Opposition Leader Bill Shorten denounced the Turnbull government's cuts to pathology services during a visit to Launceston Pathology on Friday.
A spokeswoman for the Federal Department of Health said that "pathology providers that provide Medicare eligible services will receive between $1.40 and $3.40 less for each patient episode that is bulk billed" from July 1, 2016.
Mr Shorten said these cuts could necessitate co-payments from pathology providers and deter Australians from important medical tests.
"There is no good case for undermining the quality of Australians' and Tasmanians' healthcare by putting barriers in the way of patients seeking necessary tests," Mr Shorten said.
"Tasmania already has challenges in terms of health and life expectancy and health outcomes, and the Liberal government, in my opinion, is behaving in a cowardly fashion."
A spokesperson for Health Minister Sussan Ley said Mr Shorten is misleading the public.
"Bill Shorten needs to explain why Labor continues to mislead the Australian public after their $550 million cut to Medicare-funded pathology services in office and how the ALP can therefore justify opposing the Government's sensible MYEFO measure," they said.