Two kinds of skin allergies, or dermatitis, are caused by substances coming in contact with the skin: primary irritant dermatitis and allergic contact dermatitis. Primary irritant dermatitis is a non-allergic reaction of the skin resulting from exposure to an irritating substance. Allergic contact dermatitis is an allergic sensitization to various substances.
People who work in areas where their feet are exposed to repeated or prolonged contact to hot water, chemicals, oils, or wet cement can develop primary irritant dermatitis. Some solutions are safe if used properly. However, improper use can lead to a serious contact dermatitis. This is particularly dangerous for diabetics. For primary irritant dermatitis, soaking feet in solutions, such as bleach, vinegar, salt water, or Betadine, can be beneficial as long as excessive amounts are not used.
Allergic contact dermatitis is the result of exposure to substances that sensitize the skin. Each time the foot is exposed to the substance, an inflammatory reaction occurs. Some people are allergic to the substances in sock dyes or certain shoe materials. Adhesive tapes can cause an allergic reaction with blisters or a rash developing beneath the tape. Because of the heat and the accumulation of moisture beneath the tape, an acute Athlete's Foot infection can also be caused by an allergic reaction to the adhesive. Treatments include the use of cool compresses, topical steroid compounds (like hydrocortisone creams), and antifungal creams.
Athlete's Foot (tenia pedis)
Athlete's Foot, also known as tinea pedis, is a skin disease caused by a fungus that usually occurs between the toes. The fungus attacks the feet because shoes create a warm, dark, and humid environment that encourages fungus growth. Warm, damp areas around swimming pools, showers, and locker rooms are also breeding grounds for fungi.
Symptoms of Athlete's Foot include drying skin, itching, scaling, inflammation, and blisters on and between the toes. Athlete's Foot can spread to the soles of the feet and to the toenails as well as other parts of the body, which is why timely treatment is so important.
You can prevent Athlete's Foot by:
- Not walking barefoot, particularly in public pools and locker rooms.
- Reducing foot perspiration by using talcum powder.
- Wearing light and airy shoes.
- Wearing socks that keep your feet dry, and changing them frequently if you perspire heavily.
While fungicidal and fungistatic chemicals are usually used to treat Athlete's Foot problems, they often fail to contact the fungi in the lower layers of the skin. For persistent Athlete's Foot, a prescription topical or oral antifungal drug may be needed. Note: Please consult your physician before taking any medications.
Most blisters on the feet are caused by friction and do not require medical attention. New skin will form underneath the affected area and the fluid built up in the blister is simply absorbed back into the tissue. You can soothe ordinary blisters with vitamin E ointment or an aloe-based cream.
Do not puncture a blister unless it is large, painful, or likely to be further irritated. If you have to pop a blister, use a sterilized needle or razor blade. Wash the area thoroughly, then make a small hole and gently squeeze out the clear fluid. Apply a dab of hydrogen peroxide to help protect against infection. Do not remove the skin over a broken blister. The new skin underneath needs this protective cover. Cover the area with a bandage and mild compression.
If the fluid is white or yellow, the blister is infected and needs medical attention.
You can prevent blisters by breaking in new shoes gradually, and putting petroleum jelly or an adhesive bandage on areas that take the rub—before the blister happens. Wear socks that have heels instead of tube socks (they bunch up and cause blisters). Acrylic and other synthetic-fiber socks are good choices. Be sure to wash and dry your feet daily to prevent bacterial infections, such as Athlete's Foot.
Burning feet refers to a foot sensation that is most frequently experienced by adults over age 50 and those who are diabetic. Thyroid dysfunction, gastric restriction in morbidly obese people, and heavy use of alcohol also have been linked with burning feet. Nerve problems, such as neuromas and tarsal tunnel syndrome, may also be associated with the sensation of burning feet.
It is not unusual for feet to ache or burn at the end of a long day. However, on an ongoing basis, burning feet can be a symptom of a more serious health problem. Please consult our office and schedule an appointment if you experience persistent burning feet.
