OR... Save the money you would spend going to the doc and getting all the shots and perscription maleria tablets etc...
And spand that on an extra 2 weeks in ton-sai!
Unless you are doing travelling to the north/ jungly part of thailand, I personally dont bother with the maleria tablet thing.. they make you feel like an albino (it seriously hurts to be in the dun while on the tablets), and give you psycho dreams.
Worst thing that could happen in ton-dai is being bitten by dum-dum the skanky dog, or cutting your foot on coral. Rabies and tetnus should do it.
If you've never been there, mkae sure when you rock up at Phuket peir (if your catching a boat), that you ask to go to Ao Nang. If you say "ton sai" they will take you to another beach called ton sai that is on phiphi island...
Once in Ao Nang, then ask for Ton Sai beach.
Take a stubbie holder- or buy one for the price on a night in Ton Sai.
Take poo and vomit tablets, or buy them over there. I found the pharmasists all have pretty good english.
Make sure you ask to see lots of rooms at different "resorts"... they will chuck you in any old one, even though they probably have nicer ones for the same price.
do as much gym climbing as you can before you get there. the extra strenght and jug fondling will pay off.