Cannabis has histories as a fibre crop, an intoxicant and a medicinal ingredient. Evidence for one use does not prove another. A piece of hemp fabric establishes something different from a medical text, and a medical text records a practice rather than demonstrating that it works by modern clinical standards.
This timeline uses identifiable sources instead of assigning a single, certain date to the “first medicinal use.” It also separates older Thai rules from the framework a patient encounters today.
Early evidence: material remains have limits
A 2019 archaeological study analysed residues in wooden braziers at Jirzankal Cemetery in the Pamirs, dated to about 2,500 years ago. The findings support cannabis burning in a funerary or ritual context. They do not identify a medical diagnosis or demonstrate a treatment effect. Original archaeological research.
Stories assigning precise ancient dates to legendary rulers should be distinguished from dated physical evidence and surviving texts. Our previous article presented several such dates as established facts. We no longer use them to claim a confirmed first prescription or first cure.
The same caution applies to plant remains: seeds, fibres and chemical residues need their archaeological context. Presence alone cannot tell a reader the purpose, dose or outcome of use.
Nineteenth-century medical writing
William Brooke O'Shaughnessy's report on Indian hemp, published in the Provincial Medical Journal in 1843, is a primary record of observations and experiments involving cannabis preparations. It documents an important episode in the exchange of medical knowledge between India and European medicine. The original 1843 publication.
Read the paper as a historical document. Its disease terminology, methods and assumptions belong to its period. Case descriptions do not provide a modern treatment protocol, and the author's judgments about societies should not be repeated as present-day facts.
The previous version borrowed sweeping language about some populations using cannabis for crime or vice. It also gave an unsupported percentage increase in use among young people. Those statements have been removed rather than dressed up as historical certainty.
Thai traditional preparations
Thai traditional medicine includes named preparations containing cannabis. DTAM's published product information identifies formulas and preparations rather than treating every cannabis product as interchangeable. DTAM information on cannabis-containing preparations.
This matters when reading older accounts. A formula containing several ingredients is not the same as isolated CBD, a modern extract or a smoked flower product. Evidence about one cannot automatically be transferred to another. Our traditional-medicine patient guide explains what to ask about a proposed preparation.
Thailand's recent legal milestones
| Period | Documented development | How to read it |
|---|---|---|
| 2019 | The Narcotics Act amendment enabled specified medical and research activity | A historical permission framework, not today's complete rulebook |
| 2022 | Changes to the narcotics listing altered the treatment of cannabis, with extract exceptions | Delisting and unrestricted permission are different concepts |
| 2025–2026 | Controlled-flower rules and establishment guidance define medical access and operator duties | Use the current instruments for present decisions |
The Thai FDA's explanation of the 2019 framework is contemporary evidence of the medical and research permissions at that time. Its historic penalties and licence counts should not be applied to today's reader without checking later law.
The FDA's 2022 explanation describes the relevant extract exception. For current access, use DTAM's establishment guidance and our current Thailand laws guide. The earlier reference to a 2018 general election has been removed from this timeline.
History is not a clinical recommendation
Historical use can explain why a plant is culturally important and why researchers study it. It does not establish that a present product cures the conditions mentioned in an old text. Clinical questions require the actual preparation, relevant patients, measured outcomes and harms.
When reading a claim, ask which kind of source supports it: archaeology, a historical text, a legal instrument or a clinical study. That simple distinction prevents a centuries-old anecdote from being mistaken for evidence that someone should change treatment today.
Revised 6 September 2026. The timeline now distinguishes primary evidence, historical practice and present rules. Unsupported statistics, alleged ancient cures and inaccurate chronology have been removed.
