(Does anyone drink Chianti without thinking a little bit of Dr. Lecter? Just wondering.)
Favism is a disease where people's red blood cells rupture (called hemolysis) when they eat Fava beans.
The basis of the disease is a deficient enzyme called G6PD (glucose 6-phosphate dehydrogenase) which is necessary for red blood cell membrane health. It's linked to the X-chromosome, which means mostly men get the symptomatic disease.
During a hemolytic crisis when a person's red cells rupture, the sufferer can have symptoms such as jaundice (yellow eyes and skin), paleness, weakness, fatigue, shortness of breath, chest pain, or fainting.
People with G6PD deficiency can have the same reaction to medications such as anti-malarials, sulfa-containing drugs, aspirin, and some antibiotics.
Favism has been known since antiquity as a cause of anemia. The ancient Greek philosopher Pythagoras recommended abstinence from Fava beans, possibly to avoid this disease.
This would be a pretty elaborate way to incapacitate a fictional character who was susceptible. Hide some Fava beans in brownies, maybe?