Can low BP cause lightheadedness and nausea in an elderly patient with diabetes?
Sorry to learn about your bothersome symptoms.
You should check your glucose at the time of symptoms to ensure it was not a low blood glucose reaction ('hypoglycemia'). However hypoglycemia typically occurs only if you are on certain types of oral medications or insulin for diabetes.
It would be ideal to even check blood pressure at the time of symptoms. If indeed low, then a reduction in the doses of blood pressure lowering medication will need to be discussed with your doctor. Sometimes the number of pills taken for treatment of high blood pressure can be reduced too.
But generally it is best to avail of 911 services when a potential emergency occurs.
Once stable and out of immediate danger, consult a doctor to determine the actual cause of these symptoms.
When I see someone like you in my practice, I typically order the following blood tests in addition to a detailed physical examination:
CBC (Complete Blood Count, also known as Hemogram; includes Hemoglobin, WBC and Platelet counts)
Electrolytes (Sodium and Potassium in particular)
HbA1c (Glycosylated Hemoglobin = your last 3 months' glucose average). Also known by other names such as GlycoHemoglobin or Glycated Hemoglobin or A1c
Liver function tests (SGOT , SGPT, Albumin, Bilirubin, Alkaline Phosphatase)
Kidney function tests (BUN, Creatinine)
TSH (checks your thyroid) 12 hour Fasting Lipid profile
Urine albumin to Creatinine Ratio (early sign of diabetes affecting the kidney)
25 hydroxy Vitamin D levels (ideal range 40 to 60 ng/ml = 100 to 150 nmol/liter)
Correct diagnosis and treatment requires the opportunity to examine the patient so you must see an endocrinologist in-person.