benzyl benzoate burns bad: 415 poison centre adverse

Benzyl benzoate burns bad: 415 poison centre

adverse reaction reports and counting

Jared Brown, Christopher Johnston New South Wales Poisons Information Centre

Sydney Children’s Hospital Network, Westmead, Australia

References and Further Information 1. Strong M, Johnstone P. Interventions for treating

scabies. Cochrane Database Syst Rev 2007; 18:

CD000320.

2. TGA Database of Adverse Event Notifications. www.

Date accessed: 24 April 2014.

3. Scabies [revised Feb 2009]. In: eTG complete

[Internet]. Melbourne: Therapeutic Guidelines

Limited. Accessed 5 May 2014<etg.hcn.com.au>

Jared Brown, Senior Poisons Specialist (Research and

Audit), NSW Poisons Information Centre, Sydney,

Australia. Email: jared.brown@health.nsw.gov.au

Discussion

Benzyl benzoate is a cause of

significant pain and distress in

both adults and children

• Since 2000, the Therapeutic Goods

Administration and NPS Adverse

Medicine Events Line only had 5 ADRs

reported in total.

• TGA Database of Adverse Event

Notifications 1975-1999: 46 cases of

mostly skin reactions.

• Topical permethrin for scabies has a

significantly larger market share in

Australia but only 24 cases of ADRs

reported to NSWPIC in the same time

period and 6 reports to TGA.

• Reactions to benzyl benzoate are

grossly underreported through

traditional reporting mechanisms

(consumer, health professional and

pharmaceutical industry)

• PICs are an underutilised public health

surveillance system for ADRs.

• Adequate labelling and counselling for

consumers on appropriate first-line

therapy (ie permethrin)3, correct usage

and possible adverse effects is vital.

• Follow-up of cases would improve

understanding of the ADR duration and

outcomes along with strategies to best

prevent and treat reactions when

benzyl benzoate is indicated.

Results summary

• 415 cases identified

• 390 involved skin reactions

• 38 involved ocular reactions from

accidental contact with eyes after

skin application

• 56% female

• 60% children : 40% adults

• Paediatric cases were evenly

spread over all ages

Disposition at time of call:

• 26 attended hospital

• 26 called an ambulance

• 16 referred to hospital

• 9 referred to general practitioners

• 2 attended general practitioners

Background

• Benzyl benzoate is a topical

treatment for scabies and body

lice.

• The two Australian formulations,

Ascabiol and Benzemul are both

25% concentration, dilution is

recommended prior to use for

children.

• The limited clinical trial data on

its use (10-25% concentration)

suggests similar effectiveness to

permethrin.1

• Dermatological adverse reactions

are reported but were classed as

minor with an incidence of

0-38%. 1

Objective:

To describe the nature and frequency of adverse drug

reactions to topical benzyl benzoate in Australia

Methods

• Retrospective review of calls to NSW

Poisons Information Centre during

1 January 2004 – 31 December 2013.

• NSWPIC takes calls mainly from New

South Wales, Tasmania and the

Australian Capital Territory, and after-

hours calls on a rotating roster from the

remainder of Australia (represents 50%

of national call volume with an annual

call volume of ~105,000).

• Inclusion criteria: Suspected adverse

reactions from therapeutic use of

topical benzyl benzoate.

• Poisons Database search strategy:

Substance code of benzyl benzoate

Free text search for “Ascabiol”,

“Benzemul” or “benzyl” with

“benzoate” Signs and symptoms recorded by

NSWPIC as part of suspected

adverse drug reactions from benzyl

benzoate use (N=415)

Number of adverse drug reactions to topical benzyl benzoate

reported by year and age category to NSWPIC (N=415)

Reaction Number

Burning/stinging sensation

282

Screaming/crying 100

Skin redness 72

Pain 69

Skin irritation 36

Ocular irritation 36

Rash 19

Itch 9

Nausea 4

Skin swelling 3

Skin blistering 2

Dizziness 2

Abdominal pain 2

Welts 1

Fainting 1

Visual acuity decreased 1

Unable to open eyes 1

Facial hair loss 1

Headache 1

Drowsiness 1

0

10

20

30

40

50

60

70

80

2004 2005 2006 2007 2008 2009 2010 2011 2012 2013

Child

Adult