There are some simple ways to mitigate burning feet:
- Make sure you wear shoes that fit properly and provide support for your unique foot structure.
- Take foot baths daily to treat hot and sweaty feet.
- Wear socks of cotton, versus synthetic, fibers as they are lighter and cooler.
- Avoid long periods of standing.
- Try cushioned or shock-absorbing insoles in your shoes to make standing more comfortable.
- In some cases, orthotics may be helpful to correct any underlying mechanical imbalances which may be responsible for your burning feet.
A callus, also known as hyperkeratosis, is an area of hard, thickened skin that can occur across the ball of the foot, on the heel, or on the outer side of the big toe. Although many consider them a skin problem, they are indicative of a problem with the bone.
Calluses form from repeated friction and pressure, as the shoe (or ground) rubs against a bony prominence (bone spur) on the toe or foot. The skin thickens in response to this pressure. Small amounts of friction or pressure over long periods of time cause a corn or callus. A great deal of friction or pressure over shorter periods of time can cause blisters or open sores. Calluses typically develop under a metatarsal head (the long bone that forms the ball of the foot). Calluses have painful nerves and bursal sacs (fluid-filled balloons that act as shock absorbers) beneath them, causing symptoms ranging from sharp, shooting pain to dull, aching soreness.
Calluses can be treated with over-the-counter callus removers, which use strong acids to peel this excess skin away after repeated application. Be careful using these products as they can cause chemical burns when misapplied or used in excess. Alternatively, treat calluses as follows: Begin by soaking the foot or feet in warm soapy water and gently rubbing away any dead skin that loosens. Next, use a pumice stone or emery board to file away the thickened skin. Apply a good moisturizer to the hardened areas to keep them softer and relieve pain. Nonmedicated corn pads or moleskin (a thin fuzzy sheet of fabric with an adhesive back) are available in stores and can relieve pain caused by calluses. However, use caution removing pads or moleskins to avoid tearing the skin.
If you need assistance relieving calluses, please contact our office. We can trim and apply comfortable padding to the painful areas. In more severe cases, we may prescribe medication to relieve inflammation, or inject cortisone into the underlying bursal sac to rapidly reduce pain and swelling.
A plantar callus forms on the bottom of the heel over time where one metatarsal bone is longer or lower than the others. This structure causes the one metatarsal to hit the ground first and with more force than it is equipped to handle. As a result, the skin under this bone thickens. In most cases, plantar calluses can be treated without surgery. In some recurring cases, however, a surgical procedure, called an osteotomy, is performed to relieve the pressure on the bone.
A condition called Intractable Plantar Keratosis (IPK) is a deep callus directly under the ball of the foot. IPK is caused by a "dropped metatarsal," which happens when the metatarsal head drops to a lower level than the surrounding metatarsals and protrudes from the bottom of the foot. This results in more pressure being applied in this area and causes a thick callus to form. A dropped metatarsal can either be a congenital abnormality, a result of a metatarsal fracture, or a structural change that may have occurred over time.
You can prevent calluses by:
- Switching to better-fitting shoes or using an orthotic device to correct an underlying cause.
- Buying socks with double-thick toes and heels or nylon hose with woven cotton soles on the bottom of the foot.
Corns are calluses that form on the toes because of bones that push up against shoes and build up pressure on the skin. The surface layer of the skin thickens, irritating the tissues underneath. Hard corns are usually located on the top of the toe or on the side of the small toe. Soft corns resemble open sores and develop between the toes as they rub against each other.
Improperly fitting shoes are a leading cause of corns. Toe deformities, such as hammertoe or claw toe, also can lead to corns. Self-care for corns includes soaking feet regularly and using a pumice stone or callus file to reduce the size of the corn. Special over-the-counter, non-medicated, donut-shaped foam pads can be worn to help relieve the pressure and discomfort. For large or lasting corns, please contact our office. We can shave off the corns using a scalpel.
Cysts are fluid-filled masses under the skin. Common cysts of the feet include synovial cysts, ganglia, and cutaneous mucoid cysts.
