Edibles Dosing: Why Onset Takes Longer and How Labeling Works

The most common edibles story goes like this: someone eats a gummy, feels nothing after 45 minutes, eats another, and an hour later feels far more than they wanted. The problem is not a bad product. It is timing. THC that you swallow takes a slower, different route through the body than THC you inhale, and the effects arrive later and last longer.

This explainer covers why that happens, what official sources say about onset and duration, how serving and package labels work in major markets, and what to do if a child or pet gets into edibles.

Why do edibles take longer to kick in? First-pass metabolism and 11-OH-THC

Swallowed THC must pass through the gut and liver before it reaches the rest of the body. When you inhale cannabis, THC is absorbed through the lungs. When you eat it, THC has to be absorbed through the gut and then pass through the liver, a step called first-pass metabolism. A review of human cannabinoid pharmacokinetics by Marilyn Huestis, published in 2007, summarizes what this means in numbers:

• Slower peak: across studies, peak THC levels in blood occurred roughly 1 to 5 hours after swallowing, and around 4 to 6 hours in one study using 15 to 20 mg doses.
• Lower and less predictable absorption: estimates of oral bioavailability vary; one careful study put it at about 6%.
• A second active compound: during that first pass through the liver, a significant share of THC is converted to 11-hydroxy-THC (11-OH-THC), which the review describes as equipotent to THC.

That last point is the one that makes edibles feel different. Because 11-OH-THC is active too, eating cannabis is not simply a slower version of smoking the same amount.

Onset and duration: 30 minutes to 2 hours to start, up to 24 hours to wear off

Exact timing varies with the person, the product and what else is in your stomach. These are the ranges published by health agencies and regulators we checked:

Serving sizes and package limits: 10 mg per serving in the U.S., 10 mg per package in Canada

Regulated edibles are labeled in milligrams of THC, usually both per serving and per package. The limits are set by each jurisdiction:

The comparison is striking. An entire legal package of edibles in Canada holds the same 10 mg of THC as a single serving in California, Colorado or Washington, where one package can hold ten servings. If you travel or buy products from different markets, check the milligrams rather than assuming that "one gummy" means the same thing everywhere. Our Canada, California and Colorado guides cover the local rules in more detail.

How to read an edible label, in order

• THC per serving — the dose in one piece or one marked portion.
• Servings per package — a 100 mg chocolate bar split into ten squares is ten 10 mg servings, not one snack.
• Total THC per package — the number that matters if a child or pet gets into it.
• Other cannabinoids — CBD or minor cannabinoids, if listed.
• Batch number — so you can match the product to its lab report. Our methodology explains why we value sellers that publish these.

A cautious approach: less than one 10 mg serving, then wait 90 minutes

Colorado's state cannabis site gives the clearest practical guidance we found. If you aren't sure how cannabis will affect you, it advises taking less than one 10 mg serving and waiting at least 90 minutes, and up to four hours, before eating or drinking more. It also notes that a single 10 mg serving will likely affect your ability to drive, bike or do other activities, especially for occasional consumers.

1. Check the label first
   Know the milligrams per serving and how the product is divided before you take a bite.
2. Take less than you think you need
   Colorado's advice is less than one 10 mg serving if you are unsure how it will affect you.
3. Wait, and set a timer
   At least 90 minutes before considering more; full effects can take up to four hours.
4. Plan for the long tail
   Don't drive, and don't plan anything that needs a clear head for the rest of the day. Health Canada says effects can last up to 24 hours.
5. Store the rest safely
   Locked, out of sight and reach of children and pets, and separate from regular food.

Children, pets and accidental ingestion: exposures rose from 207 to 3,054 a year

Edibles look like food, and that is the core of the risk for children. A study in the journal Pediatrics analyzed U.S. poison center data for children under 6 who were exposed to edible cannabis.

The study counted 7,043 exposures over five years, and 70% of cases followed to a known outcome involved central nervous system depression.

Hemp-derived products are part of the picture too, according to the FDA:

Reported symptoms included hallucinations, vomiting, tremor, anxiety, dizziness, confusion and loss of consciousness.

Signs of cannabis poisoning in children

Health Canada lists these signs, and notes that most cases in kids under 12 occur in children under 5:

• vomiting, confusion, unresponsiveness;
• slurred speech, unsteadiness on the feet;
• drowsiness or lethargy, slowed breathing;
• in rare cases, seizures.

Keep edibles away from pets as well. If an animal eats one, call your veterinarian or an emergency animal clinic right away and have the package at hand.

When to get medical help for yourself or a friend

Get medical help right away if someone who has taken too much has any of these:

• Chest pain — or trouble breathing.
• A seizure — call emergency services.
• Can't stay awake or be woken — do not wait it out.
• Severe confusion — especially if it is getting worse.

In the U.S. and Canada, poison centers can also advise adults on what to do; the numbers above work for any age. Don't let the person drive, and don't leave them alone while effects are strong.

This article is for general information and is not a substitute for professional medical advice.