In Thailand, cannabis, known by the name ganja (Thai: กัญชา; RTGS: kancha), is regulated under the Narcotics Act. As of 2021, medical cannabis can be purchased from licensed retailers, and households can grow up to 6 plants for personal use. While parts of the cannabis plant that contain less than 0.2 percent tetrahydrocannabinol (THC), which includes the roots, stalks, stems, and leaves can be sold or used for food or cosmetics, recreational use remains prohibited and the flowers and seeds must be sent to state medical facilities.
Cannabis appears to have been introduced to Thailand from India, with the similarity of the Thai name to the Indian term ganja cited as evidence. Cannabis has historically been used in south-east Asia as an ingredient, a kitchen condiment, a medicine, and a source of fiber.
Marijuana had been a traditional medicine for centuries before it was banned in the 1930s. Laborers were known to use it as a muscle relaxer. It was reportedly used to ease women's labor pains.
The possession, sale, and use of cannabis was criminalised by the Cannabis Act, B.E. 2477 (1935). The two most salient acts for practical purposes are the Narcotics Act 2522 (1979) and the Psychotropic Substances Act 2518 (1975).
Regulation of consumption
Under the new law, people with approved health conditions can use marijuana after getting a prescription from a certified physician. The new legislation prevents patients from exceeding and carrying on person the quantity of marijuana specified by their physician.
Tourists entering the country can only have marijuana in a form approved by the ministry of health. Ignoring the related regulations may result in stash confiscation only followed by troubles and worries. Tourists need to carry their medical certificates to show the customs officers at the time entrance to the country. Later, they need to get it approved by the FDA.
Regulation of supply
Thai law essentially excludes all foreign companies as well as foreign majority companies incorporated in Thailand from producing, selling, importing, exporting, and processing cannabis. The move has been viewed as an effort to protect local companies from the onslaught of highly resourceful and modern technology equipped foreign actors. The government has demonstrated a shift in its past view of the substance by shifting the licensing authority from the Public Health Ministry to the FDA. Replacing a case-by-case slow approach of drug approval by the ministry to FDA mass licensing mark a significant shift in the policymakers’ mindset. Under the new law, FDA considers cannabis no different from other lawful drugs and issue licenses adopting an easy routine approach. However, without FDA license marijuana is an illicit drug and anyone in possession of 10 kg or more with an intent to sell can get 15 years in prison and a fine of 1.5 million baht (USD$45,000).
Regulation of distribution
On 11th May, Thailand’s first two full-time clinics dispensing cannabis oil for medical treatment were inaugurated. The move is in line with the government’s intentions to promote licensed use of medical marijuana to address various health conditions. These two clinics are an addition to 25 part-time clinics that are operating since the legalization of the drug under the new legislation. If this experience produces promising results, the government is all set to open two more clinics as a part of a planned nationwide network of marijuana clinics.  The people who were using illegal expensive medical marijuana from underground suppliers are most likely to benefit from it. In addition, the FDA has approved all hospitals of the Public Health Ministry to prescribe medical cannabis to people with approved medical conditions.
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