Virtually every cruise ship (except for some smaller vessels operating in coastal waters) has a fully equipped medical facility and staff to handle medical emergencies. The facility is more like a health care center or ambulatory care unit which they deal with sprained ankles, stitches, upset stomachs and people who have forgotten to pack needed medication.
The equipment you will find at shipboard medical centers includes defibrillators, cardiac monitors, external cardiac pacing capability, a ventilator, oxygen tanks, x-ray machines and lab equipment. There will also be wheelchairs and stretchers.
Pharmacy supplies include seasickness pills, aspirin and other over-the-counter products, antibiotics and limited supplies of prescription medications, as well as emergency medications such as those needed for advanced cardiac life support.
The cost of medical treatment will need to be paid at the time of service and will be billed to your shipboard spending account. It is strongly recommended to purchase travel insurance to cover unexpected medical issues, as these services are not covered as part of your cruise fare.