Can Weed Kill You? Understanding the Real Risks

Hidden Dangers: Indirect Fatality Risks

Impaired Driving Deaths and Occupational Injury

The biggest risks come from how marijuana affects your judgment and reaction time. Driving while high significantly increases your chance of getting into a deadly accident.¹¹ The short-term effects of cannabis can last several hours, making it unsafe to drive even if you feel “okay.”

Research is still ongoing, but there’s also evidence of a link between marijuana and work-related injuries.¹¹

Drug Interactions

Mixing cannabis with alcohol or other drugs is especially dangerous. These combinations can lead to severe reactions your body can’t handle. They can also make you more likely to make risky decisions.

Marijuana and other drugs are commonly taken in combination with alcohol. While this is a common practice, its risks are more serious than most people realize. Learn more about this in our article on the dangers of combined alcohol and drug use.

Contaminated Products

When you buy marijuana from unlicensed sellers, you don’t really know what’s in it. There’s a real risk that these products could be mixed with harmful substances or contaminants.

What Happens During a Marijuana Overdose

“Contrary to popular belief, it is possible to overdose on cannabis,”¹² says Manitoba Health. “It is not fatal, but overconsumption can be very uncomfortable.” While a marijuana overdose won’t kill you directly, it can be a frightening experience. Sometimes, it requires medical attention. 

Signs of THC poisoning¹³ include: 

• Extreme anxiety or panic
• Racing heart
• Paranoid thoughts
• Severe nausea
• Mental confusion
• Hallucinations

Edible marijuana products pose special risks because they’re harder to dose correctly. The effects take longer to feel, which might make you think you need more. This often leads people to accidentally take too much.

Most of the time, you can just wait for the effects to wear off. If your symptoms are very severe or you have chest pain, panic attacks, or seizures, get medical help.

THC is never safe for children in any amount. If your child has consumed THC, contact the Poison Control Center hotline at 1-800-222-1222.

High-Risk Situations and Populations

Certain risk factors put some people at higher risk of health complications when they use marijuana. 

• People with heart conditions or high blood pressure should be especially careful. Marijuana can make these conditions worse.
• Young people under 25 face unique risks because their brains are still developing. Regular marijuana use during teen and young adult years¹⁴ can affect memory, learning, and mental health.
• People with a personal or family history of mental health conditions like anxiety, depression, or psychosis should be cautious. Marijuana can make these conditions worse or trigger new symptoms.
• Pregnant people should avoid marijuana. It can affect the developing baby and lead to health problems.

Making Informed Decisions

If you choose to use marijuana, there are ways to reduce your risks:¹³

• Read the labels on your products and understand the dose you’re taking.
• Start with a very small amount, especially with edibles. Wait at least 2 hours before taking more.
• Never drive after using marijuana. Plan ahead for safe transportation.
• Don’t mix marijuana with alcohol or other drugs.
• Keep cannabis products locked away from children and pets.
• Avoid synthetic cannabinoids, which are known to cause adverse effects. The effects of these products are not at all like the effects of marijuana.

The CDC also advises against vaping marijuana:¹⁵

Oils and concentrates used in vaping and dabbing (which is a specific method of inhaling THC concentrates) often have highly concentrated forms of THC and may contain additives or be contaminated with other substances. The effects of using these more concentrated forms of THC are not well understood but may include higher risk of developing cannabis use disorder. Vaping has also been linked to lung injury.

Changing Attitudes Toward Marijuana Use

As recreational and medical marijuana becomes more widely accepted in many places, people tend to view it as harmless. While it’s true that marijuana is less dangerous than many other kinds of substance use, this shifting attitude has led some people to overlook its very real risks. 

These days, fewer teens believe marijuana is dangerous.¹⁶ This is a real concern, since research clearly shows that using marijuana heavily during the teenage years can get in the way of healthy development and daily functioning.

When to Get Help

Sometimes marijuana use can become a problem. If you’re using more than you planned to, feeling unable to cut back or stop, neglecting responsibilities at work or school, or continuing to use despite negative effects on your health or relationships, it could be a sign of marijuana addiction.

If you notice these signs or feel worried about your use of marijuana, talking to your therapist or primary care provider is a great place to start. They can help you understand your options and find support to make the changes you want. If you’re looking to quit using marijuana in an immersive, substance-free setting, residential rehab can be a great place to start your healing journey. Search for a marijuana addiction treatment program that meets your needs and reach out to a support specialist today.

Frequently Asked Questions About the Health Risks of Marijuana 

Can you overdose on marijuana?

Contrary to popular belief, it is possible to overdose on cannabis. While such overdoses aren’t fatal like with alcohol or opioids, overconsumption can be very uncomfortable. In some cases, taking too much marijuana—especially via edibles—can cause severe reactions like temporary catatonia or even acute psychosis.

Can marijuana use lead to death?

While marijuana doesn’t cause direct fatal overdoses, it can lead to death through indirect means. In one documented case from Colorado, a man died after consuming a cannabis cookie and jumping from a fourth-floor balcony. Excessive marijuana use can cause erratic behavior that may lead to accidents or risky decisions.

What are the long-term health risks of marijuana use?

The long-term effects of marijuana use can include several serious health problems. Smoking marijuana can damage your lungs, leading to bronchitis, emphysema, asthma, and it increases the risk of head, neck, throat, and lung cancers. Regular use can weaken your immune system and increase your risk of developing mental health issues later in life. Young people are especially vulnerable to these side effects.