Suggest Treatment For Vomiting, Diarrhea And Abdominal Pain

Daughter in law is on a sail boat in south pacific west of New Zealand with a crew doing a documentary. She has become very ill .... severe diarrhea, vomitting, sever stomach pain, was able to get to an island where an apparent doctor diagnosed food poisoning, gave her an antibiotic and some tylenol with codeine sent them on there way.... it has now been 29 hours without relief and now having arm and hand tingling and discomfort..... hospital at home here in Canada won t assist unless they can speak to her directly and of course she can barely get up - they do have satellite phone communication however sporadic at sea.... occasional internet connection however while they have a paramedic on board with crew they are reaching out to us to get an opinion from doctor here of course no one is interested.... any suggestions please..... Michael