Numbness, pain and tingling in the foot may be caused by a variety of conditions, including nerve damage, herniated disk or lack of blood supply to the affected area, or from sitting or standing for too long, according to MedlinePlus. Animal, spider or other insect bites are also possible causes.
Serious medical conditions may cause numbness or tingling sensations, which often affect feet, legs, arms and hands, explains MedlinePlus. Diabetes, multiple sclerosis, stroke, seizures and underactive thyroid are all potential causes. Additionally, the sensation may be brought on by vitamin deficiencies or unusual levels of potassium, sodium or calcium. Numbness and tingling may be side effects from the use of some medications or can be the result of alcohol, tobacco, chemotherapy drugs or radiation therapy.
Diagnosing and treating the underlying condition may relieve or cure the sensation, according to MedlinePlus. A patient feeling unexplained numbness, pain or tingling should contact a medical professional if he experiences paralysis or an inability to control movement of his limbs. Unusual symptoms such as dizziness, muscle spasms, unexplained rash and frequent or uncontrollable urination should be treated by a doctor. Diagnosis may include a series of imaging tests on the nervous system, including X-rays, ultrasounds, CT scans and an MRI. Blood tests may be taken to diagnose thyroid function, toxicology, vitamin and electrolyte levels and liver function.