Symptoms & signs of anaphylaxis include

• Tight or constricted breathing
• Swelling of the tongue
• Difficulty speaking and sometimes a hoarse voice
• Swelling or tightness in the throat
• Rapid heart rate and low blood pressure
• Loss of consciousness/collapse
• Pale appearance and floppiness in small children or babies

Sometimes there may be milder signs of allergy before the above symptoms start, which can include:

• A tingling sensation around the lips or mouth.
• Hives or welts
• Abdominal pain and vomiting (although these are viewed as signs of anaphylaxis in the case of insect allergy)

In around 1 in 5 cases, there may be a second bout of anaphylaxis within 12 hours of the first. This is called biphasic anaphylaxis.