Can you go into a coma from low blood pressure?

Yes, but uncommon.: If BP is too low, one can faint (loss of consciousness) until ones head is level with ones feet (usually, if one falls due to fainting, consciousness returns soon after one falls to the ground). Unconsciousness when one faints is, in some sense, a transient comatose state. If low BP causes fainting, upon awakening, if one does not drink or get IV fluids, fainting can recur upon sitting up.