Short answer
Start with 2.5 mg to 5 mg of THC equivalent. THCA by itself does not produce a high. Heat drives a reaction called decarboxylation. It removes a carboxyl group and turns THCA into THC. One gram of THCA yields a maximum of about 0.877 g of THC, based on the molecular weights of both compounds. A label that lists 25 mg THCA per gummy does not mean 25 mg of active THC.
Dose ranges by tolerance
- New user: 2.5 mg THC equivalent or less.
- Occasional user: 2.5 mg to 10 mg.
- Daily user: 10 mg to 30 mg.
- Heavy user: 30 mg and above.
These ranges come from published reviews of oral THC products, not from controlled trials of THCA. No federal agency sets a standard dose for cannabis.
Route sets the timeline
Inhaled THCA converts to THC at the coil. Effects start in 5 to 15 minutes, peak at 15 to 30 minutes, and fade in 2 to 4 hours. Bioavailability runs 10% to 35%.
Oral THCA passes through the liver. Effects start in 30 to 120 minutes, peak at 2 to 4 hours, and fade in 4 to 8 hours. Bioavailability runs 5% to 20%. Wait two hours before a second dose.
Whether swallowed THCA converts to THC inside the body is not established. Most oral numbers above come from THC studies.
The 0.877 factor
THCA molecular weight: 358.5 g/mol. THC molecular weight: 314.5 g/mol. Divide 314.5 by 358.5 and you get 0.877. Multiply the THCA figure on a lab report by 0.877 to get the ceiling for THC after full decarboxylation. Real batches land below that ceiling. Home decarboxylation runs 220 F to 240 F for 30 to 60 minutes.
Convenience and dose control
Single-serve formats moved the dose decision to the factory. A 5 mg gummy, a 10 mg sachet, and a dropper marked in 1 mg steps remove the need for a scale. That helps a new user. It also hides the conversion math. A gummy labeled 50 mg THCA delivers a maximum of about 44 mg THC after decarboxylation. A buyer who reads the large number on the front gets a different dose than expected.
Federal rules
The 2018 Farm Bill caps hemp at 0.3% delta-9 THC by dry weight. The text names delta-9 THC, not THCA. Agencies and courts have split on whether THCA counts toward that cap. Check state law before you buy.
When to stop
Stop and seek medical help for chest pain, a heart rate above 150 beats per minute, or severe confusion. In the US, Poison Control answers at 1-800-222-1222. THC and THCA can impair driving.