Itchy Feet

Tinea, eczema, hives, chilblains and bug bites are common causes of itchy feet, it can also be a symptom of more serious disease such as liver and kidney dysfunction or disorders which affect the nerves in the feet. Identifying the cause of itchy feet is important to be able to provide appropriate treatment for relief. Itching is known as pruritis. 

Common causes of Itchy Feet

Tinea of the feet is known as Athletics foot (tinea pedis). It is a common, highly contagious fungal infection which thrives in the warm, moist environments of the feet, especially between toes, causing the skin to peel, crack and itch. 

Psoriasis is an autoimmune disease that causes dry skin plaques and pustules. It can affect any part of the skin, including the soles of the feet and nails.  

Eczema/Atopic dermatitis (AD) 
is a chronic condition which causes the skin to become dry, inflamed and itch. AD develops due an inappropriate allergic response and can affect any part of the body. Itching can be due to the release of histamine by mast cells in the skin which occurs when the skin is damaged, inflamed or under attack. Once histamine has been released it can excite the sensory nerve endings near the surface of the skin. 

Hives/Contact dermatitis can cause an intensely itching rash and is due to the skin coming into direct contact to a substance causing a reaction. An itchy rash, along with other symptoms such as swelling, burning and tenderness, bumps and blisters which may ooze, can occur. Any number of substances can result in contact dermatitis or an allergic response which can occur after just one exposure or after repeated exposures. In the case of itchy feet, it may be due to changes in washing powder, soap or any surface bare feet have come into contact with [9].

Chilblains are patches of red, swollen and itchy skin that usually occur on the toes, fingers, nose and earlobes, thought due to sensitivity to temperature changes and poor circulation. The small blood vessels in the toes can constrict and restrict blood flow. As the skin re-warms fluid can leak from blood vessels into surrounding tissues resulting in swelling and redness of the skin in chilblains.

Scabies (Ectoparasites) are tiny mites which feed of skin. The female scabies mite burrows into the skin to lay her eggs.

When these eggs hatch, they travel to the skin surface, mate, travel back down a hair follicle and lay their eggs - causing a perpetual cycle of infestation. It is the burrowing that causes skin irritation and intense itching. They are transmitted by direct human contact or from bedding.

Pharmaceutical treatments are available to eradicate infestation. Regular vacuuming of bedding and changing sheeting can help prevent transmission.

Diseases causing Itchy Feet

Many symptoms can be associated with serious health disorders and medical advice should be sought for any symptoms which cannot be explained. Itchy feet can be associated with liver and kidney disease and many neurological disorders (diseases of the nervous system). 

Liver disease. A dysfunctional liver can result in a build-up of bilirubin. Bilirubin is a yellow substance formed from the breakdown of red blood cells and is usually removed by the liver. Yellowing and itching skin is a symptom of high levels of bilirubin. 

Kidney disease. The kidneys normally filter substances from the blood. When they are not functioning properly these substances can build-up causing severe itching (uremic pruritus), particularly the soles of the feet and palms of the hands [11].

Nervous system disorders. Dysfunction of the itch-sensing neurons due to neurological disease. These are the same diseases which cause neuropathic pain, however instead of pain (or as well as) an intense itching sensation is felt. The intense itch leads to a desire to scratch which only offers limited relief. Neuropathic itch is hard to resolve.

Neurological diseases which may cause itching feet include shingles, diabetes and pre-diabetes, (small-fibre polyneuropathies), pinched nerves (radiculopathies), and disorders of the central nervous system such as strokes or multiple sclerosis (MS).

• Shingles is a viral infection caused by the varicella zoster virus, only occurring after someone has been infected with chicken pox in the past. This disease causes a rash of painful blisters. In some cases the pain, or itch can last for weeks, months or years and is known as post-neuralgic pain (2).
• Small-fibre polyneuropathies – these are associated with diabetes and impaired glucose metabolism (pre diabetes). Often starting in the feet, they may involve symptoms of tingling, burning, numbness and pins-and-needles type sensations [3].
• Radiculopathies - pinching of a nerve root in the spinal column.
• Disorders of the central nervous system can result in lesions affecting sensory pathways [1].

Itchy feet due to serious medical conditions need to be under the care of a medical professional. 

