Unpredictability of Attacks

Unpredictability of HAE attacks

A hereditary angioedema (HAE) attack can happen at any time without warning, and there is no way to tell how severe the next attack will be.1

Triggers – Some triggers have been identified and may include2-5:

  • Stress
  • Physical trauma, surgery, or a dental procedure
  • Infection
  • Hormonal influence
  • Mechanical pressure

Frequency – The severity and frequency of HAE attacks vary greatly from patient to patient and can also change over time.6,7 A 2007 survey found that patients experienced a mean of 27 attacks per year.8,a

Severity – HAE attacks can be unpredictable.3 When untreated, the swelling of an HAE attack typically develops during 12-36 hours before it plateaus and then gradually subsides during the next 2-5 days.9 Attacks can migrate to other parts of the body during a single attack.3,7

Laryngeal attacks pose the greatest risk and put patients in danger of asphyxiation.7 About 50% of HAE patients experience at least one laryngeal attack in their lifetime.5,10,b

aIn a survey of 399 patients.8
bIn a survey of 209 patients.10