My mom is 50 years of age, she has been feeling unusual lately, when she stands up she feels dizzy, lose of coordination, and nausea. What could it be?

See your doctor. What chronic medical conditions does your mother have? The symptoms of dizziness, loss of coordination, nausea, blurry vision, and sweating, can all indicate e low blood sugar, or low blood pressure as a result of diabetes, heart conditions, or even other medications. She should see her doctor right away to evaluate these symptoms.
Lots. See MD. Don't have details. Could be drop in blood pressure, heart rhythm disturbance, inner ear problem (infection, tumor), stroke, brain tumor, less likely adrenal problem; could be from anemia due to a number of causes. Needs to be seen and evaluated. Bedside neurol tests, blood tests, perhaps additional studies or referral to ent, or neurologist, or cardiologist, etc. See md soon. If acute, er now.