Most foot cysts are located under the skin, although occasionally they appear in tendon or bone. Synovial or ganglionic cysts are connected to a nearby joint or tendon, which makes them harder to treat. Mucoid cysts are not connected to a joint. Most cysts lead to mild pain as a result of the pressure created by wearing shoes. When any of these cysts enclose or press on a nerve, they can cause a sharp pain. X-rays, ultrasound, MRI, or CT scans are common methods for diagnosing cysts in the feet.
The best way to prevent cysts from forming is to wear well-fitted, comfortable shoes and avoid repeated foot injuries. Persistent ganglion cysts can be treated by numbing the area and extracting the fluid inside. A steroid or hardening agent may then be injected into the cyst to try to prevent it from filling again.
Extreme exposure of your feet to cold for a prolonged period can lead to a serious condition called frostbite. Frostbite starts by producing pain and a burning sensation in the exposed areas. This is followed by numbness in toes or feet and changes in skin color, from pale or red to bluish-gray or black. People with a history of frostbite often get it again in the same place.
Superficial frostbite injuries refer to those that involve the skin and subcutaneous tissue. When the damage goes more deeply, beyond the subcutaneous tissue and into muscles, nerves, tendons, or bones, they are classified as deep frostbite injuries. The extent of the injury impacts the prognosis for healing and long-term complications.
Children, the elderly, and diabetics are more prone to frostbite because of the size of their extremities or poor circulation. People who live or work outdoors also have a higher likelihood of contracting frostbite because of their increased exposure to the cold.
If you suspect that you have frostbite, seek emergency medical care as soon as possible. Get out of the cold and into a warm environment as quickly as possible. Keep the feet dry and warm. Do not expose the flesh to extremely warm or hot temperatures (such as a fire or portable heater). A gradual and steady warming procedure should be followed.
Gangrene is caused by lost blood supply to the foot or bacterial infections that result from open sores or ulcers. Diabetics are most prone to foot gangrene because they typically have poor circulation or nerve damage, which can lead to loss of blood supply.
Any sudden onset of foot or leg pain accompanied by lower skin temperature and skin color changes may indicate a sudden blockage of blood flow to the legs.
Gangrene is a serious condition, particularly when it is caused by an infection, which can spread throughout the body. Gangrenous tissue must be surgically removed, followed by oxygen treatment and intravenous antibiotics to kill any infection. If you suspect gangrene, please contact our office or seek other immediate medical attention.
Skin lesions refer to any variation in skin color or texture anywhere on the body. Some skin lesions are present at birth, such as moles, freckles, or birthmarks. Others are acquired over time, such as acne, warts, allergies, sunburn, or abrasions. Most skin lesions are harmless. However, it is important to keep an eye on them because they can change over time, which may be indicative of a serious problem. For example, one pigmented lesion that can occur on the foot and lower extremity is malignant melanoma.
A condition called actinic keratosis is another cancer-causing lesion that can occur on the feet. It is most commonly found in sun-exposed areas, such as the top of the foot. Treatment consists of freezing the lesions with liquid nitrogen or sharp excision.
Kaposi's Sarcoma is another cancerous lesion that may appear on the soles of the feet of people with HIV infection or AIDS. Kaposi's Sarcoma lesions are irregular in shape and have a purplish, reddish, or bluish-black appearance. They tend to spread and form large plaques or become nodular. The nodular lesions have a firm, rubbery appearance.
Psoriasis is a common, chronic, and recurrent inflammatory disease of the skin characterized by round, reddish, dry scaley patches covered by grayish-white or silvery-white scales. Lesions are most commonly found on the nails, scalp, elbows, shins and feet. In the foot, psoriasis can be difficult to distinguish from Athlete's Foot, or the nail appearance may be confused with fungal infections of the toenails.
Psoriasis can cause a characteristic pitting appearance on the nails. Pustular psoriasis is a form of the disease characterized by small pustules or blisters filled with clear or cloudy fluid.
Psoriasis can affect the joints of the feet and lower extremities, leading to painful arthritis. Anti-inflammatory medications, steroids, and other medications are common treatment for psoriasis. Note: Please consult your physician before taking any medications.
