Trends in antimalarial prescriptions in Australia 2002 to 2005

Studies using Australia's Pharmaceutical Benefits Scheme data for pharmacoepidemiological research: a systematic review of the published literature (1987-2013)

PURPOSE

Research using dispensing claims is used increasingly to study post-market medicines use and outcomes. The purpose of this review is to catalogue more than 25 years of published literature using Australia's Pharmaceutical Benefits Scheme (PBS) dispensing records.

METHODS

We searched MEDLINE, PreMEDLINE and Embase and conducted author searches for studies published from 1987 to 2013. Independent reviewers screened abstracts of 3209 articles and reviewed 264 full-text manuscripts. Included studies used PBS dispensing data to measure patterns and/or outcomes of prescribed medicines use or dispensing claims to derive a proxy for a specific disease cohort or health outcome.

RESULTS

Of the 228 studies identified, 106 used PBS claims only (56 using claims-level data and 50 using individual-level data) and 63 studies linked individual-level PBS claims to other health data. Most commonly, studies examined trends in drug utilisation (33%), clinician and patient practices (26%), drug use and outcomes (18%) and evaluations of intervention impacts (17%). Sixty-two percent of studies using individual-level data were based on a subset of elderly Australians. Most studies focused on drug classes acting on the nervous system (36%), cardiovascular system (15%) and alimentary tract (11%). Few studies examined prescribed medicines use in children and pregnant women.

CONCLUSIONS

Pharmaceutical Benefits Scheme claims represent a significant resource to examine Australia's billion-dollar annual investment in prescribed medicines. The body of research is growing and has increased in complexity over time. Australia has great potential to undertake world-class, whole-of-population pharmacoepidemiological studies. Recent investment in data linkage infrastructure will significantly enhance these opportunities.

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.

Disparities exist in the availability of outpatient malaria treatment in Maryland, USA

BACKGROUND

Prior review of pediatric malaria cases in the Washington, DC area raised concern that there may be systematic barriers to the timely procurement of antimalarial medications for those patients being treated for malaria as outpatients. We hypothesized that the local availability of antimalarial medications was not consistent across communities of differing socioeconomic status.

METHODS

We administered a blinded telephone questionnaire to pharmacists in the Maryland suburbs of Washington, DC and assessed the in-stock availability of antimalarial medication. Pharmacies were stratified into categories of population risk, disease incidence, and income.

RESULTS

Pharmacies in high-income ZIP codes were more likely to stock first-line therapy medications (93%, p = 0.03) than pharmacies in moderate-income, low-incidence, low-risk ZIP codes (50%). Moderate-income ZIP codes with high-malaria incidence and a high-risk population (67%, p = 0.35) were no more likely to stock first-line antimalarial medications than pharmacies in moderate-income, low-incidence, low-risk areas (50%). In all, only four (9%) pharmacies stocked quinine. Many pharmacists stated the reason for this discrepancy was that they believed the Food and Drug Administration (FDA) had "pulled quinine off the market."

CONCLUSIONS

In the United States, disparities exist in the availability of outpatient-antimalarial medications. We recommend that a complete outpatient treatment course is dispensed, or the availability of the medication at the pharmacy that the patient will use is verified prior to departure from the clinic or emergency department. Pharmacists and physicians should be aware that the FDA restrictions on the use of quinine sulfate do not apply to its use for the treatment of malaria.

Chemoprophylaxis of Tropical Infectious Diseases

Travelers to tropical countries are at risk for a variety of infectious diseases. In some cases effective vaccinations are available, but for other infections chemoprophylaxis can be offered. Malaria prevention has become increasingly complex as Plasmodium species become resistant to available drugs. In certain high risk settings, antibiotics can be used to prevent leptospirosis, scrub typhus and other infections. Post-exposure prophylaxis is appropriate for selected virulent infections. In this article the evidence for chemoprophylaxis will be reviewed.