What Causes Sudden Loss Of Consciousness?
Two main possibilities.
Detailed Answer:
I read your question carefully and I understand your concern.
One main possibility would be that of a drop in blood pressure with insufficient blood supply to the brain. Low blood pressure in itself can have different origins. The main one to investigate would be that of a heart arrhythmia which may cause insufficient blood pumping to the brain. If episodes happened when changing position from supine to standing orthostatic hypotension would be another possibility.
The other main possibility to be considered would be that of a seizure. Seizures can come in different forms, not necessarily with convulsions, an atonic seizure with immediate loss of muscle tone and loss of consciousness may manifest this way.
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