Australian doctors are prescribing medical cannabis products that are much stronger than anything scientists have actually studied, according to a Guardian Australia report published July 29, 2026 (The Guardian). The findings come from a research review by scientists at Monash University, published in the journal Drug and Alcohol Review.

To understand the issue, it helps to know two things. THC is the main active ingredient in cannabis — the part that affects the mind. The TGA (Therapeutic Goods Administration) is Australia's government agency that checks whether medicines are safe and work properly. The TGA sorts medical cannabis products into categories, and Category 5 covers the strongest ones.

The research team, led by author M Graham and Professor Suzanne Nielsen, looked at 15 studies from around the world. The strongest THC level in any of those studies was 22%. In other words, the best available science only covers cannabis products up to that strength. But Category 5 products in Australia range from 13% to 88% THC — and there is no legal upper limit. The review found no evidence about whether products stronger than 22% are safe or effective.

Here is the other striking part: of more than 1,000 medical cannabis products sold in Australia, only two have gone through the TGA's full safety and quality check. The TGA's own website says most of these products are "unapproved," meaning they have not passed the same testing the agency normally requires before a medicine reaches patients. Since February 2021, the TGA has allowed pharmacy shelf sales of registered low-dose CBD products (a non-intoxicating cannabis compound), but that is a very different category from the high-THC products now in question.

Most prescriptions are for chronic pain and anxiety, according to TGA data reported by The Guardian. Category 5 products account for half of all approvals. A TGA spokesperson said 27 bad reactions to medical cannabis were voluntarily reported in the first half of 2026 alone. A separate study of 614 adverse event reports filed between mid-2022 and mid-2025, published in the Australian & New Zealand Journal of Psychiatry, found that half involved psychiatric or nervous system problems.

Professor Nielsen suggested the TGA set a THC limit at either 35% (the level that occurs naturally in the cannabis plant) or 22% (the level that has actually been tested). Her research centre made a formal written recommendation to the TGA in October 2025. The TGA had already announced in August 2025 that it planned to consult the public about safety concerns around these unapproved products.

Medical cannabis is on the TGA's list of priority issues for 2026, along with vapes, weight-loss drugs, and cosmetic procedures. The voluntary reporting system that logged those 27 cases likely catches only a small share of actual problems, given how many people are taking Category 5 products.

The broader context here is that Australia's system was built to give patients access to treatments they need, even when those treatments have not gone through full testing. That system is now handling a much larger and much stronger range of products than the evidence supports. Only two out of more than 1,000 products have faced the TGA's most thorough review. The gap between what patients are receiving and what science has studied is wider for cannabis than for most other medicines — because of how fast the patient base has grown, how strong the products have become, and how far behind the research has stayed.

Nielsen's two suggested limits give the TGA clear options: cap THC at the level science has tested (22%), or at the level the plant naturally produces (35%). Whatever the agency decides — adopt one of those numbers, pick its own, or do nothing — will shape how Australia handles the balance between giving patients access to treatment and making sure that treatment is safe. The TGA's planned consultation and its priority listing for 2026 show it is paying attention, but no new rules have been issued yet.