Low Blood pressure but RBC is O.K.

Hi, I have been experiencing dizzy spell usually in the morning when I turn to my side while lying on the bed. My blood pressure is usually around 100/70 and sometime even lower.
Blood test was done and the result is within the norm.
May I know if a "weak" heart would cause the problem.What could be the cause?(I am a 30 yr old woman)

[Cleveland Clinic, MD]

Thank you for your question. Dizziness can be caused by a variety of different things.  Blood loss and dehydration are more serious causes.  Neurological problems are a potential source with strokes and TIA's as potential causes.  Inner ear problems such as labrinthitis (an infection of the inner ear) and Mineniers disease ( a progressive degeneration of the inner ear) as possible causes. Migraines are a possible cause of dizziness.  Medication side-effects are common causes of dizziness with many different medications causing this complaint. Autonomic dysfunction, more common in older men, can lead to dizziness. Cardiac causes of dizziness are usually due to fast or slow arrhythmias.  A diagnosis of psychogenic dizziness should be made only after all other causes have been excluded.

The work-up for dizziness is guided by the symptoms and the suspicions of the doctor.  It may include an ECG or Holter monitor test for heart rhythms, a tilt-table test may be used to exclude autonomic dysfunction, scans (MRI, CT) can be done to evaluate possible neurological causes as well as other neurologic tests that can be used.  A good medication review and basic blood work is usually a good idea.

In summary, many things may cause dizziness and a good internist should be able to work through them to find the source.