Please help. In the episode where the patient's blood pressure dropped when he was active, what was the final diagnosis? (Friend is experiencing this and hospital has given up and telling her she'll just have to deal with it)

I would STRONGLY suggest not using the tv show to diagnose illness. The illnesses depicted on the show aimed to be representative of actual illnesses, but were still fictionalised. Specific symptoms are also part of a constellation of symptoms that might comprise an illness, so one symptom alone (ie low blood pressure) isn't enough for a diagnosis and needs to be considered in the context of other symptoms and the individual's health/lifestyle etc...

The medical system (no matter where you are in the world) can be very difficult and frustrating to navigate, so I understand the need to turn to alternative sources for answers. Just be sure that you are critical of the sources you are consuming.

I'm happy to help try identify the episode though. Can you be more specific about the episode/patient/season even? A few POTWs have had that symptom, in various forms...

Here is a list of the diagnoses for every episode, in case that helps: link