Eateries must notify customers if they serve cannabis-infused food and drinks, according to the Public Health Ministry.
Dr Rungruang Kitpati, spokesman for the ministry, said on Thursday that the Department of Health had already issued a notice to govern the use of cannabis at eateries.
The notice requires eateries that incorporate cannabis into their food and beverages to inform all their customers in advance. They are required to list all dishes with cannabis as an ingredient as well as the amount used in each dish.
The department advised that fried food should not contain more than two fresh cannabis leaves, while a bowl of soup, a plate of stir-fried food and a beverage should have no more than only one fresh cannabis leaf.
Eateries must also post a warning about cannabis consumption to people under 20 years old, breastfeeding mothers and pregnant women, Dr Rungruang said.
In addition, people who have allergic reactions to cannabidiol (CBD) or tetrahydrocannabinol (THC) substances should take precaution when consuming cannabis-infused food and drinks as they can cause drowsiness. They should avoid driving or working with machines after cannabis consumption, the physician said.
Restaurateurs are prohibited from showing or advertising any message indicating cannabis can prevent or cure illnesses, he said.
"This is to protect both Thai consumers and foreign tourists. When they visit eateries, they must know if the places use cannabis in their cooking, what dishes contain cannabis and how much cannabis is used,” Dr Rungruang said. “They can then decide if they should consume any food or not.”
Cannabis-free eateries should have signs to inform their potential customers, he said.