Most westerners are fortunate to have obligatory medical insurance. When you are in Thailand, see to it that cash or credit cards are always available and have on hand the most pertinent medical insurance documents. In cases of hospital admissions, you are required to pay up front treatment.
There have been stories appearing in a local Thai newspaper about a young Thai couple that was turned down upon arriving at a private hospital just because they could not show their money. This is a major ethical flaw in Thailand’s health care system.
Although general treatment and admission to private hospitals is quite simple, demanding money up front may be considered very impolite and inappropriate. In most European countries, problems like these are normally avoided because in the first place, patients have obligatory medical insurance and hospitals are confident enough about being paid. Staying in Thailand is generally very desirable however some health care issues are quite concerning.
In order to avoid problems, see to it that you already have in place international health care system insurance before you relocate to this Southeast Asian country. Then you will not have to worry about health issues, especially in a medical emergency.