Synthetic marijuana, commonly called K2 or Spice, refers to a group of laboratory-made chemicals known as synthetic cannabinoids. These substances are designed to produce effects that resemble THC, the main psychoactive component of cannabis, but they are not the same as marijuana. Their chemical contents can vary substantially, making their effects difficult to predict.[2][4]
K2/Spice can cause agitation, confusion, hallucinations, rapid heart rate, vomiting, high blood pressure, seizures and other serious reactions. Severe symptoms can require emergency medical care.[1][2]
The term synthetic marijuana can be misleading. K2 and Spice are not manufactured versions of cannabis. They are names used for various synthetic cannabinoids, which are man-made chemicals that interact with cannabinoid receptors in the body.[2][4]
Some products have been sold as dried plant material sprayed with chemicals, while others have been sold as liquids. Labels may describe products as incense or natural substances, but those descriptions do not establish what chemicals the product actually contains.[2][4]
The chemical composition of synthetic cannabinoid products can vary, which contributes to unpredictable effects.[1][2] CDC notes that the health effects of synthetic cannabinoids can be unpredictable because of their chemical contents.
When Is K2/Spice Use a Medical Emergency?
A serious reaction should not be managed by waiting for symptoms to resolve on their own. Call 911 or seek emergency medical care immediately if someone who has used K2/Spice has a seizure, trouble breathing, collapses, cannot be awakened, or develops severe agitation, confusion, or another rapidly worsening reaction. [1][3] CDC and Poison Control guidance emphasize emergency evaluation for serious synthetic cannabinoid reactions.
Because the specific substance involved may be unknown, treatment generally focuses on the person’s symptoms and any complications that develop. [1]
How Does K2/Spice Affect the Body?
Synthetic cannabinoids can affect several body systems at the same time.
- Brain and nervous system: Reported effects include agitation, confusion, dizziness, impaired coordination, delirium and seizures. Severe cases can involve loss of consciousness or other neurological complications.[1]
- Mental health: Hallucinations, paranoia, delusions, psychosis and severe behavioral changes have been reported following synthetic cannabinoid exposure.[1]
- Heart and circulation: Rapid heart rate, high blood pressure, chest pain, and other cardiovascular complications can occur. Severe poisoning can involve serious cardiovascular problems. [1][2]
- Digestive system: Nausea and vomiting are among the reported physical effects.[1]
What Are the Short-Term Effects of K2/Spice?
The short-term effects of K2/Spice can vary widely because different products may contain different synthetic cannabinoids and concentrations. Common reactions include anxiety, agitation, confusion, problems thinking clearly, hallucinations, paranoia, changes in heart rate or blood pressure, nausea, vomiting, dizziness, impaired coordination, and changes in alertness or consciousness.[1][2]
Some reactions can be more severe. K2/Spice exposure has been associated with psychotic-like behavior, severe agitation, disorganized thinking, seizures, chest pain, abnormal heart rhythms, loss of consciousness, and other neurological or cardiovascular complications.[1][2][3]
Symptoms can include:
- Anxiety, fear, or severe agitation
- Confusion or difficulty thinking clearly
- Hallucinations, paranoia, or delusional thinking
- Dizziness, impaired coordination, or changes in alertness
- Rapid or abnormal heart rate
- High blood pressure
- Nausea and vomiting
- Chest pain
- Seizures
- Difficulty breathing
- Loss of consciousness
Not everyone experiences the same effects. The specific synthetic cannabinoid, concentration, amount involved, route of exposure, and possible use of other substances can influence the reaction. Because K2/Spice products are not standardized, the product name or packaging cannot reliably indicate what chemicals or concentrations are present.[1][2]
What Are the Serious Health Risks of K2/Spice?
