R. Vender, MD, FRCPC

Faculty of Medicine, McMaster University, Hamilton, Ontario, Canada

This article will deal with the diagnosis and treatment of common eruptions on the feet. These conditions include:

Area of Foot


  • Tinea pedis
  • Dyshidrotic eczema (pompholyx)
  • Psoriasis
  • Juvenile plantar dermatosis
Web spaces
  • Tinea pedis
  • Dyshidrotic eczema
Dorsal surfaces
  • Contact dermatitis


Useful tests include:

  • KOH (Potassium hydroxide) exam of scale for fungus from skin and nail
  • Use a No. 15 blade and gently scrape scale from the edge of
    the plaques into the black transport paper, usually supplied by a diagnostic lab.
  • Bacteriology culture swab
  • Patch testing

Tinea Pedis (Skin and Nail)

  • One of the most common dermatologic conditions
  • Seen more often in men
  • Almost always involves the lateral web spaces
  • Soles involved and may spread onto the dorsal aspects, usually asymmetrically
  • Nail involvement may follow from a skin infection or vice versa
  • Cracking of the skin may create an entry site for bacterial infection producing secondary cellulitis
  • Often asymptomatic but can be itchy
  • Feet may be malodorous
  • Painful if fissured


  • KOH examination from the skin, subungual debris, or nail clippings confirms the diagnosis.
  • Culture determines specific name of fungus. Check the dry scale or roof of blister. May be negative if significant inflammation.

Clinical Subtypes

  • Web-space scaling and maceration. May have significant bacterial colonization.
  • Dry type. Scaling can involve skin creases or the whole sole that has a powdery scale (moccasin type).
  • Acute blistering. Small blisters often on instep
  • Soggy white skin changes with cracking
  • Nails can become involved and act as a reservoir for reinfection.


  • General measures, such as changes in footware to reduce heat and sweating
  • Wear cotton or absorbent socks.
  • Relapses are very common with any type of tinea infection of the feet, so intermittent maintenance using topical antifungals should be considered after clearance has been achieved.
  • Antifungal powders are only of value as prophylaxis.

Topical Therapy for Tinea Pedis

Area of Foot

Topical Therapy

Web spaces
  • Ciclopirox (Loprox®) and terbinafine cream (Lamisil®) have been shown to be particularly effective.
  • Clotrimazole has also been shown to be effective but may be slower acting.
  • Ciclopirox may have the added benefit of antibacterial action.
Dry type of infection
  • Confirm with KOH and culture first.
  • Topical therapy as above.
  • Oral antifungal therapy can be used if unresponsive to topicals. Monitor appropriate blood work.
Acute type of infection
  • Confirm with KOH and culture first.
  • Compressing the blisters will be necessary. Use tap water or 1oz household vinegar in 2 cups of water. Apply
    for 20 minutes q.i.d. to try to dry the blisters. This may take many days.
  • Topical antifungals should be applied after compressing.
  • Oral antifungals are often required. Monitor appropriate blood work.
Nail involvement
  • Early or mild fungal nail infection can be treated by ciclopirox 8% nail lacquer (Penlac®) to be applied once
    daily for 48 weeks, with nail debridement performed by a health professional.
  • Systemic therapy can be added for more advanced infection.

Oral Therapy for Tinea Pedis

Tinea pedis

  • Confirm with KOH and culture first.
  • Terbinafine 250mg daily for 2 weeks
  • Itraconazole (Sporanox®) studies suggest 400mg daily for 1 week or 100-200mg daily for 2-4weeks.
  • Studies comparing these two drugs and using itraconazole at 100mg showed terbinafine to be much more effective.
  • However, it is now known that a higher dose of itraconazole is required.
  • Monitor appropriate blood work.


  • Confirm with KOH and culture first and monitor appropriate blood work, i.e., CBC and LFTsat baseline and at 1 month.
  • Ciclopirox 8% nail lacquer is effective in the milder forms of nail infection. Mycological cures in the range of 52% can be achieved.
  • Adding ciclopirox 8% nail lacquer to terbinafine significantly increases cure rates.
  • Terbinafine is thought to be the treatment of choice at a dose of 250mg daily for 3 months. Using this drug for 1 week every month for 3 or 4 cycles is almost as effective, reducing both costs and worries about side-effects.

Dyshidrotic Eczema (Pompholyx)

  • A recurrent eruption affecting hands and feet seen mostly in young adults
  • Associated with atopy, hyperhidrosis, stress and an allergic contact dermatitis
  • Acute
  • Intensely itchy
  • Tiny blisters, which may become multilocular on soles and toes
  • Less commonly found in the web spaces
  • If pustules are present, swab for bacterial infection such as Staphylococcus.
  • Once the blisters settle there may be a dry, chronic, scaly, fissured rash.


  • Acute
    • Compress blisters with saline, tap water, or 10% aluminum acetate for 20 minutes q.i.d. Large blisters can be drained.
    • Moderate-to-high potency topical steroid creams should be used after compressing.
    • Studies show that immunomodulators, such as pimecrolimus (Elidel®) and tacrolimus (Protopic®), could be added with benefit.
    • Use oral antibiotics if there is a suspicion of bacterial infection, such as Staphylococcus or Streptococcus.
    • Oral antihistamines can help with itch (sedation).
    • In severe cases, oral prednisone (Deltasone®) for approximately 2 weeks should be utilized.
  • Chronic
    • Change to moderate-to-high potency topical steroid ointment rather than cream.
    • Using a topical corticosteroid intermittently, such as on weekends only, and using topical immunomodulators on weekdays has been reported.

Juvenile Plantar Dermatosis

    • Seen in childhood up to the age of 15
    • A tender, glazed erythema on the weight-bearing forefoot and toes

Nonscaly and sometimes fissured

  • No vesicles are observed
  • Worsened by sweating; may be caused by alternating sweating and drying as experienced by those who wear ‘sneakers’.
  • Rule out fungus by KOH exam.
  • 10% are patch test positive.


  • Minimize occlusive foot wear; change to cotton or absorptive socks.
  • Mild topical steroid ointments b.i.d.
  • Emollients such as petroleum jelly can be helpful.
  • Occlusive ointments such as zinc paste can help some.
  • Tar ointments have been reported as useful (e.g., 10% LCD in hydrophilic petrolatum).

Pustular Psoriasis of the Palms and Soles

  • Creamy yellow, sterile pustules on an erythematous base
  • The lesions are at different stages, and the pustules mature into a brown color and then become scaly
  • 30% of patients have psoriasis elsewhere
  • In children, especially infants, vesicopustules on the soles could suggest scabies.


  • Mild disease can be controlled with medium-to-potent topical steroids.
  • Long-term risk of atrophy. Some may respond to calcipotriol combined with a corticosteroid (Dovobet®).
  • Topical UVB/PUVA is useful in some patients.
  • Acitretin (Soriatane®) or methotrexate (Trexall®) for resistant disease

Contact Dermatitis

  • Although irritant dermatitis can be seen, allergic contact is a more significant problem.
  • Itchy eczematous dermatitis on the dorsal aspect of the feet raises the possibility of a contact dermatitis, especially to footwear.
  • The rash may be well defined at the area of contact, e.g., shoe tongue. The condition worsens with conditions that increase sweating, and in the summer months.


  • Identify and avoid the allergen.
  • Patch testing is a must if there is clinical suspicion.
  • Topical corticosteroids are the treatment of choice, but will not clear the condition if the allergen contact is still present.