Hay fever affects about 15 per cent of the population but experts say most sufferers remain undiagnosed.
Typical symptoms include a blocked or runny nose, sneezing and watery eyes but the condition can also cause sleep disturbances and headaches.
A flowering plant expert at Melbourne University, Associate Professor Ed Newbigin, said the severity of this year's hay fever season would increase with spring rain.
While grasses are not yet flowering, European trees such as elms, birches and alders had already begun, Dr Newbigin said.
Read more: The Age Newspaper