Multiple sclerosis is a chronic and progressive disease of the nervous system. MedlinePlus, an online medical encyclopedia, reports that scientists are not certain about the cause of multiple sclerosis, but hypothesize that an autoimmune reaction is the cause of the destruction of the myelin sheath that protects nerve cells. This nerve damage causes several possible symptoms.
Visual Disturbances
The damage caused by multiple sclerosis may disrupt the nerve signals between your brain and your eyes, which MedlinePlus reports may cause disturbances in vision. Merck Manuals describes these symptoms in more detail, saying vision may become blurred or dim. Some people have one eye that become weaker than the other, which can causes double vision. The stronger eye may behave in a strange manner, moving involuntarily, rapidly moving in one direction over and over, and then slowly drifting back to a normal position. This condition is called nystagmus. If vision is affected, people commonly lose the ability to look straight ahead, but maintain their peripheral vision. Additionally, the optic nerve may become inflamed, causing pain and blindness, usually in one eye.
Changes in Sensation
Multiple sclerosis may also damage the nerve signals between the brain and other parts of the body, which alters sensation. The Mayo Clinic reports this may cause changes in sensation, such as numbness or weakness in one or more limbs, and commonly affects one side of the body at a time or only the lower half of the body. A tingling sensation may also be felt in certain parts of the body. Merck Manuals adds that a person may feel an itchy or burning sensation in various parts of the body.
Weakness and Lack of Coordination
The nerve signals between the brain and muscles may be damaged in multiple sclerosis. The Mayo Clinic reports that damage in these nerves may result in weakness, tremor, an unsteady gait and lack of coordination. The muscles in the limbs or the lower body may also become weak, and easily fatigued. Merck Manuals adds that muscles may contract involuntarily, which causes painful cramps. Partial or complete paralysis is also possible.
Other Symptoms
Other symptoms of multiple sclerosis include dizziness and an "electric-shock" sensation in the head, especially with certain movements. According to Merck Manuals, if nerves that control urination and bowel movements become damaged, there may be a frequent urge to urinate, difficulty urinating, constipation and sometimes incontinence.
