Police say the trio crossed just after 5pm on Saturday, with one of them claiming to need urgent medical attention, although they later failed to attend the nominated medical centre.

Their ute was found at a hotel in Mawson Lakes just after midday on Sunday.

The two men, aged 34 and 35, were found a short distance away in a taxi and the 32-year-old woman was located in Merchant Lane.

The men were taken to the Royal Adelaide Hospital for treatment - one for a check-up and the other for a pre-existing ankle injury - while the woman was taken to the City Watch House.

All three are expected to be charged and will also be tested for coronavirus.

Meanwhile, the state government says testing will be available at up to five pharmacies during a two-week trial.

Health and Wellbeing Minister Stephen Wade says the pilot program will capitalise on the trust pharmacists have within the community to improve access to COVID-19 testing.

"People often present to a pharmacy with mild cold or flu-like symptoms to seek advice from their pharmacist or to obtain treatment for symptom relief, and these are the very people we want to get a COVID-19 test," he said in a statement.

"We want to build on our network of more than 60 COVID-19 testing locations in South Australia to make it as easy as possible to get a test."

South Australia's chief pharmacist Naomi Burgess said a training program had been developed to train pharmacists in swab collection.

"A number of infection control measures will be put in place, including ensuring pharmacies have enough personal protective equipment, swabs and pathology specimen bags," she said.

Customers must have a smartphone and register with the SA Pathology Personify website to receive their result.

The service will not be promoted and pharmacists will identify candidates on a case-by-case basis.

Australian Associated Press