Sickly cruise ship passengers are clogging up mainland medical waiting rooms and straining local health services as they try to avoid expensive on-board doctors, according to GPs in the Kimberley.

Heather Briggs has operated a GP clinic in Broome for five years and said she could always tell when a large cruise ship had docked.

"It's difficult to suddenly cope with an influx in one day. There was one particular ship this year where we had 20 or so people queueing for an appointment," Dr Briggs said.

"It's difficult, because the hospital can't cope with them, and they're getting quite large in number."

Lesley Parker manages another GP clinic in the town, and said they have had to turn away a large number of cruise ship passengers who were onshore for a day trip.

"We only have five practices in Broome, which are at capacity most of the time, and then when 2,500 people arrive on a cruise ship there's no capacity to serve those people," she said.

"A big issue is that we need to maintain appointments for our own chronically ill, often palliative care patients, so we can't often see the people from the cruise ships who just want to pop in for a 15-minute appointment.

"We really do feel for the people that get off the ship and who are unwell, but I don't know what the resolution is because there just isn't the capacity."

Treatment expensive on board

The situation has come about because most cruise ship doctors are not covered by Medicare, and charge between $200 and $300 per appointment.

A common sight at the Broome port; ambulances waiting to assist unwell passengers. ( ABS News: Joshua Spong )

In a written statement, the Cruise Lines International Association said on-board doctor fees were set at a fair rate.

"The fees charged on board are generally set at a level to cover the expense of providing the service," it said.

"We encourage guests to purchase travel insurance to cover any unexpected medical expenses they may incur during their cruise, and to travel with extra supplies of prescription medication as well."

The Department of Human Services confirmed that only Australian-registered doctors were covered by Medicare, which the AMA described as appropriate.

"These are often international boats, under an international flag, typically in international waters, carrying often an international doctor, so I don't see how Medicare relates to it," AMA WA vice-president Mark Duncan-Smith said.

"If passengers get sick, they should be encouraged to see the doctor on the ship — local health services should be left for local health problems."

Dr Duncan-Smith agreed that passengers should take out travel insurance.

Ambulance paramedics help an unwell cruise ship passenger when it docked in Broome. ( ABC News )

"Travel insurance should cover the cost, so there shouldn't really be a lot of out-of-pocket expense," he said

The ABC spoke to a number of cruise ship passengers including Sandy Daniels, a registered nurse from Perth, who was travelling with her elderly mother.

Ms Daniels said there was a large number of people on board the ship who potentially would require medical assistance.

"The ratio of elderly people is actually very high, lots of people with crutches, and there's a high risk of potential falls … and then you've got the risk of strokes, heart events, all of that is higher because of the age demographics," she said.

In February about 140 passengers on the Sun Princess cruise ship came down with gastro during a round trip to New Zealand, a fortnight after a similar outbreak on the vessel during a previous cruise.

Queensland Health said 140 people became ill, but passengers estimated that number was higher.

Some complained the ship should have delayed the voyage after 90 people suffered from norovirus on the ship's prior trip to Papua New Guinea.