After laying down for a bit and then standing up I get real dizzy. Why?

[Laura1997]

So here's a problem I've faced for the past 3 years or so.
Every time after laying down even for a little bit, then standing up I get real dizzy. It once made me pass out for just a second, making me fall to the floor. When I stand up, I have to sit down or move my head down in order to get the dizziness to go away. This happens when I wake up and when I'm just watching TV and then standing up.
Does anyone have an idea what's the cause of this and whether or not I should see a doctor?

[Red_Star]

You have what is called orthostatic hypotension (also called postural hypotension). This is a form of low blood pressure that happens when you stand up from sitting or lying down. You can feel dizzy, llightheaded or even faint. I had orthostatic hypotension myself when I had untreated hypothyroidism. As your symptom has been ongoing for a few years you might want to see a doctor.

Excerpt from American Family Physician - Evaluation and Management of Orthostatic Hypotension...

"Differential Diagnosis of Orthostatic Hypotension

Cardiovascular:
Anemia
Cardiac arrhythmia
Congestive heart failure
Myocardial infarction
Myocarditis
Pericarditis
Valvular heart disease
Venous insufficiency

Drugs:
Alcohol
Antiadrenergics
Antianginals
Antiarrhythmics
Anticholinergics
Antidepressants
Antihypertensives
Antiparkinsonian agents
Diuretics
Narcotics
Neuroleptics
Sedatives

Endocrine:
Adrenal insufficiency
Diabetes insipidus
Hyperglycemia, acute
Hypoaldosteronism
Hypokalemia
Hypothyroidism
Pheochromocytoma

Intravascular volume depletion:
Blood loss
Dehydration
Pregnancy/postpartum
Shock

Miscellaneous:
AIDS
Anxiety or panic disorder
Eating disorders
Prolonged bed rest"