Smelly Feet and Foot Odor
The feet and hands contain more sweat glands than any other part of the body, with roughly 3,000 glands per square inch. Smelly feet are not only embarrassing, but can be physically uncomfortable as well.
Feet smell for two reasons: 1) shoe wear, and 2) sweating of the feet. The interaction between the perspiration and the bacteria that thrive in shoes and socks generates the odor. Therefore, any attempt to reduce foot odor has to address both sweating and footwear.
Smelly feet or excessive sweating can also be caused by an inherited condition, called hyperhidrosis, which primarily affects men. Stress, some medications, fluid intake, and hormonal changes also can increase the amount of perspiration our bodies produce.
In general, smelly feet can be controlled with a few preventive measures:
- Always wear socks with closed shoes.
- Avoid wearing nylon socks or plastic shoes. Instead, wear shoes made of leather, canvas, mesh, or other materials that let your feet breathe.
- Bathe feet daily in lukewarm water, using a mild soap. Dry thoroughly.
- Change socks and shoes at least once a day.
- Check for fungal infections between toes and on the bottoms of your feet. If any redness or dry, patchy skin is observed, get treatment right away.
- Don't wear the same pair of shoes two days in a row. If you frequently wear athletic shoes, alternate pairs so that the shoes can dry out. Give your shoes at least 24 hours to air out between wearings; if the odor doesn't go away, discard the shoes.
- Dust your feet frequently with a nonmedicated baby powder or foot powder. Applying antibacterial ointment also may help.
- Practice good foot hygiene to keep bacteria levels at a minimum.
- Wear thick, soft socks to help draw moisture away from the feet. Cotton and other absorbent materials are best.
Treating Foot Odor
The best home remedy for foot odor is to soak feet in strong black tea for 30 minutes a day for a week. The acid in the tea kills the bacteria and closes the pores, keeping your feet dry longer. Use two tea bags per pint of water. Boil for 15 minutes, then add two quarts of cool water. Soak your feet in the cool solution. Alternately, you can soak your feet in a solution of one part vinegar and two parts water.
Persistent foot odor can indicate a low-grade infection or a severe case of hereditary sweating. In these cases, a prescription ointment may be required to treat the problem.
Treating Excessive Sweating
A form of electrolysis, called iontophoresis, has been shown to reduce excessive sweating of the feet. However, it is more difficult to administer. In the worst cases of hyperhidrosis, a surgeon can cut the nerve that controls sweating. Recent advances in technology have made this surgery much safer, but may increase sweating in other areas of the body.
Swelling of the feet, ankles and legs, also known as edema, is often caused by an abnormal build-up of fluids in ankle and leg tissues. Painless swelling of the feet and ankles is a common problem, particularly in older people. It may affect both legs, including the calves and/or thighs. Because of gravity, swelling is particularly noticeable in the lower legs. Swelling in the legs and feet may also be a symptom of other, more serious health issues, such as heart failure, renal failure, or liver failure.
Common causes of foot, ankle, and leg edema include:
- Blood pressure-lowering drugs.
- Body fluid overload.
- Certain antidepressants.
- Congestive heart failure.
- Diagnostic tests.
- Estrogens and progestin oral contraceptives.
- Extremity surgery.
- Generalized allergy.
- Glomerulonephritis or other kinds of kidney disorders.
- Infiltration of an intravenous site.
- Injury or trauma to the ankle or foot.
- Insect bite or sting.
- Long airplane flights or automobile rides.
- Long-term corticosteroid therapy.
- Medical treatments.
- Menstrual periods (for some women).
- Pregnancy (mild to severe swelling).
- Prolonged standing.
- Starvation or malnutrition.
- Venous insufficiency (varicose veins).
You can mitigate swelling by elevating your legs above the heart while lying down. Avoid sitting or standing without moving for prolonged periods of time. Avoid putting anything directly under the knees when lying down, and don't wear constricting clothing or garters on the upper legs.
