It remains unclear whether CSL would be directly impacted by the US president's proposed 100 per cent tariffs, which he announced in a post on social media.
CSL, Australia's seventh-largest public firm by market capitalisation, makes up the bulk of Australia's $2.2 billion pharmaceutical export trade to the US.
The ASX blue-chip stock's main exports to the US are medicines derived from blood plasma manufactured at its plant in Melbourne.
The firm also has a substantial footprint in the US, where it employs 19,000 staff, or about two thirds of its overseas workforce.
Health Minister Mark Butler said the government was still working to understand the implications of the announcement for Australian exporters.
"We've been making the case, since it first became clear that the US was going to take some action in this area, about the benefits of continued free trade in pharmaceuticals between our countries," he told reporters in Adelaide.
Due to prohibitions on sourcing blood plasma in Australia, CSL collects plasma in the US, ships it to its Melbourne factory and ships back the final product.
Most vaccines CSL sells in the US are produced at its vaccine-manufacturing plant in North Carolina and the company has announced further expansion plans in America.
The company said it was confident it would be exempted from the imposts, given Mr Trump said companies building manufacturing facilities in the US would not be impacted.
"CSL will be actively monitoring further announcements from the administration in relation to the detail of the tariffs," a CSL spokesperson said in a statement. Â
"As per previous market guidance, we do not expect any material impact from these tariffs."
Mr Trump said a 100 per cent tariff would be imposed unless a pharmaceutical was building a manufacturing plant in the US by October 1.
Citi healthcare analyst Laura Sutcliffe said CSL had flexibility to move around steps in its manufacturing structure if needed to adapt to the tariffs, although there were questions around whether its supply chain was insulated from impact.
CSL's share price slumped 3.6 per cent shortly after the stock market opened, before retracing some of its losses to sit 1.7 per cent lower by late morning.
Trade Minister Don Farrell spoke with US trade representative Jamieson Greer on the sidelines of the ASEAN summit during the week, but there was no indication from the Americans about an impending tariff announcement.
The opposition said it was deeply concerning that exporters could be subjected to "harmful" tariffs and stood ready to help the government protect Australia's pharmaceutical sector.
US pharmaceutical companies lobbying the White House have previously put Australia's Pharmaceutical Benefits Scheme in their crosshairs, arguing the government program unfairly suppresses prices.
The Albanese government has flatly refused any negotiation on the PBS.
"None of these latest announcements from the US administration make a jot of difference to our determination to protect the PBS," Mr Butler said.
Pharmaceutical industry body Medicines Australia opposed the tariffs but was more concerned by Mr Trump's "most favoured nation" proposal, which would force companies to lower US drug prices to the lowest international benchmark, potentially threatening the PBS.
"This is already impacting Australian patients access to new innovative treatment options - with decisions being made to slow new products launching in Australia which will exacerbate the delays to listing on the PBS," said chief executive Liz de Somer.
Mr Trump also announced 50 per cent tariffs on kitchen cabinets and vanities and a 25 per cent tariff on all "heavy (Big!) trucks" imported to the US.
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