House M.D. Season 1 Episode 22

As a favor to his former adulterous fling Stacy Warner, House drugs her husband Mark who refused to be examined by him. He's diagnosed with brain symptoms that seem to fit encephalitis or Alzheimer, but tests prove inconclusive. Chase found that he took amphetamines. Then a row with Stacy causes Greg to discover that Mark has erratic memory loss. He concludes porphyria is likely, but the only test to justify dangerous therapy is perilous, especially as Mark refuses to take the attack-inducing cocktail.