Table 4. Differences in the epidemiology and pathophysiology of anaphylaxis due to food versus non-food causes.

	Food	Medication / iatrogenic causes	Venom sting
Age distribution: anaphylaxis (all severity)	Most common in preschool children, less common in older adults	Predominantly older ages	All ages
Age distribution: fatal anaphylaxis	Young adults into 4th decade of life. Rare in younger children.	Unusual until 5th decade of life.	4th to 6th decade
Symptoms	Respiratory	Cardiovascular (respiratory less common)	Cardiovascular (respiratory less common)
Asthma/atopy	Common	Uncommon	Uncommon
Onset	Less rapid	Rapid	Rapid
Site of Antigen presentation	Usually orogastric route	Usually parenteral route	Parenteral
Triggering threshold dose	++ interperson variability (up to 4 log)	Poor data for medications	Less variability for insect stings
Mechanism	No or relatively modest increases in MCT generally observed	Increased MCT often seen	Increased MCT often seen
Sex	M=F	M=F	M>>F
Ethnic distribution	? higher risk in persons of Asian decent ? more common in male children of African American decent	More common in persons of African American decent	More common in Caucasians