Trends in antimalarial prescriptions in Australia from 1998 to 2002

Trends in antimalarial prescriptions in Australia, 2005 to 2009

BACKGROUND

Malaria continues to represent a significant risk for some travelers and malaria chemoprophylaxis has remained an important countermeasure. Trends in antimalarial use may be influenced by a number of factors, including the availability of antimalarials, increasing resistance, the issuing of updated guidelines for malaria chemoprophylaxis, and continuing education. The aim of this study was to investigate the trends in prescription of antimalarial drugs, particularly those recommended for chemoprophylaxis in Australia, from 2005 to 2009.

METHODS

In 2011, data were extracted from the online Australian Statistics on Medicines reports published by the Pharmaceutical Benefits Advisory Committee, Drug Utilization Committee, on antimalarials used in Australia for the period 2005 to 2009.

RESULTS

Among the drugs solely used as antimalarial drugs from 2005 to 2009, atovaquone plus proguanil and melfloquine were the most commonly prescribed antimalarials. Mefloquine prescriptions increased by 38% from 2005 to 2008 before decreasing by 17% from 2008 to 2009. The number of prescriptions for atovaquone plus proguanil has trebled during the period. Prescriptions for proguanil have dropped over 90% from 2005 to 2009. The diaminopyrimidines, pyrimethamine-containing antimalarials, have mostly been removed from the prescription drug list. Prescriptions for chloroquine have reduced by 66% from 2005 to 2008 and chloroquine was only available on special access from 2009. Artemether plus lumefantrine combination has been used in relatively small quantities and only on special authority from 2007 to 2009. Quinine prescriptions have fallen by 60%. Although a considerable quantity of doxycycline was prescribed, it was unknown how much was intended for malaria chemoprophylaxis.

CONCLUSIONS

The prescription of antimalarials in Australia was consistent with the national guidelines with the most commonly prescribed antimalarials being atovaquone plus proguanil, mefloquine, and most likely doxycycline. Other antimalarials previously used for chemoprophylaxis have continued to be removed from the prescriber list between 2005 and 2009. The prescriptions of quinine may be becoming displaced by newer antimalarial drugs for treatment, but this needs further investigation.

Trends in antimalarial prescriptions in Australia 2002 to 2005

BACKGROUND

Prescribing patterns of antimalarial drugs have previously been observed to vary considerably in Australia. The aim of this study was to investigate the trends in prescription of antimalarial drugs recommended for chemoprophylaxis in Australia from 2002 to 2005.

METHODS

In 2007, data were extracted from the online Australian Statistics on Medicines reports published by the Pharmaceutical Benefits Advisory Committee, Drug Utilization Sub-Committee on antimalarials used in Australia for the period 2002 to 2005.

RESULTS

Doxycycline probably remains the malaria chemoprophylaxis of choice prescribed for Australians visiting multiple drug-resistant malarious areas. Over the past 15 years, there has been a marked drop in the prescription of less useful antifolate drugs, such as pyrimethamine-containing antimalarial drugs. There has also been a reduction in the number of prescriptions of chloroquine and proguanil, although the downward trend in prescriptions of mefloquine appears to have arrested and has trended upward. The number of prescriptions of atovaquone and proguanil has been increasing dramatically, particularly since inclusion of this combination antimalarial in the prevailing Australian guidelines. Artemether plus lumefantrine combination is now available, but it is used in relatively small quantities.

CONCLUSIONS

The prescription of the antimalarial drugs, proguanil, chloroquine, and the pyrimethamine-containing compounds, has generally reduced in number. Prescription of mefloquine trended upward during 2002 to 2005, following a period of reducing prescriptions. The atovaquone plus proguanil combination has steadily increased in use and is presumably displacing older antimalarials. The use of quinine has halved, which might be related in part to the uptake of newer antimalarial drugs for treatment. Trends in antimalarial use may be influenced by a number of factors, including the availability of antimalarials, increasing resistance, the issuing of updated guidelines for malaria chemoprophylaxis, and continuing education.