Various symptoms in the body can occur without there being any underlying disease. These symptoms may sometimes arise with momentary physiological changes in the body and resolves on its own. Burning feet is one of these types of symptoms and in many cases it may occur with no underlying disease. However, there are instances where burning of the feet is due to a medical problem.
Meaning of Burning Feet
Burning feet is a sensation that the feet are very hot or in very close proximity to a heat source. It is often intense to the point that it feels like a burning pain and may affect daily functioning in various ways. Some people may find it difficult to walk or stand for long periods. Others may have difficulty sleeping due to the burning sensation.
A burning sensation is usually an indication of inflammation, which is the body’s response to tissue injury. However, this is not always the case as sometimes the nerves that carry these signals may be diseased. Therefore the burning sensation arises ‘incorrect’ signals rather than actual tissue injury.
Similarly a sudden change in blood flow to an area may sometimes give the sensation of heat. When the blood vessels on the skin surface suddenly dilates, the blood flow to the area increases. With blood being warm, there is a sensation of heat on the surface, which may be perceived as burning in nature.
Causes of Burning Feet
Exposure to heat, such as when the feet are close to a fire or an electric heater, will naturally lead to a burning sensation if the heat source is intense or there is a prolonged period of exposure. Therefore this cause is not discussed in detail. By removing the heat source or exposure to it, the burning sensation should subside provided that there is no tissue injury.
Mechanical, chemical and electromagnetic injury can all cause a burning sensation in the feet. Apart from burns, other mechanical injury such as blunt or sharp force trauma can both lead to a burning feet sensation. Chemicals that are caustic and damage the skin such as acid can also be responsible. Electromagnetic injury is mainly due to sunburn, where the UV light in intense sunlight or tanning booths damages the skin surface.
A number of different infections of the feet may also cause a burning sensation. Bacterial infections of the skin, like impetigo, or deeper in the subcutaneous tissue (cellulitis) may present with burning pain among other reasons. Another infectious cause of burning feet is athlete’s foot (tinea pedis). This is a superficial fungal infection of the skin on the feet and is very common. Symptoms like burning feet may also be seen with systemic infections such as HIV infection, even when there is no localized infection of the feet.
Environment and Toxins
Environmental factors like cold exposure can also cause burning of the feet. Frostbite is often associated with numbness of the affected area but initially there may be burning as well as when the area is warmed up. Exposure to various toxins can also cause a burning sensation. Lead and mercury exposure are such examples although this does depends on the quantity and duration of exposure, as well as the point of contact.
Nerve Injury and Disorders
There are a number of nerve problems that can present with a burning sensation. The term peripheral neuropathy describes a range of nerve diseases and disorders that involves nerves outside of the brain and spinal cord.
- Nerve compression (pinched nerve) where there is impingement on the nerve. This commonly occurs at the nerve root arising from the spine, like in sciatica.
- Nerve injury can arise in various ways. It may at times be chemical in nature but is often mechanical, like with nerve compression, blunt and sharp force trauma as well as with a partially severed nerve.
- Diabetic neuropathy is a complication of long standing and often poorly managed diabetes mellitus. The elevated blood glucose levels causes nerve damage over time.
– Guillain-Barre syndrome
– Multiple sclerosis
– Charcot-Marie-Tooth disease
– Alcoholic neuropathy
A burning sensation may also be associated with leg conditions where blood circulation is impaired. Insufficient oxygen-rich blood can lead tissue inflammation known as ischemia. Peripheral arterial disease (PAD) is one circulatory condition where this may occur. It is due to narrowing of the artery in the legs due to atherosclerosis. Burning feet may also be experienced with vein problems like varicose veins and deep vein thrombosis (DVT) where blood flow from the legs back to the heart may be impaired. Raynaud phenomenon is another possible cause.
Various joint problems may present with burning of the feet, mainly around the affected joint. This is seen with conditions like rheumatoid arthritis, osteoarthritis and gout. Rheumatoid arthritis is an autoimmune condition that mainly affects the small joints. Osteoathritis tends to involve the larger joints. Gout is mainly isolated to the toes and specifically the large toe. Gouty arthritis is a condition where the build up of uric acid in the joint spaces leads to inflammation of the affected joint.
Certain nutritional deficiencies can lead to a burning sensation or pain due to the effect that these deficiencies have on the nerves. This is mainly seen with folate and vitamin B12 deficiency. These deficiencies may arise when certain foods are restricted in the diet, with extreme dieting or fasting and malabsorption syndromes where these nutrients are not absorbed from the gut.
Medication and Substances
Some medication may lead to burning of the feet mainly due to affecting the nerves of the feet. This may be seen with chemotherapy (anti-cancer drugs). Cholesterol-lowering drugs like statins are also at times implicated with the aggravation of nerve-related conditions but this has not be conclusively proven. Other substances can also affect the nerves and lead to a burning sensation in the feet. In alcoholic neuropathy, the long term use of excessive amounts of alcohol may damage the nerves and lead to abnormal sensations such as burning.