You should check with the practice nurse at the surgery.
It depends exactly where you are going and what you will be doing

As a base we had to have tetanus, diptheria, polio, hep A and Typhoid.

And also what you have already. There is a variety of injections you should have anyway you might not have had - also you might be up to date without knowing it.

Go see your doctor as they know your history as well - I would never rely on a public forum for medical issues!

have a look at this site. Please also make an appointment with your nurse as Sam said( just had to do that for our next trip )

Have never had any jabs in the six years we have been going , but have packed Imodium in case I had the runs and they were needed all six times!

A Jab for Tetanus, Polio and Diptheria is advised for travelling anywhere in the world(including Europe) I think one jab covers everything and is good for l0 years. Hepatitis A is also now recommended for travelling to most places.
Although anti malaria and Typhoid drugs aren't normally prescribed for Thailand , I always keep the other jabs up to date, but as previous posters said check with the professionals, Better to be safe that sorry.

Was not trying to be a smart ass, Tetanus/diphtheria, polio and measles inoculations should be up to date, what I meant was I did not have an anti Malaria jab, there have been cases of dengue fever reported in Chiang mai but there is no vaccine for that I read.

Been 11 times and never needed immodium...what you eating?

It's the food or water they wash it in I think (salads), only lasts a day or so until stomach adjusts, the rest of the month I am ok.