Cannabis overdose symptoms include anxiety, panic, rapid heartbeat, nausea, vomiting, confusion, and paranoia. A fatal cannabis overdose is rare, but high doses can cause severe distress and a trip to the emergency room. The risk rises with edibles, concentrates, and mixing cannabis with alcohol.
What Is a Cannabis Overdose?
A cannabis overdose means taking more THC than your body can handle. THC is the compound in marijuana that causes intoxication. Unlike opioids, THC does not stop breathing, so death from cannabis alone is very rare. However, the experience can feel overwhelming and lead to injury or panic.
Cannabis Overdose: What Actually Happens and What to Do
People use the term "overdose" to describe acute intoxication. The symptoms vary by dose, product strength, and how you consume it. Edibles and concentrates deliver large amounts of THC, often more than smoking.
Cannabis and Overdose Risk: What You Need to Know
Common Cannabis Overdose Symptoms
Most symptoms appear within minutes to a few hours. They can last for several hours, depending on the product.
Is It Possible to Overdose on Cannabis?
- Rapid heart rate or palpitations
- Dry mouth and red eyes
- Nausea and vomiting
- Dizziness and loss of coordination
- Anxiety, panic, or fear
- Paranoia or suspicious thoughts
- Confusion and disorientation
- Slow speech or trouble thinking
- Drowsiness or extreme fatigue
Symptoms differ by person. A dose that feels mild to one user can cause panic in another. Your tolerance, body weight, and metabolism all play a role.
Severe Symptoms That Need Emergency Care
Some people develop severe reactions that require medical help. Call 911 or go to an emergency room if you see these signs.
- Chest pain or pressure
- Seizures
- Severe agitation or violence
- Hallucinations or psychosis
- Fainting or unresponsiveness
- Slow, shallow breathing (rare, but possible with other drugs)
- Suicidal thoughts
These symptoms are more common in people with a history of mental illness or those who mix cannabis with other substances. Data from poison control centers show a rise in calls about cannabis, especially from edibles.
What Is Cannabinoid Hyperemesis Syndrome?
Some long-term cannabis users develop a condition called cannabinoid hyperemesis syndrome (CHS). It causes repeated, severe vomiting and abdominal pain. Hot showers or baths often relieve the symptoms. The only cure is stopping cannabis use.
Who Is at Higher Risk?
- First-time users or people who use cannabis rarely
- People who eat edibles without waiting for the full effect
- Users of high-THC concentrates like dabs or oils
- People who mix cannabis with alcohol or other drugs
- Those with a personal or family history of psychosis
- Teens and young adults whose brains are still developing
How Much THC Is Too Much?
There is no standard "safe" dose of THC. A typical smoked dose is 10 to 20 mg. A standard edible serving is 10 mg. Many people take far more by mistake. Products with 100 mg or more per package raise the risk of overdose symptoms.
Start with a low dose, especially with edibles. Wait at least two hours before taking more. This step prevents most overdoses.
Why Edibles Cause More Overdoses
Edibles pass through the liver and turn into a stronger form of THC. This effect makes the high more intense. The onset takes 30 to 90 minutes, so people eat more before the first dose hits. That delay leads to accidental overdose.
Cannabis Overdose vs. Opioid Overdose
Opioid overdose slows breathing and can kill. Naloxone reverses it. Cannabis overdose does not respond to naloxone. The two look different. A person with cannabis overdose is awake but panicked. A person with opioid overdose is sleepy and breathing slow. Call 911 for either.
What to Do If Someone Shows Symptoms
- Stay calm and reassure the person. Panic makes symptoms worse.
- Move them to a quiet, safe space with low lighting.
- Offer water to drink. Do not force food.
- Do not leave them alone. Watch for severe signs.
- Call 911 or Poison Control (1-800-222-1222) if symptoms are severe or get worse.
- Tell medical staff what they took, how much, and when.
Does CBD Cause an Overdose?
CBD does not cause intoxication and has no known lethal dose. A CBD overdose is not a recognized medical condition. Some people may feel drowsy or have an upset stomach after taking large amounts of CBD, but these effects are mild. CBD products with THC can cause overdose symptoms if the THC content is high.
Frequently Asked Questions
Can you die from a cannabis overdose?
Death from cannabis alone is very rare. No confirmed case exists of a fatal overdose from THC by itself. However, cannabis can cause accidents, injuries, and dangerous behavior that lead to death.
How long do cannabis overdose symptoms last?
Symptoms from smoked cannabis last 2 to 4 hours. Edible symptoms can last 6 to 12 hours or longer because the body processes THC slowly.
When should I go to the hospital?
Go to the hospital if you have chest pain, seizures, severe vomiting, hallucinations, or thoughts of self-harm. Also seek help if the person cannot stay awake or breathe well.
Is cannabis overdose the same as cannabis poisoning?
Yes, the terms overlap. Poison centers use "cannabis poisoning" for any harmful reaction to cannabis, including overdose symptoms.