A controversial anti-malaria drug which has a history of worsening mental health conditions is reportedly being given to asylum seekers on Manus Island.
Mefloquine or Lariam, which is taken weekly, has been prescribed to asylum seekers from 2012 onwards, the ABC reports.
There have been calls for an investigation into the drug's use in the Australian Defence Force, following its links to depression and hallucinations.
The immigration department says asylum seekers and refugees are told about the side effects of the drug and monitored for adverse reactions.
There is a comprehensive mosquito control program at the island's detention centre which includes fogging, bed nets and removal of still water.
The department is considering how to make two other malaria drugs, which require daily consumption, available to detainees so they can make the personal choice about which one to use.