Exercising the legs causes the fluid to work back into the veins and lymphatic channels so that the swelling goes down. Mild pressure applied by elastic bandages or support stockings can help reduce ankle swelling. A low-salt diet may also help reduce fluid retention and decrease the ankle swelling.
Ulcers are skin wounds that are slow to heal. In the foot, as prominent metatarsal heads on the plantar (bottom of the foot)are subjected to increased pressure, the skin begins to become callused. When subjected to shearing forces, there is a separation between the layers on this callused skin, which fills with fluid and becomes contaminated and infected. The result is a foot ulcer.
Ulcers are classified in four stages, according to how deeply they penetrate the layers of skin they have broken through.
The four stages of ulcers are:
- Stage 1—Characterized by reddening wounds over bony areas. The redness on the skin does not go away when pressure is relieved.
- Stage 2—Characterized by blisters, peeling, or cracked skin. There is a partial thickness skin loss involving the top two layers of the skin.
- Stage 3—Characterized by broken skin and sometimes bloody drainage. There is a full thickness skin loss involving subcutaneous tissue (the tissue between the skin and the muscle.)
- Stage 4—Characterized by breaks in the skin involving skin, muscle, tendon, and bone and are often associated with a bone infection (osteomyelitis).
The are also four major cause of foot ulcers:
- Neuropathic—Related to the nerves and characterized by a loss of sensation in the feet.
- Arterial—Related to poor blood circulation to the lower extremity. This type of ulcer can be very painful and is usually found on the tips of toes, lower legs, ankle, heel, and top of the foot. It can very easily become infected.
- Venous—Related to compromised veins. These ulcers are often seen around the inside of the ankle and are slow to heal.
- Decubitus—Derived from excessive and prolonged pressure on one area of the foot. The most common type of decubitus ulcer of the feet is bed sores on the backs of the heels of people confined to bed for long periods of time.
Foot ulcers are a common problem for diabetics. Contact casts are sometimes applied to the diabetic foot to relieve the bony prominent areas of pressure, allowing ulcers to heal.
Most foot warts are harmless, even though they may be painful. They are often mistaken for corns or calluses, which are layers of dead skin that build up to protect an area which is being continuously irritated. A wart, however, is caused by a viral infection which invades the skin through small or invisible cuts and abrasions. Foot warts are generally raised and fleshy and can appear anywhere on the foot or toes. Occasionally, warts can spontaneously disappear after a short time, and then, just as frequently, they recur in the same location. If left untreated, warts can grow to an inch or more in circumference and can spread into clusters of warts. Children, especially teenagers, tend to be more susceptible to warts than adults.
Plantar warts, also known as verrucas, appear on the soles of the feet and are one of several soft tissue conditions that can be quite painful. Unlike other foot warts, plantar warts tend to be hard and flat, with a rough surface and well-defined boundaries. They are often gray or brown (but the color may vary), with a center that appears as one or more pinpoints of black. Plantar warts are often contracted by walking barefoot on dirty surfaces or littered ground. The virus that causes plantar warts thrives in warm, moist environments, making infection a common occurrence in public pools and locker rooms.
Like any other infectious lesion, plantar warts are spread by touching, scratching, or even by contact with skin shed from another wart. The wart may also bleed, another route for spreading. Plantar warts that develop on the weight-bearing areas of the foot (the ball or heel of the foot) can cause a sharp, burning pain. Pain occurs when weight is brought to bear directly on the wart, although pressure on the side of a wart can create equally intense pain.
To prevent the spread of warts, follow these tips:
- Avoid direct contact with warts, both from other persons or from other parts of the body.
- Avoid walking barefoot, except on sandy beaches.
- Change your shoes and socks daily.
- Check your children's feet periodically.
- Keep your feet clean and dry.
It is important to note that warts can be very resistant to treatment and have a tendency to reoccur. Over-the-counter foot wart treatments are usually ineffective because their use can inadvertently destroy surrounding healthy tissue. Please contact our office for help in effectively treating warts. Our practice is expert in recommending the best treatment for each patient, ranging from prescription ointments or medications to, in the most severe cases, laser cautery.