Ask Dr. Leigh: What are the health benefits of THCA?


Using cannabis can have a big impact on your physical and mental health—for better, and sometimes for worse. That’s why it’s important to consult a healthcare provider before experimenting.

Here at GreenState, cannabis clinician Dr. Leigh Vinocur is here to answer your questions on healthy living with cannabis.

Editor’s Note: The answer to this question is meant to supplement, not replace, advice, diagnoses, and treatment from a healthcare provider.  Always consult a medical professional when using cannabis for medicinal purposes, and do not disregard the advice of your healthcare provider because of anything you may read in this article. 

Q: What is Tetrahydrocannabinolic acid (THCA)? And what are the health benefits of it?

A: Tetrahydrocannabinolic acid (THCA or THCa) is THC’s acidic precursor cannabinoid molecule, meaning that THC is derived from THCA. It is found in fresh, live plants and flowers. It is biosynthesized via the enzyme THCA synthase in the glandular trichomes of leaves and flowers from the compound cannabigerolic acid (CBGA). It represents up to 90% of the total plant THC. After drying, aging, light exposure or heating, it decarboxylates to its neutral non-acidic form, THC.

THCA is a secondary metabolite made by the plant to defend itself against predators, such as insects. It has garnered recent clinical therapeutic and scientific interest; however, the research is still relatively in its infancy. Additionally, pharmacological studies may be hampered because, in this acid form, it is very unstable, and it often degrades to THC.

We know that during smoking, 30% to 70% of  THCA converts to THC at temperatures over 140°C. As far as oral administration of THCA, since it is acidic, it is more water-soluble than THC and several studies have found it to have better oral absorption than THC.

THCA is non-intoxicating and not psychoactive. In part, because it is believed to have less binding at the CB1 or CB2 receptors, due to its increased water solubility which less readily diffuses across the blood-brain barrier. However, regardless of its cannabinoid receptor activity, there are other areas and receptors in the body that respond to THCA. These give THCA anti-inflammatory properties, as well as helping to protect your nervous system called neuroprotective properties, and even some studies that found THCA may have anti-cancer properties also called antineoplastic properties.

At the present, as it is with all cannabinoids in general, there aren’t a lot of human clinical trials defining clear-cut medical indications for THCA. However, there is promising preliminary preclinical research done in the lab, along with anecdotal evidence from clinicians that have advocated for its use for various medical conditions.

For example, because of its anti-inflammatory properties, it has been tried in arthritis and lupus. It has been advocated for use in neurodegenerative diseases and seizures as a neuroprotective agent with several studies using a Parkinson’s disease model and a Huntington’s model. It was also found to have anti-cancer properties in tissue cultures in the lab when looking at prostate cancer and breast cancer cells.

In conclusion, while THCA is not psychoactive, it certainly is not an inactive cannabinoid. It has demonstrated many interactions in the body that will require further human research for clinical effectiveness.

Additionally, more studies need to be done to also see why THCA has restricted access across the blood-brain barrier. However, this very aspect of its non-intoxicating effects may in fact be one of its main desirable traits, to pursue and maximize therapeutic use for many medical treatments without the high.

Got cannabis questions? Ask Doctor Leigh. Send your questions to GreenState’s Editor at and keep an eye out for new answers from Dr. Leigh Vinocur every month.

Dr. Leigh Vinocur is a board-certified emergency physician who also has a cannabis consulting practice for patients and industry. She is a member of the Society of Cannabis Clinicians and a graduate of the inaugural class, with the first Master of Science in the country in Medical Cannabis Science and Therapeutics from the University of Maryland School of Pharmacy.

The response to this question was not written or edited by Hearst. The authors are solely responsible for the content.

Leigh Vinocur, MD