The sixth edition of Antibiotic Guidelines was published in January 1990. Nearly 22,000 copies were sold by June. Experts from all Australian states and territories were involved in its preparation, and all state health authorities endorsed it.

By this time Antibiotic Guidelines was accepted as a national standard.

Professor John Turnidge, an expert in laboratory testing, was added to the writing group which otherwise remained unchanged from the fifth edition. He contributed to ten editions.

Chaired by Laurie Mashford (chair of versions 3–9) the sixth edition carefully considered its general practitioner audience. A VDUAC symposium in 1987 had looked at factors influencing prescribing, and recommended action to help rationalise prescribing in general practice and hospitals. Funding in 1989 from the Commonwealth Department of Community Services and Health allowed the Therapeutics Committee to undertake studies of antibiotic use in Victorian general practice. The effect of Antibiotic Guidelines on prescribing behaviour was considered in groups of general practitioners. One group was subjected to an intervention campaign to encourage the prescribing of narrow spectrum drugs, in preference to broad spectrum or expensive antibiotics, for treating tonsillitis. Funded by VDUAC, general practitioners in that group received five separate mailings of eye-catching posters and brochures, and a visit from the project pharmacist. A subsequent analysis of their prescribing habits revealed increased prescribing of penicillin and erythromycin.

The fifth edition of Antibiotic Guidelines, released in 1987, was accompanied by the slogan ‘It’s best to be narrow minded about tonsillitis’. The edition included a section for general practitioners, and was jointly authored and endorsed by experts and health authorities in New South Wales, Queensland, South Australia and Victoria.

More than 500 hospitals in Australia were told of the new edition and were given posters to display, as well as brochures to encourage the booklet’s purchase and use. Advertisements were also placed in major medical publications. Complimentary copies of Antibiotic Guidelines continued to be provided to new interns assigned to Victorian teaching hospitals at the beginning of each year. By the end of 1987, almost 18,000 copies had been sold.

In 1988 the Commonwealth Government agreed to purchase and distribute 28,000 copies of the fifth edition of Antibiotic Guidelines free to all medical practitioners in Australia with the August edition of the Pharmaceutical Benefits Schedule.

The mass government distribution represented an enormous breakthrough in the national acceptance of the guidelines.

Total sales exceeded 50,000 by the end of 1988. Bulk orders were placed by several medical and biological science teaching institutions for 1989 students.

A specially scripted 10-minute film titled ‘Proceed with caution’ was made in 1985. Costing around $15,000, and filmed at The Royal Children’s Hospital in August 1985, the script was written by Scali, McCabe, Sloves. The film used comic exaggeration of the Monty Python genre, and sent up surgeons, the pharmaceutical industry, patients, students and the excesses of antibiotic prophylaxis focussing on proper timing. A scene of exaggerated and unnecessary antibiotic treatment for a patient was followed by an exchange between a cleaner and a pharmacist in which the cleaner, who has read copies of the Antibiotic Guidelines he’s seen lying around, quotes them chapter and verse. Its aim was to trigger discussion among staff at the hospitals which participated in the 1985 Antibiotic Project. This it certainly did.

‘Proceed with caution’ was entered in the International Television Association Awards in 1985 in the training film category and won a silver award.