Spots on the feet can be unsightly and irritating, especially if they are inflamed or sensitive to the touch. They can develop on the underside of the feet due to several medical conditions and illnesses—some that must be treated by a doctor. Therefore, it is important to understand exactly what causes spots to occur on the feet and how they can be remedied.
Spots that occur on the bottom of the feet can be brown, black, tan, pink or red in appearance. In addition, they can develop as raised, grainy bumps that are rough feeling. They can be accompanied by a variety of symptoms including itching, a fever, swelling of the lymph nodes, achy muscles and sore throat. Besides the soles of the feet, spots can appear on other places of the body such as the hands, trunk, face, arms and legs.
Moles, which can appear anywhere on the body--including the soles of the feet--occur when skin cells grow in clusters. Skin growths called plantar warts, which can also cause spots on the feet, are caused by the human papillomavirus. Sores on the feet can also be due to a bacterial infection called syphilis. In addition, stepping on objects, such as a pencil, can cause punctures on the bottom of the foot where a foreign body enters and discolors the skin.
Minor spots caused by puncture wounds can be remedied with a gentle scrubbing or by extracting the foreign object with tweezers. A doctor can remove problematic spots on the bottom of the feet surgically or through cryotherapy, a process in which the spot is frozen off with liquid nitrogen. He can also use canthardin to cause the spots to blister and pull away from the skin. Spots caused by syphilis must be treated with an injection of penicillin, which ceases the disease.
Some conditions that cause spots on the feet, such as syphilis and the human papillomavirus, can easily spread to others with contact. Always wash your hands, especially after touching any spots on your feet, and use protection if sexually active. Left untreated, spots caused by syphilis can be accompanied by more serious complications such as dementia, stroke, aneurysms, heart valve damage or meningitis.