Dark Spot Under My Skin on Bottom of Foot

Dark spots under the skin on the bottom of your foot might appear harmless, but in some cases the spots are symptoms of internal bleeding and might require emergency treatment, according to MayoClinic.com. Recognize the likely cause of dark spots under your foot to ensure your well-being.

Significance

MedlinePlus reports that dark spots underneath the skin on the bottom of your foot can be signs of a blood-clotting disorder called purpura. Purpura spots, which can be red or purple, are commonly confused with birthmarks, although purpura are temporary and birthmarks are permanent. The condition makes you more prone to bleeding or bruises and affects both children and adults. Women are more prone to the condition than men, while adults older than age 60 also face a high risk for purpura.

Function

Low levels of platelets, which are cells responsible for helping your blood clot, are the trigger of purpura, although the exact cause of the condition remains a mystery. Most people with purpura experience an immune system breakdown that results in an unhealthful reduction of platelets. While a normal adult or child may have up to 450,000 platelets, someone with purpura often has less than 20,000 and is vulnerable to internal bleeding, reports MayoClinic.com.

Effects

Dark spots are often the only symptom of purpura, although you may have the condition if you bruise or bleed easily. Petechiae, a type of purpura that does not resemble birthmarks, is identified by the appearance of a rash of small red or purple spots that can also appear under the skin on your lower legs or feet, reports the Cleveland Clinic.

Potential

Children recovering from a viral infection such as the mumps or flu face the highest risk for purpura and most experience a healthy recovery within a few weeks without the need for treatment, according to the National Heart, Lung and Blood Institute. Purpura is typically chronic when diagnosed in adults. Your doctor may suggest a treatment for purpura based on your platelet count and symptoms. Purpura without signs of bleeding that accompanies a regular platelet count may relieve without treatment, while medications or surgery are required for serious cases of the condition.

Considerations

Purpura may cause bleeding in the brain in serious cases and can be fatal, according to the Cleveland Clinic. Most complications from purpura result from surgery and corticosteroids prescribed to remedy the condition. Your risk increases for cataracts, decreased muscle mass, osteoporosis and diabetes after long-term exposure to corticosteroids. Removal of your spleen often becomes necessary when corticosteroids fail to remedy purpura and makes you more vulnerable to infection.

Prevention/Solution

Avoid drugs such as aspirin or ibuprofen that can affect the function of your platelets if you have been diagnosed with purpura, according to MayoClinic.com. Reduce your risk for bleeding and other negative side effects of the condition by limiting your alcohol intake and be alert for any signs of infection and fever. Low-impact exercise like walking may be beneficial, although contact sports like football increase your risk for injury and bleeding.

Warning

Contact your doctor if you suffer abnormal bruising or bleeding or notice a rash of tiny purple or red spots underneath the skin on the bottom of your feet, as well as dark spots that resemble a birthmark. Women who experience a severe increase in menstrual bleeding may also have purpura and should seek a doctor's care as soon as possible.