I'd make sure I'm up to date on all immunizations, especially tetanus. I travel enough (every couple years at least) that I'm also always covered by typhoid inoculation. Not sure if that's an issue in Fiji though.
I'm curious about antibiotics for intestinal bacterial infections. My doc always gives me azithromycin. Now I'm wondering if I should have had something different for Indonesia last August.
I've used it twice: Once in a very remote location where a charter sailboat pulled up to our tiny island with a very sick tourist on board. I gave her my meds, but we ultimately had to evac her to a real clinic for IV hydration, at night, over a shallow reef. The second time was on the airplane home. I made the mistake of getting a milkshake that was a bit warm by the time I drank it....
Also check the US CDC web site. It's really helpful.
Beyond that, I'm often packing a little first aid kit for a group so I have way more than I'd carry for myself. For me, I'd take tylenol, benadryl (or your antihistamine of choice), and some other allergy meds specific to my needs. I take some rubbing alcohol to clean out my ears and some antibiotic ointment.
And duct tape. Always carry duct tape. It is great for a number of medical and non-medical purposes....