Natural treatment suggestions for Itchy Feet 

The following suggestions may help with itchy feet from common causes. Applying natural topical skincare can help reduce irritation, infection, and promote healing.

Tea tree (Melaleuca alternifolia) oil offers antiseptic, antibacterial, antifungal and anti-inflammatory properties. Tea tree oil is found in many skincare products for tinea and has demonstrated benefit in reducing itching, along with an antimicrobial and anti-inflammatory action, making tea tree a useful treatment of fungal infections [7].

German camomile (Matricaria recutita L.) offers anti-inflammatory, antibacterial and antifungal activity, and can support wound healing.

Colloidal oatmeal (Avena sativa) offers skin protection, antipruritic (stops the itch), and an anti-inflammatory action. 

Aloe vera (Aloe barbadensis) gel provides anti-inflammatory, anti-pruritic and antibacterial action, and offers healing properties.

Small Stinging-nettle (Urtica dioica)is beneficial for itchy, red and irritated skin.

St. John’s wort (Hypericum perforatum) and Licorice (Glycyrrhiza glabra) have been shown to be effective in the treatment of atopic dermatitis [8].

Supporting circulation

Ginger (Zingiber officinale) enhances circulation and reduces inflammation.

Chilli contains a substance called capsaicin which enhances circulation to the peripheries (feet) and can reduce inflammation by blocking the effects of substance P in the body. Substance P's most well-known function is as a neurotransmitter and a modulator of pain perception - by altering cellular signaling pathways. Substance P has been shown to play a role in itch signalling, and is suggested as a rational target for addressing chronic itching [10].  Capsaicin or chilli cream should not be applied to open wounds. 

Preventative measures for Itchy Feet 

Microbial dysbiosis is implicated in the development of tinea – this is an imbalance of fungal and bacteria environment of the skin. Research has shown the composition of bacteria and fungus of patients with tinea is different from that of a non-fungal person’s foot, and different forms of tinea may differ in the composition of microbiota [2]. Probiotics supplements which target skin health include:

• Lactobacillus rhamnosus (LGG®)
• Bifidobacterium animalis ssp lactis (BB-12®)

Tinea grows in a moist environment and is highly contagious. Preventive measures include:

• Drying feet well after showering, especially between toes
• Wearing shoes such as thongs in public showers to avoid contamination
• Avoid sharing towels or footwear

The right foot wear is important

The shoes you wear, depending on the particular season, can be a risk factor for the development of tinea. This is due to the humidity and temperature created within shoes which may present an ideal environment for the growth of fungi and bacteria [5].

Factors to consider:

• Closed shoes create a higher temperature and humidity level increasing the risk of infection
• Cloth material creates the highest level of temperature and humidity, followed closely by shoes made of synthetic or artificial leather, natural leather, athletic and mesh
• Slippers and sandals offered the least risk of developing tinea pedis
• Consider changing shoes type if at risk
• Maintain footwear
• Wear moisture-absorbent socks
• Apply a foot powder to help absorb moisture on feet and in shoes

The information provided is not intended to be used for diagnosis or treatment. If you are experiencing any health concerns please consult your doctor for advice.

References

1. Neuropathic Itch - PMC (nih.gov)
2. Shingles | Australian Government Department of Health and Aged Care
3. Small Fiber Sensory Neuropathy (hopkinsmedicine.org)
4. Characterization of Skin Microbiome in Tinea Pedis  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6842383/
5. Internal environment of footwear is a risk factor for tinea pedis https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6900014/
6. https://www.msdmanuals.com/professional/SearchResults?query=tinea+pedis
7. Melaleuca alternifolia (Tea Tree) Oil: a Review of Antimicrobial and Other Medicinal Properties https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1360273/
8. Which plant for which skin disease? Part 1: Atopic dermatitis, psoriasis, acne, condyloma and herpes simplex https://pubmed.ncbi.nlm.nih.gov/20707875/
9. https://www.mayoclinic.org/diseases-conditions/contact-dermatitis/symptoms-causes/syc-20352742
10. Substance P and neurokinin 1 receptor are new targets for the treatment of chronic pruritus https://pubmed.ncbi.nlm.nih.gov/31016733/
11. Pruritus in Kidney Disease https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5497472/