What's the deal with THCA?

Every once in a while, a patient calls us concerned that their medical marijuana product label indicates a different amount of the THC cannabinoid than what they read on our menus. In most cases, they are actually reading the THCA percentage on the label, which is different from THC.

Think of THCA as the precursor to THC. All THC starts as THCA, a non-psychoactive cannabinoid found in raw cannabis plant materials. In order to fully convert THCA to THC, heat must be applied. This is why you can’t just eat dry leaf and expect psychoactivity. 

Once you vaporize your dry leaf, live resin cartridge, or concentrate to around 220°F, a process called decarboxylation occurs. The carboxylic acid group is removed and released as CO2 and water vapor, and the THCA becomes THC. 

But not all the THCA gets converted to THC. The generally accepted conversion rate, and what our team calculates before entering all cannabinoid data into our menu, is 87.7%

For the math lovers out there, here’s the equation broken down: 

Total Potential THC = (0.877 * %THCA) + %THC

For example, the Stardawg Guava  dry leaf that we have now tests at 22.54% THCA and 0% THC. Once heat is applied, patients will net 87.7% of that THCA as THC, equaling 19.77%. We put the net THC on the menu so patients don’t have to do the math. 

Distillate cartridges, capsules, tinctures, RSO, and distillate syringes contain already activated THCA, because the Grower/Processor has used heat in their extraction and processing. The labels on these products will reflect the accurate percentage of THC without any additional math required.

If you have more questions about this or any other medical marijuana topic, call your preferred location at 412.404.7464 in Pittsburgh or 724.550.4565 in Uniontown and ask to speak with a Pharmacist.