Oral isotretinoin is a highly effective treatment for severe acne, however it is associated with a number of adverse effects, including teratogenicity, increased blood lipids, and transient increases in liver enzymes.1 Baseline and ongoing monitoring of patients is essential for the safe use of isotretinoin. Isotretinoin can be prescribed by General Practitioners under Special Authority criteria. Prior to March 2009, isotretinoin was only available fully subsidised if prescribed by a registered dermatologist.
This report summarises the testing recommendations for patients starting a course of isotretinoin using data from the Ministry of Health National Collections, between July 2011 and June 2012.
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Between July 2011 and June 2012, 8750 primary care registered patients in New Zealand started a course of isotretinoin.*
For this report, we defined a course of treatment as any number of dispensings of isotretinoin with no breaks greater than three months.
Patients in this report may also have had previous courses of treatment with isotretinoin.
Since 2009, isotretinoin has been available for General Practitioners to prescribe, fully subsidised with Special Authority criteria.
Between July 2011 and June 2012, over half of all dispensings of isotretinoin were prescribed by General Practitioners.
Are patients taking isotretinoin being monitored as recommended?
The current recommendations state that patients prescribed isotretinoin should have a full blood count, fasting lipids and liver
function tests performed at baseline (see Note) and at least once during a 16 to 30 week course of isotretinoin.1
Only 47% of patients had all three baseline tests as recommended, and only 13% of patients had all three tests both before and during their
course of isotretinoin treatment.
Percentage of patients with all three baseline tests before treatment with isotretinoin
Percentage of patients who had each baseline test before starting a course of isotretinoin
Data for Sample Medical Centre †
Number of registered patients who started a course of isotretinoin:
Registered patients with baseline tests before commencing a course of isotretinoin:
† Data for your practice includes prescribing by any health professional, including Dermatologists.
Baseline tests should ideally occur within one month prior to prescription of isotretinoin. However, given that this medicine is
predominantly prescribed to a younger population with generally stable health parameters, we extended the time frame for
baseline tests, for the purpose of this report. A patient was counted as having a baseline test if they had the test within one
year before and three weeks after receiving a prescription for isotretinoin. This also encompasses those patients who are given a
prescription and test request form at the same time.
* Testing data for Nelson Marlborough DHB area is incomplete and patients in this area have been excluded from our analysis.
Data sources: Ministry of Health PHO Enrolment, Pharmaceutical and Laboratory Claims Collections (accessed Feb, 2013).
- New Zealand Dermatological Society (NZDS). Isotretinoin. Available from:
www.dermnetnz.org (accessed Feb, 2013).