K2/Spice can cause severe poisoning that requires emergency medical treatment. Serious reactions may involve seizures, psychosis or dangerous behavioral changes, severe cardiovascular effects, acute kidney injury, loss of consciousness, coma, stroke, and, in some cases, death.[1][2][3]
Neurological and Mental Health Risks
Severe K2/Spice reactions can cause hallucinations, paranoia, delusions, disorganized thinking, severe agitation, psychosis, seizures, and changes in consciousness. In some cases, psychiatric or neurological effects may continue after the acute intoxication has passed.[1][2]
Cardiovascular Risks
Synthetic cannabinoids can raise heart rate and blood pressure and may cause abnormal heart rhythms or chest pain. Severe poisoning has also been associated with serious cardiovascular complications, including stroke and other potentially life-threatening events.[1][2][4]
Kidney Risks
Acute kidney injury has been reported following synthetic cannabinoid exposure and may occur alongside other serious complications. Suspected severe reactions require prompt medical evaluation.[1][2][4]
Other Serious Complications
Severe poisoning can also involve repeated vomiting, breathing problems, loss of consciousness, coma, and other complications. Because the chemicals and concentrations in illicit K2/Spice products can vary, the severity of one person’s previous reaction cannot reliably predict what will happen after another exposure.[1][2]
Can Someone Overdose on K2/Spice?
Yes. Severe poisoning from synthetic cannabinoids can occur, and some reactions have resulted in hospitalization or death. There is no dependable universal dose at which an overdose occurs because products can contain different chemicals and concentrations.[1][2][3]
A person experiencing a seizure, difficulty breathing, loss of consciousness or another severe reaction needs emergency medical attention rather than observation at home.[1][3]
Is K2/Spice Addictive?
Repeated synthetic cannabinoid use can lead to dependence. Some people who use synthetic cannabinoids regularly may experience withdrawal symptoms after stopping. Reported withdrawal symptoms can include anxiety, sweating, sleep problems, nausea, and vomiting. [1][2]
This does not mean every person who uses K2 will develop a substance use disorder. However, repeated use despite harmful consequences, difficulty stopping, cravings or withdrawal symptoms are reasons to seek a professional assessment.[1]
How Long Does K2 Stay in the Body?
There is no single reliable detection window for all K2 or Spice products. Synthetic cannabinoids represent a large and changing group of chemicals, and different compounds can behave differently in the body.
Another important distinction is drug testing. Standard marijuana screening tests may not detect many synthetic cannabinoids because these compounds may not reliably cross-react with traditional cannabis immunoassays. Whether a particular synthetic cannabinoid can be detected depends on the compound and the testing method used. [5]
What Should Someone Do After K2/Spice Exposure?
A person with severe symptoms should receive emergency medical care immediately.[1][3]. A person experiencing concerning symptoms while remaining conscious and breathing normally should receive medical or poison-control guidance rather than being assumed to recover without evaluation. Poison Control advises prompt assessment for symptoms associated with synthetic cannabinoid exposure.[3]
When medical care is needed, clinicians should be told what substance was reportedly used, when the exposure occurred, and what symptoms developed. If packaging or other product information is available, provide it to medical professionals rather than relying on the product’s marketing claims. [3]
How Is Synthetic Cannabinoid Use Treated?
Treatment for synthetic cannabinoid poisoning is generally supportive and focuses on managing symptoms, stabilizing the person, and treating complications that develop.[1][2]. For someone who repeatedly uses K2/Spice or has difficulty stopping, treatment can involve assessment for substance use disorder and co-occurring mental health concerns. The appropriate level of care depends on factors such as symptoms, safety, substance-use history and the person’s living environment.
Teen Treatment for K2/Spice Use
A teen who has experienced a serious K2/Spice reaction may need more than emergency medical care if synthetic cannabinoid use becomes repeated or difficult to control. After the immediate effects have been medically stabilized, an adolescent-focused assessment can help determine whether ongoing substance use, withdrawal symptoms, behavioral changes, or co-occurring mental health concerns require treatment.
A medical evaluation may also be appropriate when symptoms persist after the acute reaction, particularly when the substance involved is unknown or other substances may have been used.
Clearfork Academy provides behavioral health treatment for adolescents dealing with substance use and related mental health concerns. For teens whose K2/Spice use is recurring or affecting their behavior, relationships, school functioning, or daily life, treatment may include residential care, partial hospitalization (PHP), intensive outpatient (IOP), or virtual intensive outpatient care. The appropriate level of care depends on the teen’s symptoms, safety needs, substance-use history, and level of support required.
