What should I take with me Bagpacking in Thailand?

You don't need any vaccinations to visit Thailand but you already got them they don't hurt of course. Malaria is not a problem anywhere except near the Cambodian border on the east and Myanmar border on the west so forget about malaria unless you are going to those places.

You can get almost everything you need in Thailand and it will be cheaper. Almost all types of medicine including antibiotics are available over the counter at pharmacies and pharmacies are found throughout the country even in small towns. So pack only a small amount of things you will need when you first arrive and then buy the rest local as you need it.

One thing you might want to pack is bed bug spray. Bed bugs have been reported as a serious problem by many backpackers. There is a good product at the link that comes in small backpack size spray bottles.

As little as possible as it will be a pain to carry it all around. You can take your clothes to be washed at a laundry and they are very quick. I would take some anti septic mouthwash as this is also good for insect bites. And always carry toilet paper

Just a backpack with clothes in it, everything else you can get over here as you realize you may need it and it's all cheaper over here. If you have big feet then bring an extra pair of shoes, that was my biggest problem was finding size 13's when mine were stolen and when I finally found some they were over $100, what would have been $50 in the USA.

Sun Screen
Passport
Bikini
Panties
T-back

Hi there, I suggest to bring comfortable clothes, bring your vitamins, buy some mosquito repellant because there are some places in Thailand where there is flood. Don't forget to bring pocket money good for a month or more than that. Stay with your buddy always.

Don't forget this the do's and dont's:

I was just in Bangkok in November. Bring antibiotics, like doxycycline, especially if your going to be traveling anywhere outside of Bangkok. The country is incredibly dirty and theres a lot of mosquitoes, so I'd deet treat your clothing before leaving also (depending on if you're going north or not).

Otherwise everything is easy to get. So just pack shorts/jeans and T-shirts. You'll be overdressed in anything else.

As a side note stay together with your travel buddy. I traveled with one other guy like you and I cut my foot open and it got crazy infected one night (because its so filthy everywhere). Also, my buddy got jumped and robbed one night when I came home early.

Tissues, might not be any in tOilets there.
Facial wipes
Mouth wash
Fly spray
Anti histamines
Paracetamol
Sleeping tablets
Laxatives
Deodorant
Hydration tablets incase you get food poisoning - dioralite.

Backpaking in Thailand? Make sure you taken your malaria tabs before you go for starters and get any nessesary shots.
A heavy duty combination padlock. A money belt. Resealable plastic bags to keep things dry. Plenty clean socks to avoid blisters. Duct tape (essensial for repairs to anything from bag rips to life threatening wounds), painkillers, first aid kit, superglue (handy for small cuts/repairs), roll of electrical tape, mosquito repellent, desert hat, and most importantly, CONDOMS FOR THE LADYBOYS coz they so haw-nee ;)