1. Allergy & Anaphylaxis

Question 1

Adrenaline

Answer 1

Indications: Anaphylactic reactions, Severe croup

Precautions: NO absolute contraindications to adrenaline in anaphylactic reactions - used in life-saving situations

Dosage :
Anaphylaxis - IM route is preferred as it is safer than IV.
(IV administration may be necessary when response to repeated IM doses and volume expansion is inadequate).
IV needs continuous monitoring of ECG, pulse oximetry and BP. (IV infusion safer than slow bolus)

EpiPen® - Adult, child >20 kg, IM 0.3 mg. Repeat after 5 mins if required.
Child 10–20 kg, IM 0.15 mg. Repeat after 5 mins if required.

IM - Adult, child, 10 micrograms/kg up to 500 micrograms (0.5 mL). Repeat every 3–5 minutes if required.

IV infusion - Adult, child, initially 0.1 microgram/kg/minute, then titrate according to response.

Slow IV injection - Adult, 50 micrograms (0.5 mL). Repeat according to response. Give IV infusion if repeated doses required.
Child, initially 1 microgram/kg (0.01 mL/kg). Titrate dose according to response.

Nebuliser - For upper airway tract obstruction, eg laryngeal oedema.
Adult, child, up to 5 mL (5 mg).

Severe croup
>1 month, neb 5 mL of undiluted adrenaline 1:1000 as a single dose. Repeat after 30 minutes if required.
(Use with prednisolone or dexamethasone).

Counselling:

• Make sure anyone who may need to give you adrenaline is taught how to recognise when you need it and how to give it.
• Call an ambulance as soon as possible after using adrenaline because further doses may be required.
• Keep two adrenaline autoinjectors with you at all times.
• They need to be stored in the dark, between 15°C and 25°C, but not refrigerated; you may need an insulated pouch.
• Note the use by date for your adrenaline and arrange a new supply in advance.

Practice points:

• glucagon may be useful for adrenaline-resistant anaphylaxis in patients on beta-blockers
• EpiPen® training devices are available to assist with education of patients and carers; a written action plan should be provided

Question 2

Cyclizine

Answer 2

Sedating antihistamine

Question 3

Cyproheptadine

Answer 3

Sedating antihistamine

Question 4

Dexchlorpheniramine

Answer 4

Sedating antihistamine

Question 5

Diphenhydramine

Answer 5

Sedating antihistamine

Question 6

Doxylamine

Answer 6

Sedating antihistamine

Question 7

Pheniramine

Answer 7

Sedating antihistamine

Question 8

Promethazine

Answer 8

Sedating antihistamine

Question 9

Trimeprazine

Answer 9

Sedating antihistamine

Question 10

Cetirizine

Answer 10

Non-Sedating antihistamine

Question 11

Desloratidine

Answer 11

Non-Sedating antihistamine

Question 12

Fexofenadine

Answer 12

Non-Sedating antihistamine

Question 13

Levocitirizine

Answer 13

Non-Sedating antihistamine

Question 14

Loratidine

Answer 14

Non-Sedating antihistamine