Cannabis
Overview
Cannabis, also called marijuana, weed or pot refers to the dried flowers of the Cannabis sativa and Cannabis indica plants. The main active chemical in cannabis is THC (delta-9-tetrahydrocannabinol). Of the roughly 400 chemicals found in the cannabis plant, THC affects the brain the most.
About half of the states in the United States have legalized adult recreational use of cannabis (age 21 or older). In Texas, cannabis usage and possession for any use is still illegal. A conviction for possession of up to two ounces of cannabis can result in a jail sentence of up to six months and a fine of up to $2,000. Learn more about Texas cannabis laws from UT Austin Legal Services for Students.
Cannabis is one of the most used drugs in the United States. The 2021 National College Health Assessment for The University of Texas at Austin found that 36% of students reported having ever used cannabis.
Cannabis Use
Cannabis can be used in a variety of ways, including:
- Smoked in joints (similar to cigarettes), blunts (similar to cigars), bongs (a large pipe) or smaller pipes
- Inhaled through electronic vaporizing devices
- Mixed or infused into food (edibles) and drinks
- Smoking THC oils and concentrates, called dabbing. This is very dangerous as the THC is highly concentrated. Dabbing has been linked to lung injury and physiologic and psychological disorders.
Effects of Cannabis
People who use cannabis may experience a “high” or feelings of heightened mood, euphoria, relaxation and appetite stimulation. Long-term effects of cannabis smoking is associated with an increased risk of some respiratory problems, including an increase in cough, mucus production, airway inflammation and wheezing – similar to that of tobacco smoking. Cannabis withdrawal symptoms include increased anxiety, increased irritability, disrupted sleep, disrupted appetite and physical tensions such as headaches.
Adverse effects of cannabis use may include:
- Increased heart rate
- Increased blood pressure
- Decreased functioning of short-term memory
- Dry mouth
- Impaired motor skills
- Paranoia
- Anxiety
- Anxiety attacks
- Decreased muscle movement in the digestive system
- Some research has indicated that cannabis use may worsen pre-existing mental conditions, such as schizophrenia.
Medical Use of Cannabis
As of 2023, 38 states have legalized cannabis for medical use. In Texas, medical use of low-THC cannabis is legal for patients who participate in the Texas Compassionate Use Program, which is only open to patients with certain conditions.
Cannabinoids (components of cannabis plants) have been used ease symptoms caused by certain medical conditions, including pain, nausea, vomiting and loss of appetite. Common medical conditions that cannabis can be used to treat are cancer, HIV/AIDS, seizures and epilepsy, glaucoma, Alzheimer’s disease, multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS) and severe nausea, vomiting or chronic pain.
Cannabis FAQs
Does smoking cannabis impact memory?
Yes. Smoking cannabis can interfere with learning and memory. Occasional users experience lasting effects on cognitive functioning, including memory, for up to 48 hours after smoking. Habitual users experience ongoing impaired ability to learn new information, which continues for up to several weeks after quitting use.
Is cannabis addictive?
It is possible to develop a cannabis use disorder, meaning someone is unable to stop using cannabis even though it is causing health and social problems in their lives. One study found that 15% of current cannabis users met the criteria for having a cannabis use disorder. Some symptoms of cannabis use disorder include not being able to quit using cannabis or reduce the amount used, not engaging in school, work or social activities because of cannabis use and experiencing an urge to use cannabis when not using it. If you are concerned about yourself or a friend, the Counseling and Mental Health Center’s Substance Use Support Team is available for students who have questions about their own or someone else’s substance use.
Can smoking cannabis negatively affect the immune system?
Most likely, according to the majority of research. Smoking cannabis damages the cells in the lungs, which protect the body against inhaled microorganisms. It also decreases the ability of the immune cells in the lungs to fight off fungi, bacteria and tumor cells.
Can smoking cannabis cause lung cancer?
The association between smoking cannabis and lung cancer remains unclear. Cannabis smoke contains more of the harmful carcinogens (substances capable of causing cancer) than a comparable quantity of unfiltered tobacco smoke. The deeper inhalations and longer breath-holding of cannabis smokers also result in greater exposure of the lung to the tar and carcinogens in the smoke. However, some studies have failed to show an association between lung cancer and smoking cannabis because many cannabis users also smoke tobacco.
How long can the effects of smoking cannabis last?
The length of the effects of smoking cannabis will differ by individual and can be affected by length of use, tolerance and body composition. Tetrahydrocannabinol (THC), the main active ingredient in cannabis, is extremely fat-soluble, which means it is stored in the body's fatty tissues and can slowly enter the bloodstream for up to two days after smoking. For habitual users, it can last for over two days.
Can smoking cannabis change your mood?
Yes. Some users may experience heightened mood, euphoria, relaxation and appetite stimulation. Others may experience mild flashbacks, anxiety or panic attacks, and cannabis has been shown to heighten certain preexisting psychological conditions such as anxiety and panic disorders.
Is it legal to drive if I have consumed cannabis?
Driving under the influence of cannabis is illegal and dangerous. Cannabis impairs skills and functions needed for safe driving including reaction time, ability to make decisions, coordination and perception. Legal consequences for driving while under the influence of alcohol or drugs include fines, time in jail and loss of driver’s license.
How does cannabis impact sleep?
The effects of cannabis on sleep can vary depending on several factors including the strain of cannabis, dosage, individual tolerance and frequency of use. There is little evidence that supports using cannabis products for sleep. The potential for dependence, withdrawal and sleep disruption when using cannabis for sleep should also be considered.