The Swiss consume relatively small quantities of antibiotics compared with the rest of Europe, a national research programme has revealed.
But there are large differences in uses between the cantons, both in terms of per capita antibiotic sales and defined daily doses.
The findings are part of a research programme on antibiotic resistance funded by the Swiss National Science Foundation.
In Switzerland, as elsewhere, public health authorities are alarmed by the emergence and spread of bacterial resistance to antibiotics.
The study showed that neighbouring France was the top antibiotics-consuming country. It recorded 30 doses sold per day per 1,000 people, compared with less than ten per 1,000 people in Switzerland.
"Data from analyses shows consumption per capita [in Switzerland] is not very high compared with other European countries," one of the researchers, Giuliano Masiero from Lugano University's economics department, told swissinfo.
"At first sight that might not appear a big problem. However, if we look inside Switzerland, there are huge differences between the cantons when it comes to consumption per capita."
For example, people in canton Geneva swallow more than three times the amount of antibiotics per person than in canton Appenzell Outer Rhodes.
The authors of a programme research paper note that cantons with the highest consumption, including Geneva, Vaud, Neuchâtel and Valais, are generally located in the southwestern part of the country.
Conversely, cantons with the lowest consumption are in the northeast.
An investigation into the cantonal differences showed that there were wide variations that could not be explained solely by epidemiological factors.
Income and education
Data from 2002 suggests that per capita income, price, demographic factors, including the proportion of foreign residents, the density of medical practices, and cultural and educational differences might contribute to an explanation for the regional variations.
"It seems that the more educated people are and the higher their level of education, the more likely they are to consume fewer antibiotics," Masiero said.
Researchers are now analysing local data, that means from smaller areas, to see if results confirm the findings at the cantonal level.
The project on antibiotic resistance is contributing to the current debate on appropriate antibiotic use and may help to define more effective health policies to reduce the resistance phenomenon.
It is due to close at the end of this year.
swissinfo, Robert Brookes
The research paper, published in the Health Policy journal, looks into what determines the regional variations in outpatient antibiotic consumption in Switzerland.
Large differences are observed across Europe.
France, Greece, and Italy show relatively high consumptions.
Austria, Germany and the Netherlands show significantly lower amounts.
A 2003 OECD report suggested that Switzerland has a low consumption rate of pharmaceuticals.
A total of SFr12 million ($9.4 million) was made available over five years for the multidisciplinary antibiotics research project.
The research phase began on July 1, 2001 with work in 21 research groups.
The projects are grouped thematically:
Human and animal health, surveillance and environment
Society, economics and law