In House M.D., what rare disease is diagnosed in the season-one finale “Honeymoon”?

In House M.D.’s season-one finale “Honeymoon,” the patient is diagnosed with acute intermittent porphyria.

The episode centers on Mark Warner, who develops severe abdominal pain, weakness, and psychiatric symptoms. House identifies acute intermittent porphyria, a rare metabolic disorder caused by problems in heme production. The diagnosis is memorable because the disease can produce neurological and psychiatric symptoms alongside abdominal pain.

Acute intermittent porphyria is associated with attacks that may be triggered by certain drugs, hormonal changes, fasting, or illness. During an acute attack, patients can experience abdominal pain, vomiting, neuropathy, confusion, or dark urine. Diagnosis commonly involves testing porphyrin-related substances, especially during symptoms.

The title “Honeymoon” refers to the patient’s situation and the episode’s opening circumstances, not to the disease itself. The diagnosis should not be confused with Wilson’s disease, another named metabolic disorder that appears elsewhere in medical fiction and has a different cause and clinical pattern.