Treatment can address the factors contributing to repeated synthetic cannabinoid use while also providing support for co-occurring mental health concerns. Families can work with the treatment team to determine which level of care is appropriate after the teen has received any necessary medical evaluation for acute K2/Spice poisoning.
Frequently Asked Questions
Q. What should I do if I think my teen used K2/Spice?
If a teen has a seizure, trouble breathing, collapses, cannot be awakened, or develops severe or rapidly worsening symptoms, call 911 immediately. For concerning but non-emergency symptoms, seek medical or poison-control guidance rather than assuming the reaction will resolve on its own.
Q. How long do the effects of K2/Spice last?
There is no single reliable duration for K2/Spice effects because different synthetic cannabinoids can produce different reactions. The substance used, amount, route of exposure, and other substances involved can affect how long symptoms last. Severe or persistent symptoms should be medically evaluated rather than judged by an expected duration.
Q. Can K2/Spice cause psychosis?
Yes. Synthetic cannabinoid exposure can cause hallucinations, paranoia, delusions, severe agitation, and psychotic symptoms. Severe or rapidly worsening changes in behavior or awareness require urgent medical evaluation.
Q. Can K2/Spice cause kidney problems?
Yes. Acute kidney injury has been reported after synthetic cannabinoid exposure. Kidney complications can occur alongside other severe effects and may require hospital treatment.
Q. What happens after a teen is treated for K2/Spice poisoning?
After the immediate reaction is stabilized, healthcare professionals may assess for complications, other substances involved, and whether repeated synthetic cannabinoid use or related mental-health concerns require follow-up treatment.
Q. When does K2/Spice use require addiction treatment?
Professional treatment may be appropriate when a teen repeatedly uses K2/Spice, has difficulty stopping, continues using despite harmful consequences, experiences withdrawal symptoms, or develops problems involving school, relationships, behavior, or mental health.
Medical Disclaimer: This article is for informational purposes only and does not constitute medical advice, diagnosis, or treatment. Synthetic cannabinoid exposure can cause serious or life-threatening reactions. Seek medical care for concerning symptoms, and call 911 for an emergency.
References:
- Centers for Disease Control and Prevention (CDC). Cannabis Frequently Asked Questions: How harmful is K2/Spice (also called synthetic cannabinoids)?
CDC — Cannabis Frequently Asked Questions - U.S. Drug Enforcement Administration (DEA). K2/Spice, Synthetic Marijuana — Drug Fact Sheet. January 22, 2025.
DEA — K2/Spice, Synthetic Marijuana - Poison Control. Get help for a poisoning.
Poison Control — Get Help for a Poisoning - National Institute on Drug Abuse (NIDA). Mind Matters: K2/Spice and Bath Salts.
NIDA — Mind Matters: K2/Spice and Bath Salts - Arntson A, Ofsa B, Lancaster D, Simon JR, McMullin M, Logan B. Validation of a novel immunoassay for the detection of synthetic cannabinoids and metabolites in urine specimens. Journal of Analytical Toxicology. 2013.
Austin Davis, LPC-S
Founder & CEO
Originally from the Saginaw, Eagle Mountain area, Austin Davis earned a Bachelor of Science in Pastoral Ministry from Lee University in Cleveland, TN and a Master of Arts in Counseling from The Church of God Theological Seminary. He then went on to become a Licensed Professional Counselor-Supervisor in the State of Texas. Austin’s professional history includes both local church ministry and clinical counseling. At a young age, he began serving youth at the local church in various capacities which led to clinical training and education. Austin gained a vast knowledge of mental health disorders while working in state and public mental health hospitals. This is where he was exposed to almost every type of diagnosis and carries this experience into the daily treatment.
Austin’s longtime passion is Clearfork Academy, a christ-centered residential facility focused on mental health and substance abuse. He finds joy and fulfillment working with “difficult” clients that challenge his heart and clinical skill set. It is his hope and desire that each resident that passes through Clearfork Academy will be one step closer to their created design. Austin’s greatest pleasures in life are being a husband to his wife, and a father to his growing children. He serves at his local church by playing guitar, speaking and helping with tech arts. Austin also enjoys being physically active, reading, woodworking, and music.
