Readers are invited to write in with their questions about decisions of the Pharmaceutical Benefits Advisory Committee (PBAC). Australian Prescriber publishes selected questions from readers, together with answers from the PBAC. Questions may address issues such as regulatory decisions, pharmaceutical benefits listings and withdrawals.

This exclusive arrangement helps Australian Prescriber readers understand how the contents of the Pharmaceutical Benefits Scheme (PBS, see www.pbs.gov.au) are determined.

Letters and responses are reviewed by the Editorial Executive Committee and may be edited before publication. It may not be possible to reply to all individual questions.

Your question to the PBAC

Sir, - In 1994 the Schedule of Pharmaceutical Benefits was altered so, whereas previously, drugs were listed alphabetically based on generic terms, they were now grouped according to an organ-related classification system. An immediate consequence of this change is the need for the prescriber to first consult the index at the back of the book and then turn to the organ-based listing. This need changes a single-step into a two-step procedure. More important, it also has the effect of encouraging non-generic prescribing, since the older system alphabetical listing was based on the generic name whereas the alphabetical list in the index contains both generic and brand names.

The organ-based classification is often quite arbitrary and does not necessarily concord with usage. For example, sulfasalazine, while approved for use in rheumatoid arthritis, is listed under the classification 'Alimentary tract and metabolism'.

Antibiotics are included in the classification 'General anti-infectives for systemic use', a most extraordinary term suggesting that these drugs have some sort of comprehensive anti-infective properties rather than having activity directed against specific sensitive organisms.

It has been argued that the therapeutic grouping of drugs could have a positive educational value by drawing to prescribers' attention drugs which may be less expensive and have a similar utility. This argument is spurious since many widely used and appropriate drugs are not listed at all in the benefit Schedule and of course there are often non-pharmacological approaches to therapy.

My understanding is that there is widespread dissatisfaction with the current format of the Schedule and I would be most interested in the results of a survey should the PBAC see fit to assess customer satisfaction of the Schedule in its new format.

John B. Ziegler
Department of Immunology/Allergy
Sydney Children's Hospital
Randwick, NSW

PBAC response

We thank Dr Ziegler for his comments - similar sentiments have been expressed by a number of people.

The basic reason for the adoption of the anatomical therapeutic chemical (ATC) format, as explained in the December 1993 and April 1994 editions of the Schedule of Pharmaceutical Benefits when a move to ATC groupings was foreshadowed, was to provide a logical hierarchy of PBS listed drugs so that prescribers would have information on the drugs used for similar purposes in the same section of the book. The former alphabetical listing did not allow this. The PBAC has always considered that the Schedule has an important educational role, both in relation to the restrictions imposed, and to the notes and cautions which are included. The intention of the new format was to further expand this function. It was felt that the listing of drugs in ATC groups would facilitate drug selection and thus increase the book's usefulness, rather than being simply an alphabetical list of drugs currently available for subsidy.

In the longer term, it is also envisaged that the Schedule will be incorporated into a new publication, the Australian Medicines Handbook (AMH). The introduction of this publication is being overseen by the Royal Australian College of General Practitioners, the Pharmaceutical Society of Australia, and the Australasian Society of Clinical and Experimental Pharmacologists and Toxicologists. Prior to the commencement of planning of the AMH, a randomised survey of prescribers was carried out to determine, inter alia, a suitable format. This survey, which elicited views from both general practitioners and various specialist groups, indicated that a format incorporating therapeutic groupings would be acceptable to prescribers. It was considered that a classification by therapeutic use was reasonable, since such a system is already in use in publications such as MIMS.

The ATC system of therapeutic classification has been adopted for use in the AMH because it is used internationally and endorsed by the World Health Organization. It was felt that the use of the same system in the Schedule would facilitate the incorporation of information on pharmaceutical benefit listings into the AMH.

The ATC code can be used in association with the 'defined daily dose' (DDD) as a unit for comparative drug consumption studies and also in the field of adverse drug reaction studies. With uniform coding, comparisons of drug usage can be made between different hospitals, different communities, different States and even different countries. The Australian Register of Therapeutic Goods is also linked into ATC coding.

Therefore, every effort has been made to ensure that the revised classification of the Schedule is consistent with the ATC system. We acknowledge that there are some anomalies in the classification, particularly for drugs with multiple therapeutic uses. As pointed out by Dr Ziegler, the terminology is also somewhat clumsy at times. However, the advantages of an internationally accepted and used classification outweigh these small problems.

Your question to the PBAC

Sir, - The Young Pharmacists Committee of the Pharmaceutical Society of Australia (NSW Branch) notes with concern the proposed delisting of extemporaneous morphine preparations from the Schedule of Pharmaceutical Benefits effective 1 November 1996. We strongly believe that this decision will not be in the best interests of our patients.

Would you be so kind as to:

  • register our protest against this proposal
  • provide readers of Australian Prescriber with information as to why this decision has been taken.

Stephen Hughes
President, Young Pharmacists Committee
Pharmaceutical Society of Australia (NSW Branch)

PBAC response

At its December 1995 meeting, the Pharmaceutical Benefits Advisory Committee (PBAC) considered the current pharmaceutical benefit availability of oral solution formulations of morphine hydrochloride. The PBAC noted that 3 ready-prepared preparations (Ordine 2, Ordine 5 and Ordine 10) are available as restricted benefits, with listings in accordance with those of other morphine preparations intended for oral administration. The restrictions on PBS supply of oral morphine products are intended to allow suitable therapy in patients suffering from severe pain, while limiting abuse as far as possible.

The PBAC noted that Morphine Mixture APF and Morphine Forte Mixture APF were available as extemporaneously prepared benefits without being subject to the same restrictions. The PBAC concluded that this inconsistency would most appropriately be resolved by the deletion of morphine hydrochloride from the drug tariff. It was considered that patients would not be disadvantaged by this change, since ready-prepared oral solutions are available in a range of strengths permitting a range of dosages and dose titration where necessary. The Schedule of Pharmaceutical Benefits also lists 3 capsule formulations of morphine sulfate containing sustained release pellets, which may be administered in liquid or soft food. These are suitable for patients with nasogastric tubes, and those who are otherwise unable to swallow solid oral dosage forms.

In those cases in which the specified maximum quantity or number of repeats is inadequate, the authority provisions may be used in the usual way, provided the patient satisfies the terms of the restriction set down in the Schedule of Pharmaceutical Benefits.