What Does "Greening Out" Mean? Signs, Symptoms, and What to Do

Greening out is a common term used to describe feeling sick after consuming too much cannabis, especially products high in THC. While the experience can be frightening, it is usually temporary and improves with rest and time.

Symptoms often include dizziness, nausea, vomiting, sweating, anxiety, a racing heart, confusion, and feeling disconnected from reality. Some people become pale or extremely tired, while others experience intense panic and believe something is seriously wrong.

Modern cannabis products are much stronger than they were years ago. High potency flower, vape cartridges, concentrates, and edibles all increase the chance of consuming more THC than your body can comfortably tolerate. Edibles are especially unpredictable because the effects may not peak for several hours, leading some people to take more before the first dose has fully taken effect.

If you think you are greening out, stop using cannabis. Find a quiet place to sit or lie down, drink water if you are able, and focus on slow breathing. Having a trusted friend nearby can also help reduce anxiety while the effects wear off.

Most people recover without medical treatment. However, chest pain, trouble breathing, seizures, loss of consciousness, or severe confusion should never be ignored. Seek emergency medical care right away if those symptoms occur.

Why Does It Happen?

Greening out usually happens when someone consumes more THC than their body can tolerate. The risk is higher for people who are new to cannabis, use high potency products, combine cannabis with alcohol or other drugs, or take multiple edible doses too quickly.

How Long Does It Last?

After smoking or vaping, symptoms often improve within a few hours.

Edibles can last much longer, with some people feeling the effects for six to twelve hours or more.

When Should You Ask for Help?

One episode of greening out does not mean someone has a substance use problem.

If cannabis use becomes frequent, causes repeated episodes, affects work, school, relationships, or is being used to cope with anxiety or depression, it may be time to speak with a healthcare professional or learn more about residential mental health treatment. Addressing the underlying reason for using cannabis is often just as important as addressing the cannabis use itself.

At a Glance

What is greening out?
A temporary reaction to consuming too much THC.

Common symptoms
Dizziness, nausea, vomiting, sweating, anxiety, rapid heartbeat, confusion, and extreme fatigue.

How long does it last?
Usually a few hours after smoking or vaping. Edibles may last six to twelve hours or longer.

When should you seek emergency care?
Seek immediate medical attention for chest pain, difficulty breathing, seizures, loss of consciousness, or severe confusion.