Hello As you mentioned that you feel faintness sometimes when stand up , so this may be due to following reasons, these includes. 1 Orthostatic hypo tension as this is a most common cause of dizziness or faintness in a female or male of 42 years . Diagnosis can be confirmed by physical examination at the time of this type of attack. 2 Anemia may be the another reason of such faintness , diagnosis can be confirmed by hemoglobin examination . 3 Hypertension is another most common cause in patients ( particularly family history). Again physical examination will find out the exact reason of such cases. There are so many other reason of such faintness as tumor in brain , Miener s disease , Hypoglycemia. But consult a physician and get his opinion.