What is the difference between THCA and THC?

THCA (tetrahydrocannabinolic acid) is the acidic form of THC that the cannabis plant actually produces. Delta-9 THC is the neutral form. The two molecules differ by one carboxyl group. When THCA is heated enough, it loses that group as carbon dioxide and becomes delta-9 THC, a reaction called decarboxylation.

Why does my flower label show more THCA than THC?

Fresh, unheated flower holds most of its THC content as THCA, so lab tests report a large THCA number and a small delta-9 THC number. Many labels also show Total THC, which estimates how much delta-9 THC the product could contain if all the THCA were converted.

How is Total THC calculated?

The standard formula is Total THC = delta-9 THC + (THCA x 0.877). The 0.877 factor accounts for the weight of the carboxyl group that is lost during decarboxylation. For example, 24.0% THCA and 0.6% delta-9 THC works out to about 21.6% Total THC.

Is THCA flower from a DC dispensary different from hemp THCA flower sold online?

The THCA molecule is the same. The difference is the regulatory path. Products sold at an ABCA-licensed DC dispensary come from licensed cultivators and are tested under DC's medical cannabis rules, which require labs to report THCA, delta-9 THC, CBDA, CBD, and CBN along with contaminant screening.

Does DC regulate THCA?

Yes. DC's testing rules for medical cannabis, 22-C DCMR 6502.3, require licensed labs to measure THCA alongside delta-9 THC, CBDA, CBD, and CBN for each batch, and the results are uploaded to the District's tracking system.

THCA vs THC: What the Numbers on a DC Cannabis Label Mean

THCA vs THC explained for DC medical cannabis patients: the chemistry, decarboxylation, and how to read Total THC on a flower label. 21+.