Cannabis edible safety: short answer
Start low and wait. A standard serving in states with legal adult-use cannabis is 10 mg THC. Adults with no tolerance should start at 2.5 mg or less and wait at least 2 hours before a second dose. Effects begin in 30 minutes to 2 hours, peak at 2 to 4 hours, and can last 6 to 12 hours. Store edibles in a locked container away from children and pets.
Why edibles hit harder than smoked cannabis
Smoked THC reaches the bloodstream in minutes. Edible THC passes through the liver, which converts delta-9 THC into 11-hydroxy-THC. That metabolite binds to CB1 receptors with more strength and crosses into the brain. The result is a slower onset, a longer high, and a sharper rise in heart rate. A person who eats 30 mg often feels nothing at 30 minutes, takes more, and then absorbs both doses at once.
Dose ranges and state caps
- 2.5 mg THC: starting dose for a first-time user
- 5 mg THC: moderate dose for an adult with no recent use
- 10 mg THC: standard single serving in legal markets
- 25 mg and above: high risk of vomiting, panic, and rapid pulse in users without tolerance
Colorado, Washington, California, and other legal states cap retail servings at 10 mg THC and packages at 100 mg THC. A single chocolate bar can hold 10 servings. Read the label for total THC, not just THC per piece.
Timeline of effects
- 0 to 30 minutes: little or no effect
- 30 minutes to 2 hours: onset, relaxation, altered time sense
- 2 to 4 hours: peak concentration and peak impairment
- 4 to 12 hours: decline, with fatigue and dry mouth
Do not drive or operate machinery for at least 6 hours after a dose. Impairment can outlast the felt high.
Signs of too much THC
- Nausea and repeated vomiting
- Panic, paranoia, or confusion
- Heart rate above 120 beats per minute
- Unsteady walk, slurred speech
- Chest pain, seizure, or loss of consciousness
Most cases resolve with time, rest, and fluids. Call 911 for chest pain, a seizure, trouble breathing, or a person who will not wake. Call Poison Control at 1-800-222-1222 for advice on any suspected overdose. The line is free and open 24 hours.
Children and pets
Edibles look like candy, cookies, and gummies. Calls to US poison centers about young children and cannabis edibles rose after 2017. A 10 mg to 20 mg dose can cause drowsiness, vomiting, and trouble walking in a child who weighs 20 kg. Keep packages out of reach and treat them the same as prescription pills.
CBD edibles and lab testing
CBD isolate contains no THC. Full-spectrum CBD oil can contain THC at 0.3% or less by dry weight, and several servings can add up. Buy from sellers who post a certificate of analysis (COA) from an ISO 17025 lab with THC content per batch. CBD side effects include drowsiness, diarrhea, and changes in liver enzymes. CBD can raise blood levels of warfarin, clobazam, and some other drugs. The FDA has not approved CBD as a food ingredient or dietary supplement. The only FDA-approved CBD drug is Epidiolex.
Rules that cut risk
- Buy from licensed stores or sellers with third-party lab results
- Note the mg of THC on the package before the first bite
- Cut the edible into measured pieces
- Wait 2 hours between doses
- Do not mix with alcohol or sedatives
- Lock storage