Cannabis in Japan

02 Oct Cannabis in Japan

Posted at 15:22h in Blog, Top Blogs by Sean Karl 0 Comments

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Introduction

Cannabis has been cultivated in Japan for thousands of years. Ancient farmers grew hemp for fiber, clothing and rope; its seeds were eaten and the plant was used in religious rituals. Japan’s legal framework, however, historically prohibited the psychoactive parts of cannabis, and possession of cannabis has been a crime since just after World War II. Recently the law has undergone a major transformation that narrows the prohibition to high‑THC products, introduces strict THC‑residue limits, creates a pathway for medical cannabis and imposes new penalties for cannabis use. This report summarises the social history, regulatory changes and the current and future outlook for cannabis and hemp in Japan. It also examines the Good Manufacturing Practice (GMP) standards for cannabis‑derived pharmaceuticals and identifies the government agencies involved.

Social history and cultural context

Early cultivation and ritual uses of cannabis in Japan

Archaeological evidence suggests that cannabis (particularly hemp) has been cultivated in Japan since the Jōmon period (circa 10 000 BCE – 300 BCE). Hemp fibers were used to make cords, nets and clothing and were important in early agriculture. By the 8th century, hemp had become a vital agricultural product; seeds and oils were consumed, and hemp fibers were used to make ropes, fishing lines and textiles. Traditional Shinto rites employed hemp and cannabis seeds; hemp ropes symbolising purity are still used at shrines and sumo wrestling ceremonies. Historically the crop was not grown for its psychoactive properties; Japanese landraces contained very low levels of tetrahydrocannabinol (THC).

Cannabis in Edo to early twentieth century

During the Edo (Tokugawa) period (1603‑1868), hemp cultivation spread widely. Government surveys recorded thousands of hectares planted in what is now Tochigi, Gunma and Hokkaido. Farmers paid taxes in hemp fiber, and cannabis fibres were used to make uniforms for the military. Some historical sources suggest that psychoactive use of cannabis occurred in rural areas, especially among the Ainu and some communities, but such use was not widespread and remains debated.

Suppression and prohibition after World War II

Under the US‑led occupation after World War II, the Allied authorities and Japanese government adopted the Cannabis Control Act (CCA) in 1948. The law aimed to align Japan with the international drug‑control framework and to suppress recreational use. It distinguished cannabis by plant parts: seed and mature stalks were exempted because they were essential for hemp fibre and food, while leaves, flowers and roots and products derived from them were prohibited. As a result, hemp cultivation dramatically declined; by 2016 only 37 farms were licensed.

Legal framework: past to present

Pre‑2024 regulation

Cannabis Control Act (CCA) 1948 – prohibited cultivation, import/export, sale and research of cannabis leaves and flowers without a licence. Separate “cannabis handler” licences allowed farmers to grow hemp with THC‑free seeds and stalks. Possession and trafficking of cannabis were punishable by up to 10 years’ imprisonment and fines, but use itself was not a crime; this loophole was unique among Japanese drug laws.
Narcotics and Psychotropics Control Act (NPSCL) – governed narcotics such as morphine and cocaine, but cannabis was excluded, meaning that cannabis was regulated separately under the CCA.
UN Conventions – Japan ratified the Single Convention on Narcotic Drugs and other UN treaties. Despite global debate, Japan opposed the 2020 UN vote to remove cannabis from Schedule IV, arguing that medical evidence was insufficient and deregulation could harm public health.
Licence categories – cultivators required licences issued by prefectural governors. Industrial hemp cultivation used low‑THC strains such as Tochigishiro (≤0.2 % THC). Researchers could obtain research licences, but clinical trials of cannabis‑derived medicines could not lead to marketing approval under the CCA.

The 2023–2024 amendments

In response to rising cannabis use (6 462 cannabis criminal cases in 2023 surpassed methamphetamine cases) and pressure from patients needing cannabinoid medicines, the Japanese Diet enacted landmark amendments on 6 December 2023. Key elements include:

