I have never taken any Anti-Malarials for trips in Thailand, not sure what the story is in Laos...
I think prevention from being bitten is better... long pants and long sleaves, shoes and socks at night... DEET Insect repealant, and mozzie candles in the room...
Doxi makes me sensitive to sunburn, and I don't want to risk the psychotic effects of quinine...
Malarone is very expensive...
Cheers,
Daewoo