The evaluation of fainting begins with a medical history and physical examination.

Physical findings in someone with an episode of fainting may include:

• Rapid pulse
• Irregular pulse
• Excessive sweating
• Heart murmur
• High blood pressure
• Low blood pressure
• Leg swelling (bilateral)
• Swelling of the veins in the neck
• Xanthelasma:
• Fatty deposits in the skin.

Testing may be required in order to investigate the underlying cause for fainting in adults over the age of 40, or those who have risk factors for stroke or heart disease.

Tests that may be used to evaluate fainting include:

• Serum pregnancy test
• Blood glucose testing
• Pulse oximetry
• Electrolyte profile
• Kidney profile
• Complete blood count
• Cardiac enzymes
• Thyroid profile
• Chest x-ray
• Electrocardiogram
• Cardiac monitoring
• 24-hour cardiac monitor:
• A portable ECG that measures the heart's rate and rhythm over a 24-hour period (or longer)
• Echocardiogram
• EEG

Less commonly performed tests that may be used to evaluate fainting include:

• CT scanning of the brain
• MRI scan of the brain
• Carotid angiogram:
• A special x-ray procedure that can detect blood vessel narrowing in the carotid arteries, which often cause strokes.
• Carotid duplex ultrasound, or doppler ultrasound: can detect narrowing and reduced blood flow in the carotid arteries that supply the brain
• Exercise stress test
• Cardiac catheterization
• Thallium heart scan