Medical cannabis pathway – The CCA’s blanket ban on cannabis medicines was removed; cannabinoids such as CBD and even THC can be approved as pharmaceuticals once they meet the safety, efficacy and quality requirements of the Pharmaceutical and Medical Device (PMD) Act. The change is expected to enable the approval of Epidiolex (a CBD oral solution for severe epilepsy), which had started a phase III trial in Japan.
Criminalization of cannabis use – A new offence was introduced: use (施用) of cannabis is now punishable with up to 7 years’ imprisonment under the NPSCL. Previously only possession or trafficking were punished.
Transfer of regulation – Cannabis and products containing THC are now designated as narcotics and regulated under the NPSCL; the CCA has been renamed the Act on Regulation of Cannabis Cultivation. Innocuous cannabinoids like CBD are excluded and treated like regular pharmaceuticals.
Tiered licensing system – Two licence categories have been established:
- Type 1 licence – For cultivation of low‑THC hemp (≤0.3 % Δ9‑THC on a dry‑weight basis) for industrial use. Issued by prefectural governors, this licence allows farmers to grow hemp for fibre, food and other non‑medical uses. Seeds must be from approved varieties with THC concentrations below the standard value.
- Type 2 licence – For cultivating cannabis plants intended as raw materials for medicinal products regardless of THC content. Issued by the Minister of Health, Labour and Welfare (MHLW), this licence opens a pathway for domestic production of medical cannabis.
THC residue limits – The amendments introduced residue thresholds for Δ9‑THC in consumer products. According to MHLW guidance, products containing THC above 10 ppm for oils and powders, 1 ppm for edibles and cosmetics, and 0.10 ppm for aqueous solutions are classified as narcotics and subject to strict control. Products exceeding the limits must be destroyed, and importers risk public disclosure and recalls.
Implementation stages – Stage 1 of the amended law took effect on 12 December 2024, enforcing the use offence and residue limits. Stage 2 came into force on 1 March 2025, implementing the licensing system and THC testing protocols. Full implementation and further regulations are expected during 2025.

Present legal status of cannabis in Japan (2025)

Recreational use – Cannabis remains strictly prohibited for recreational purposes. Possession, cultivation and now use carry penalties of up to seven years imprisonment. Police and prosecutors actively enforce the law; the National Police Agency reported thousands of cannabis offences annually.
Medical cannabis – Clinical trials of CBD and THC products can proceed, and pharmaceutical companies can apply for approval once safety and efficacy are demonstrated. Patients with treatment‑resistant conditions may access approved cannabis medicines under medical supervision. However, the patient use of unapproved cannabis products remains illegal except under specific transitional exemptions for existing CBD preparations.
Hemp and CBD products – CBD products derived from stems and seeds and containing virtually no detectable THC remain legal. The newly imposed residue limits (10 ppm for oils, 1 ppm for edibles/cosmetics and 0.10 ppm for beverages) set one of the world’s strictest thresholds. Importers must provide certificates of manufacture and analysis from accredited labs; shipments with detectable THC are destroyed by customs.

Future developments and debates

Full implementation of ingredient‑based regulation – By 2025 Japan is transitioning from plant‑part‑based rules to an ingredient‑based regime. Residue standards will become the primary criteria for classifying cannabis products; ISO 17025‑accredited laboratory testing will be required and supply chain traceability must be documented. Enforcement at borders and retail will intensify, and failure to meet THC limits may lead to recalls or criminal liability.
Expansion of medical cannabis research – MHLW plans to expand research beyond epilepsy to conditions such as chronic pain and multiple sclerosis. Clinical trials must comply with the PMD Act and Good Clinical Practice standards, and any approved medicine will be regulated as a narcotic under the NPSCL. Despite the legal pathway, commentators note that Japan’s conservative attitude may limit the number of approved products.
International harmonization – Japan’s shift to ingredient‑based controls aligns with global trends and responds to UN treaty adjustments. However, the government continues to oppose broad legalization and emphasises deterrence for youth.

Good Manufacturing Practice (GMP) standards for cannabis‑derived pharmaceuticals

Cannabis‑derived pharmaceuticals approved in Japan will be subject to the same quality and manufacturing requirements as other drugs under the Pharmaceutical and Medical Device (PMD) Act. Key aspects include:

GMP compliance – Manufacturers must implement Good Manufacturing Practice systems covering facility design, equipment, personnel training, production controls and quality control. Japan harmonises its GMP with the Pharmaceutical Inspection Co‑operation Scheme (PIC/S); in 2014 Japan joined PIC/S, and its GMP enforcement notifications were revised to meet international standards. Compliance requires periodic inspections by MHLW/PMDA and documented procedures for each batch.
Clinical trial GMP – For investigational products, GMP ensures quality at each clinical trial stage; the 2008 revision of GMP for investigational drugs emphasises quality management for products used in clinical trials. Cannabis‑derived drugs undergoing trials must meet these standards.
Data package for approval – Applicants for cannabis‑derived medicines must submit comprehensive manufacturing and quality control data, including details of cultivation, extraction, purification and stability. They must also demonstrate compliance with Japanese GMP and show that the product consistently meets the ultra‑low THC specifications. Importers must hold narcotics handling licences for distribution.
Consumer CBD products – Though not pharmaceuticals, consumer CBD oils, edibles and cosmetics must still be manufactured under hygienic conditions. Because they cannot be marketed with therapeutic claims, they fall under food, cosmetic and supplement regulations; however, failure to meet THC limits can result in classification as a narcotic and enforcement under the NPSCL.

