Medicines for migraines, stomach ulcers and other conditions will become cheaper next month as the Albanese government adds new treatments to the Pharmaceutical Benefits Scheme.

Health Minister Mark Butler on Monday announced Australians will have expanded access to some medicines from October 1, saving $130 million a year in out-of-pocket costs.

"Listing these drugs on the PBS will improve the lives of thousands of Australian patients and their families," he said.

"The government is making a trip to the pharmacy cheaper for thousands of Australians."

New medicines being listed on the scheme include treatments for types of cancer and growth hormone deficiency in children.

Medication that will become cheaper for people include drugs for migraines, psoriatic arthritis, breast cancer, stomach ulcers, and bipolar disorder.

Up to half a million people with stomach ulcers or acid reflux will pay a maximum of $26.74 , saving up to $6.84 per script for esomeprazole.

The expanded listing of pembrolizumab (Keytruda) used in cancer immunotherapy, will help an average of 500 people a year, who without a subsidy would pay more than $135,000 per course of treatment.

The PBS co-payment will be reduced from the current maximum of $42.50 per script, to a maximum of $30 per script from January next year.