or hands, or pins and needles
• burning, stabbing or shooting pain, often worse at night
• being oversensitive to touch
• not feeling pain, or not noticing hot and cold
• poor balance and co-ordination
• weak muscles, especially in the feet

If the nerves that move your muscles are affected, you may find it hard to lift the front of your foot and toes when you walk (this is called foot drop). Weakness can also lead to falls and changes in the shape of your toes or feet. Some people feel dizzy or faint because their blood pressure isn't well controlled.

The changes can be very gradual, so you may not notice them at first.

The biggest risk is that you can't feel injuries. You might step on something sharp, or pick up something too hot, and not know. A small injury that goes unnoticed can become infected, and this is more common and more serious in people with diabetes.

What causes it?

Diabetes is the most common cause. Other common causes are:

• low vitamin B12
• heavy alcohol use, especially over a long time
• kidney problems
• some chemotherapy drugs

Neuropathy can also be inherited, for example in Charcot-Marie-Tooth disease. Sometimes the cause isn't found.

If you have diabetes, your neuropathy may have another cause as well. Low vitamin B12 or vitamin D, a lot of alcohol, and an underactive thyroid (hypothyroidism) can all play a part. Neuropathy from chemotherapy tends to be worse with several drugs, longer treatment and higher total doses. It is also worse if you have diabetes, drink a lot of alcohol or have low vitamin B12.

How is it diagnosed?

Your doctor or podiatrist will ask where you feel symptoms, whether both sides are affected, and whether pain is worse at night. They will also ask about balance, weakness, diabetes, alcohol, medicines (including chemotherapy) and kidney problems. A foot check looks at how well you can feel things, and may include a blood test to look for a cause.

If you have diabetes, you should have regular foot screening. It checks for loss of protective sensation (not feeling enough to protect your feet from injury) and for peripheral artery disease (poor blood flow to the legs and feet). Your podiatrist can do these checks.

Treatment

Treatment depends on the cause. The main aim is to protect your feet from injury and infection.

Looking after it at home

Check your feet every day for cuts, blisters, sores or redness. Use a mirror, or ask someone to help, if you can't see the soles of your feet.

Always wear sensible, supportive shoes or boots, and don't walk without foot protection. If you have prescribed footwear or insoles, wear them as much of the time as you can. Take extra care around hot things, because you may not feel a burn.

Treatment from your podiatrist

If you have diabetes and feel less in your feet, your podiatrist can check your feet regularly. They will teach you how to look after your feet and why you should never walk without foot protection. They can also treat early skin damage that could turn into a sore (an ulcer), and advise on supportive shoes and insoles.

Other options

If you have nerve pain, medicine choices are made with your doctor or prescriber. If treatment isn't helping, go back to your doctor to review the cause and the options. Keep protecting your feet in the meantime.

If you notice neuropathy during chemotherapy, speak to your doctor. They may consider delaying, reducing, changing or stopping the drug. Don't change your treatment on your own.

If you have Charcot-Marie-Tooth disease, your doctors will avoid medicines that can harm nerves, such as vincristine and cisplatin, where they can.

Recovery

How your nerves do over time depends on the cause, and your doctor can tell you what to expect in your case. Seeing a doctor early gives you a better chance of limiting the damage and avoiding problems.

The problems to watch for are injuries, burns and infections you don't notice, and falls. If you have diabetes, good blood sugar control and healthy kidneys matter. Both were linked to whether people developed new nerve damage.

Preventing it

You can't prevent every cause. If you have diabetes, you can lower your chances of new nerve damage by keeping your blood sugar well managed and looking after your kidneys. Talk with your diabetes team about how to do this.

You can also prevent the problems that nerve damage brings. Check your feet daily, wear supportive footwear, and have your feet screened regularly.

When to see a podiatrist

Book an appointment if

You have new numbness, unusual tingling, weakness, loss of balance, or pain or burning in your hands or feet: see your GP soon, because earlier diagnosis gives a better chance of limiting damage. If you have diabetes, keep up your regular foot checks with your podiatrist or GP.

Seek prompt assessment if

Call your local emergency number if your symptoms come on suddenly and get worse quickly, for example weakness that spreads fast or trouble breathing. If numbness, tingling or weakness is getting worse over days, see your GP or another doctor today. If your GP can't see you today, go to an urgent care clinic or an after-hours GP. If you have a cut, sore or blister on your foot that isn't getting better, see your podiatrist or GP soon. If you have a foot wound or infection and you also feel very unwell, with confusion or slurred speech, severe shivering or muscle pain, severe breathlessness, mottled or discoloured skin, or little or no urine, this could be sepsis: call your local emergency number. If neuropathy symptoms start during chemotherapy, speak to your doctor soon.

Frequently asked questions

Can I have neuropathy without diabetes?

Yes. Many people with the common foot-and-leg pattern have a cause other than diabetes, such as alcohol, kidney problems or some medicines. Doctors find a cause in about 7 in 10 people after a history, examination and blood tests. In about 3 in 10 people, no cause is found.

Should I get my vitamin B12 checked?

If you have diabetes and neuropathy, checking your vitamin B12 is considered an essential part of the work-up. Low or borderline B12 is common in people with diabetes who have nerve damage. Ask your GP whether yours has been checked.

Does neuropathy make me more likely to fall?

Yes. Poor balance and weak muscles can lead to falls. People with diabetic neuropathy are two to three times more likely to fall than people with diabetes who don't have neuropathy. See your GP early if you notice new balance problems or a fall.

How often should I have my feet checked?

If you have diabetes, have your feet screened at least once a year by your GP, practice nurse or podiatrist. People at higher risk of foot ulcers need checks more often. Nerve changes can be gradual, so you may not notice them yourself.

Further reading

• What Is Peripheral Neuropathy? Cleveland Clinic
• Peripheral neuropathy - Treatment NHS
• Peripheral Nerve Disorders MedlinePlus