Government agencies and stakeholders

Agency/Stakeholder	Roles and Responsibilities
Ministry of Health, Labour and Welfare (MHLW)	Primary regulatory authority. Drafted and enforces the CCA and NPSCL amendments; sets THC residue limits; designates accredited testing laboratories; issues Type 2 cultivation licences; processes import/export permits via the Narcotics Control Department; approves clinical trials and marketing of cannabis‑derived medicines; oversees enforcement through regional health bureaus.
Narcotics Control Department (NCD) (part of MHLW’s Regional Bureaus of Health and Welfare)	Conducts investigations and enforcement of narcotics laws; issues import permits for regulated cannabis products; collects evidence of illegal use; coordinates with customs and police; provides guidance for importers.
Prefectural Governors	Issue Type 1 licences for cultivation of low‑THC hemp. Oversee compliance of licensed farms with seed sourcing and THC concentration requirements. Monitor local hemp cultivation and coordinate with the MHLW on enforcement.
Pharmaceuticals and Medical Devices Agency (PMDA)	Conducts reviews of safety, efficacy and quality data for cannabis‑derived pharmaceuticals; performs GMP inspections; recommends approval or rejection to the MHLW; monitors post‑marketing safety.
National Police Agency (NPA) and prefectural police	Enforce drug laws; investigate possession, trafficking and use; collect urine samples to prove the new offence of cannabis use; support education campaigns to prevent drug abuse.
Customs and Tariff Bureau (Ministry of Finance)	Inspects imported parcels and cargo. Requires importers of CBD products to present Import Permission from MHLW and certificates showing products are extracted from stalks or seeds; denies entry to goods without proper documentation. Seizes and destroys shipments containing THC above residue limits.
Diet (House of Representatives & House of Councillors)	Legislates cannabis policy. Passed the 2023 amendments enabling medical use and criminalizing consumption. Ongoing debate influences future reforms.
Liberal Democratic Party (LDP)	Governing party that proposed the 2023 amendment. The party’s policy paper emphasised enabling cannabis‑derived medicines, penalizing use, and revising cultivation regulations; it outlined the two‑tier licence system.
Patient advocacy groups	Organisations representing people with intractable epilepsy and other conditions campaigned for access to CBD medicines. Their activism was instrumental in prompting clinical trials and the 2023 amendments.

Outlook

Japan’s approach to cannabis is shifting from near‑total prohibition to a tightly controlled system that differentiates between industrial hemp, harmless cannabinoids like CBD, and psychoactive THC‑containing products. The new legal framework criminalizes cannabis use, imposes ultra‑low THC residue limits, and introduces a dual licensing system for hemp and medical cannabis cultivation. Importantly, it also opens a narrow pathway for cannabis‑derived pharmaceuticals, subject to stringent GMP and regulatory requirements. These reforms align Japan with international trends while preserving a conservative stance on recreational use. Businesses seeking to enter Japan’s emerging medical cannabis and CBD markets must navigate complex compliance obligations, maintain rigorous quality control and ensure traceability. For patients, the reforms offer hope for access to approved cannabis medicines, but practical availability will depend on successful clinical trials and cautious regulatory approvals over the coming years.

References

Cannabis in Japan – Wikipedia

https://en.wikipedia.org/wiki/Cannabis_in_Japan

Cannabis-Derived Drugs in Japan: New Legislation and Outlook

https://globalforum.diaglobal.org/issue/february-2025/cannabis-derived-drugs-in-japan-new-legislation-and-outlook/

What Travelers Need to Know About Drug Laws in Japan

https://www.worldnomads.com/travel-safety/eastern-asia/japan/japan-drug-laws-the-zero-tolerance-approach

Understanding-Japans-Cannabis-Law-Reforms_MP_fin.pdf

https://mps-legal.com/en/wp-content/uploads/sites/2/2025/08/Understanding-Japans-Cannabis-Law-Reforms_MP_fin.pdf

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https://www.jimin.jp/news/information/206838.html

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