Peripheral neuropathy can sometimes cause other medical problems, such as foot ulcers, heart rhythm changes and blood circulation problems.
These complications vary depending on the underlying cause of the peripheral neuropathy.
Diabetic foot ulcer
A diabetic foot ulcer is an open wound or sore on the skin that's slow to heal. These are common in people with diabetic polyneuropathy.
If you have numb feet, it's easy to cut your foot by stepping on something sharp.
An ulcer can also come on if you unknowingly develop a blister caused by badly fitting shoes.
If you do not feel any pain, you may continue walking without protecting the blister. If the cut or blister gets worse, it may develop into an ulcer.
High blood sugar can damage your blood vessels, causing the blood supply to your feet to become restricted.
A reduced blood supply to the skin on your feet means it receives a lower number of infection-fighting cells, which can mean wounds take longer to heal and can lead to gangrene.
If you get a wound infection in one of your feet as a result of peripheral neuropathy, there's a risk this could lead to gangrene.
If gangrene does develop, you may need surgery to remove the damaged tissue and antibiotics to treat any underlying infection.
In severe cases, your toe or foot may need to be amputated.
If you have diabetes, you should take extra care of your feet. Get your feet checked regularly by a podiatrist, a medical professional (also known as a chiropodist) who specialises in foot care.
Heart and blood circulation problems
Cardiovascular autonomic neuropathy (CAN) is a potentially serious heart and blood circulation problem that's common in people with diabetic polyneuropathy.
CAN happens when damage to the peripheral nerves disrupts the automatic functions that control your blood circulation and heartbeat.
The 2 main noticeable symptoms of CAN are:
- an inability to exercise for more than a very short period of time
- low blood pressure that can make you feel dizzy or faint when you stand up
You may be able to control the symptoms of low blood pressure by:
- standing or sitting up slowly and gradually
- drinking plenty of fluids to increase the volume of your blood and raise your blood pressure
- wearing compression stockings to help prevent blood falling back down into your legs
- tilting your bed by raising it at the head end
In some cases, you may need to take medicine for low blood pressure. These are most likely to be:
- fludrocortisone, which works by increasing the volume of your blood
- midodrine, which works by tightening your blood vessels
A more serious concern with CAN is that your heart may suddenly develop an abnormal pattern of beating (arrhythmia), which could lead to a cardiac arrest, where your heart stops beating altogether.
You may be prescribed medicine to help regulate the beating of your heart, such as flecainide, beta blockers or amiodarone, to prevent this.
If you have CAN, you'll probably need to have regular check-ups so your heart function can be monitored.