Short- & Long-Term Effects of Weed

Marijuana (also known as weed, pot, cannabis, or dope) can have unwanted and lasting effects on a person’s health and well-being. Keep reading to learn more about the different risks of marijuana use and misuse and how to get help for marijuana addiction.

Short-Term Effects of Marijuana

Marijuana and other forms of cannabis contain the psychoactive ingredient tetrahydrocannabinol (THC), which can produce a range of immediate and short-term effects on a person’s mind and body.

The most common short-term effects of weed include:¹

• Bloodshot eyes.
• Increased appetite.
• Dry mouth.
• Rapid heart rate.

These effects can also be accompanied by:¹

• Lethargy.
• Short-term memory loss.
• Trouble thinking clearly or making decisions.
• Impaired motor skills (e.g., walking, talking).
• Distorted sense of time.

Most people use marijuana to feel the euphoric “high” and sense of relaxation associated with the drug—but not everyone’s experience is a happy one. Some people may feel anxiety, fear, and panic, especially when the drug is used in large amounts or high-potency doses. They may also experience acute psychosis that involves hallucinations and delusions.²

Effects will vary depending on how much cannabis is used, the method of use (e.g., smoking, eating), a person’s tolerance to the drug, and other individual characteristics.¹

Short-term effects usually start within minutes of smoking weed and may last for several hours. If marijuana or cannabis is eaten or consumed via drink, the onset may be delayed for 30 minutes to an hour, and the effects could last somewhat longer than when the drug is smoked.^1,2 

Long-Term Effects of Marijuana

Over time, regular use of cannabis or marijuana may impact a person’s health and cognitive functions.

In general, the long-term effects and risks of marijuana use can include:^3–7

• Damage to vital organs, such as the lungs, brain, and heart.
• Weakening of the immune system.
• Chronic or permanent problems with attention, memory, and learning.
• Cannabinoid hyperemesis syndrome, which can result in regular cycles of severe nausea, vomiting, and dehydration that may require emergency medical attention.

Long-term marijuana use can also affect a person’s mental health and has been linked to social anxiety, depression, and schizophrenia. But more research is needed in this area to better understand the complex relationship between cannabis use and mental health disorders.⁸

Additionally, regular and frequent marijuana use can lead to physical dependence and addiction, as well as withdrawal if a person suddenly stops using the drug.³

Effects of Marijuana on the Lungs

Smoking marijuana can affect a person’s respiratory system, causing scarring to the lung tissues and damaging the small blood vessels.⁴

Like the smoke from tobacco or cigarettes, marijuana smoke may contain toxins, carcinogens (cancer-causing chemicals), and other irritants that are harmful to the lungs.⁴

Additionally, limited scientific evidence suggests that secondhand marijuana smoke can be as harmful to the heart and blood vessels as secondhand tobacco smoke. But researchers are still investigating this connection.³

However, they do know that the toxins and tar present in marijuana smoke can impact children, people with asthma, and other vulnerable individuals.³

Effects of Marijuana on the Brain

Marijuana use directly affects the brain and its functions. As mentioned above, marijuana or cannabis can alter a person’s senses and impair their coordination, movement, attention, memory, and thinking.⁵

Research has also shown that when teens use marijuana it can impact their brain development, leading to decreased attention span, memory, and learning abilities. These changes can last a long time or may even be permanent.⁵

In addition, some studies link marijuana use to lower IQ scores and poorer performance in school. However, researchers are still working to fully grasp the extent of these problems and their connection to marijuana use.^3,5,9

Effects of Weed on the Heart

The chance of heart attack and stroke may be more likely for older individuals or people with pre-existing heart conditions.³

Additionally, the toxins from marijuana smoke that can affect the lungs can also affect the cardiovascular system and lead to a greater risk of heart disease and other vascular diseases.⁶

Effects of Marijuana Use During Pregnancy

Marijuana use during pregnancy can affect your baby’s health and brain development.^3,10

Studies have linked marijuana use while pregnant to lower birth weights and higher rates of preterm births and behavioral problems. Additionally, research suggests that children exposed to marijuana before birth can have more issues with attention, memory, and problem-solving than children who aren’t exposed.^3,10

The psychoactive active effects of THC can also be passed to babies through secondhand smoke and breastmilk.^3,10

Treatment for Marijuana Addiction

If you or a loved one has lost control of their marijuana use, professional addiction treatment can help. At Sunrise House Treatment Center, we offer personalized, evidence-based care designed to meet each person’s individual needs.

Our inpatient rehab in New Jersey also specializes in the treatment of co-occurring disorders for those struggling with addiction and other mental health conditions at the same time.

If you’re ready to begin the path to recovery, contact us at  to learn more about the different types of addiction treatment we provide. Our staff is available around the clock to answer questions about using insurance to pay for rehab and other ways to pay for rehab and to help you get admitted today.

You can also quickly verify your health insurance coverage by filling out this confidential .

You are not alone. Call us at to get the support you need and deserve.