The Turnbull government has found money to list a drug for spinal muscular atrophy on the PBS, roll out a free whooping cough vaccine and help Lifeline.

Sufferers of spinal muscular atrophy will have access to a life-saving drug for a fraction of the cost, as the government makes a suite of pre-budget health announcements.

Spinraza will be made available on the PBS from June 1 this year for all patients under 18, Federal Health Minister Greg Hunt revealed on Sunday.

"It can be a slow and agonising condition but today is a day about genuine hope," he told reporters in Melbourne.

It would have cost more than $367,850 a year for the medicine but it will now be $39.50 per script with concessional patients paying $6.40.

The government subsidies will cost the budget $241 million but Treasurer Scott Morrison says it will help families deal with "a heartbreaking condition".

"For these kids, for their families there is no more essential service than keeping their kids alive," he told the Nine Network.

Mr Morrison took a particular interest in the push to list Spinraza after hearing about it at a forum in Canberra and within his own electorate.

"I looked a lot more into it," he said.

"I sat down with Greg Hunt and the prime minister and others and we said 'this is something you need to do'.

"This is what a stronger economy can do. It can prolong the life of young kids."

The government is also finding the money to deliver free whooping cough vaccines for every pregnant Australian woman from July.

The vaccine is being added to the national immunisation program at a cost of $39.5 million.

"There are now no barriers and no excuses for not protecting yourself, your family and the rest of the community," Mr Hunt said.

The announcement follows the campaigns by two families whose babies died after contracting whooping cough.

Catherine and Greg Hughes' son Riley died of whooping cough in 2015, while David and Toni McCaffery lost their four-week-old daughter Dana in 2009.

Ahead of Tuesday's budget, Malcolm Turnbull and Mr Hunt pledged a $33.8 million cash injection to boost mental health service Lifeline's 24-hour telephone service.

The funding will help the charity answer more calls and train more staff.

The prime minister praised the work of the organisation's thousands of volunteers.

"Their love changes and saves lives," he said in a social media video about the announcement.

Mr Hunt was tight-lipped on the details of an expected package for aged care in the budget.

"We are very, very focused on a strong aged care package which includes support in home and in residential care," he said.

Readers seeking support and information about suicide prevention can contact Lifeline on 13 11 14.

Suicide Call Back Service 1300 659 467.

MensLine Australia 1300 78 99 78.

Multicultural Mental Health Australia www.mmha.org.au.

Local Aboriginal Medical Service details available from www.bettertoknow.org.au/AMS