Is a life threatening clinical response that appears within minutes after administration of substance(s) to which the subject has been sensitized. Common offenders are drugs (e.g. penicillin), vaccines, insect stings and blood products.

Clinical features: These include respiratory distress due to oedema of the hypopharynx and larynx or bronchospasm and vascular collapse. Others include pruritus and urticaria.

Treatment Guidelines:

Any delay in recognition/diagnosis and prompt treatment may lead to death. Immediately do the following:

• Adrenaline 0.5-1 mg I.M. repeated every 15 minutes until improvement occurs.

• Laying of patient flat and elevating feet.

• Restoration of blood pressure - with I.V. infusions

• Chlorpheniramine 10-20 mg I.V. stat.

• Oxygen may be required in severe respiratory embarrassment (4-6 l/min)

• Hydrocortisone 200 mg. I.V. every 6 hours for 24 hours would prevent further deterioration.

• Prevention can be achieved by taking relevant history before administering materials known to produce a high rate of anaphylaxis. Skin test should be done when in doubt.

• Patients should be asked to always mention allergies for drugs when visiting a clinic/prescriber.