Causes

• foods (particularly nuts)
• stings or bites
• drugs, including ^b
  • antibiotics
  • anaesthetic agents
  • contrast media 

Food and insects are common causes of anaphylaxis

Causes	% (95% CI)
wasp or bee sting, or snake bite c	17% to 52%
drugs or vaccines	9% to 30%
nuts	7.4% to 39%
unclear cause	19% (13% to 25%)
other	15% (9.3% to 20%)
latex	3.5% (0.7% to 6.2%)

Certain drugs have a higher risk of anaphylaxis

Outcome	Risk Factor	OR (95% CI)	NNH (95% CI)
possible or probable anaphylaxis d	glafenine independent	53.8 (25.5 to 113.2)	87 (42 to 190)
	amoxicillins independent	12.3 (5.94 to 25.3)	410 (190 to 920)
	diclofenac independent	8.21 (3.73 to 18.1)	630 (270 to 1700)
	penicillins independent	7.28 (3.78 to 14.0)	730 (350 to 1600)
	NSAID independent	4.19 (2.06 to 8.51)	1400 (600 to 4300)
	analgesics independent	3.78 (1.91 to 7.46)	1600 (700 to 5000)