Allergy and anaphylaxes

Question 1

In a patient with known penicillin allergy what are the other classes of antibiotics which they may cross react to?

Answer 1

• cephalosporins (more likely) (1st and 2nd gen deffo not, 3rd gen caution)
• beta-lactams (carbapenems)

Question 2

How long should you observe a patient once treated successfully for an anaphylactic reaction?

Answer 2

6-12 hours as they may have a rebound reaction

Question 3

A patient already has uticaria, what drugs may aggravate it?

Answer 3

• NSAIDS

- Opioids

Question 4

What is the mostly likely drug causing a allergic reaction in anaesthetics? What else must you consider with allergies to anaesthetic agents?

Answer 4

• rocuronium
• no of the drugs used should be re-administered in patients whom had anaphylactic reaction during anaesthetics UNTIL there has been investigations into the causative agent

Question 5

define anaphylaxis.

Answer 5

Anaphylaxis is a severe, life-threatening, generalised or systemic hypersensitivity reaction.

Question 6

what is the difference between a mild anaphylaxis and severe?

Answer 6

Severe has an element of systemic shock

Question 7

What is the first line treatment for mild anaphylaxis?

Answer 7

10mg oral chlorphenamine

Question 8

What is the the treatment for severe anaphylaxis?

Answer 8

500mcg IM adrenaline
10 mg IV chlorphenamine
200mg IV corticosteroids

Question 9

What patient follow up must occur after an anaphylactic reaction in hospital?

Answer 9

• 3/7 oral pred
• 3/7 non-sedating anti-histamine
• medical alert band if likely re-exposure
• document the allergy thoroughly
• prescribe 2 adrenaline auto-injectors if re-exposure is likely

Question 10

When do you refer to an allergy specialist?

Answer 10

• any severe reaction
• any reaction occurring during or immediately after anaesthesia
• when future treatment may become complicated because of allergy (specific disease and ABX)

Question 11

When do you take tryptase mast cell blood tests?

Answer 11

• take 2
• 1 - as soon as possible after emergency treatment has been started
• 1 - 1-2 hours after the first blood test

Question 12

What is there to be said about IgE testing for allergies?

Answer 12

• positive results is likely of a true allergy
• negative result could be false negative
• positive history + IgE test is most likely an allergy