Do you know the short- and long-term effects of weed? Read our article on marijuana side effects and discover it’s impact on your brain and body.
In light of the rapidly shifting legal landscape surrounding both medical and recreational marijuana, we have seen an increased interest in the potential short-term and long-term side effects of weed. Marijuana—the greenish-grey leaves and flowers of the Cannabis Sativa plant—can be smoked, vaporized, ingested, or applied topically to the skin. Most people use the drug for recreational purposes; however, a growing number of patients now use marijuana to manage chronic medical conditions.If you’re considering marijuana for therapeutic or recreational purposes, familiarizing yourself with the spectrum of marijuana side effects is an important step in preparing yourself for a positive experience.
How Does Marijuana Affect the Brain and Body?
Marijuana interacts with your brain and body through our endocannabinoid system; a series of receptors located throughout our central and peripheral nervous system which are responsible for maintaining internal stability. When you inhale marijuana, chemical compounds within the drug—known as phytocannabinoids—are rapidly absorbed into your bloodstream and carried towards these endocannabinoid receptors.
When the phytocannabinoids interact with these receptors, they mimic the effects of our body’s own cannabinoid-like chemicals—known as endocannabinoids—causing a diverse range of effects from therapeutic to potentially harmful. If you consume edible marijuana or apply a topical lotion, the phytocannabinoids are absorbed more slowly by the body. In this case, effects are generally felt within 30 minutes, as opposed to almost immediately.Marijuana side effects depend on a strain’s cannabinoid profile. That’s because marijuana can contain over 100 different cannabinoids. However, the main cannabinoid present in all marijuana strains is delta-9-tetrahydrocannabinol (THC). It’s responsible for the drugs mind-altering effects and the reason users experience an intoxicating high. Cannabidiol (CBD) is the second most prevalent cannabinoid. It’s considered a non-intoxicating cannabinoid as it does not give users the typical high associated with marijuana.
Both of these cannabinoids have specific therapeutic properties:
- THC is a natural analgesic, antiemetic, and appetite stimulant. In 1992, the United States Food and Drug Administration (FDA) approved a synthetic version of THC for the treatment of anorexia in AIDS patients, and in 1985, another synthetic version was approved to prevent nausea and vomiting in chemotherapy patients.
- CBD has anti-inflammatory, anti-seizure, and analgesic properties. In 2018, the FDA approved a purified version of CBD for the treatment of two rare forms of childhood epilepsy. It is commonly used to manage anxiety, in addition to patients who suffer from insomnia and neuropathic pain.
While marijuana has immense therapeutic potential, which is recognized by the FDA, there are also adverse side effects that could be harmful to your health in the short and long term.
Short-Term Effects on the Brain
The short-term effects of marijuana on the brain can include:
- Impaired Memory: THC changes the way information is processed within the hippocampus—a region within the brain responsible for forming short-term and long-term memories.
- Disrupted Motor Control: Marijuana slows down the transmission of motor neurons, which can impair coordination and reaction times. You should not operate heavy machinery or drive a vehicle while under the influence of THC.
- Impaired Cognition: THC can temporarily impair your decision-making skills, problem-solving ability, and concentration. You may lose your sense of time and ability to judge distance.
- Disturbances in Mood: Marijuana triggers the release of a chemical called dopamine, which can provide a euphoric, relaxed feeling. However, marijuana can also exacerbate anxiety or depression.
- Altered Senses: THC alters your sensory perception, which can make colors appear brighter and more vivid.
- Psychotic Symptoms: At high doses, marijuana can cause psychotic episodes characterized by hallucinations, delusions, and psychosis. Psychosis is a mental state during which a person loses the capacity to tell what’s real from what isn’t. 
Emerging evidence suggests that CBD may help lessen the adverse psychoactive effects of THC. 
Short-Term Effects on the Body
The short-term effects of marijuana on the body can include:
- Decreased Blood Pressure: Marijuana can lower your blood pressure, which can cause some people to faint or pass out. It also causes the blood vessels to dilate, which is the reason why bloodshot eyes are a tell-tale sign of marijuana use.
- Increased Heart Rate: Using marijuana makes the heart beat faster. In fact, your heart rate can rise by 20 to 50 beats per minute for up to 3 hours.  If you have a heart condition, this could increase your risk of a heart attack or stroke.
- Damages Blood Vessels: Smoking marijuana or breathing in second-hand smoke immediately damages your blood vessels, which can increase your chances of developing hardened or clogged arteries. 
Acute Marijuana Impairment
Marijuana use can increase your risk of falls and accidents that lead to injury or death. In fact, marijuana is the most common illicit drug reported in connection with fatal accidents in the United States.  As a result, driving under the influence of marijuana is a crime in some states. That’s because marijuana impairs your coordination, reaction time, motor skills, and ability to judge distance—just like alcohol.
How Does Marijuana Affect Your Overall Health?
Marijuana use has an accumulative effect on the physical and mental health of long-term users. Long-term use is classified as daily, or near-daily, use that continues for weeks, months, or years. Once you stop using, the long-term effects of weed can persist and even become permanent.
Long-term Effects on Mental health
- Brain Development: Regular marijuana use over time can reduce your memory, attention, and intelligence. These effects appear to be worse when marijuana use begins during adolescence, which is a critical time for brain development.  However, recent studies, involving twins found no difference in intelligence. 
- Schizophrenia: Marijuana can increase the risk of developing mental illnesses, such as schizophrenia and psychosis, especially among those who use cannabis daily, start during youth, or have a family history.
- Depression and Anxiety: Frequent marijuana use over an extended period of time is associated with an increased risk of anxiety disorders, depression, and suicide. High-THC strains are the most commonly associated with anxiety and panic disorders.
Addiction & Dependence: Contrary to popular belief, it is possible to become addicted to or physically dependent on marijuana. People who use cannabis over an extended period of time can develop Cannabis Use Disorder.
Long-Term Effects on Physical Health
- Respiratory System: Smoking marijuana, regardless of whether it’s from a joint, bong, bowl or blunt, can cause long-term damage to your bronchial passages and lung tissues. That’s because marijuana smoke contains many of the same toxins, irritants, and carcinogens as tobacco smoke. Regular marijuana smokers are more likely to cough, wheeze, and produce phlegm, as well as suffer from bronchitis and lung infections. While more rigorous research is needed, the evidence does indicate that inhaling marijuana smoke can increase your risk of lung cancer. 
- Pregnancy: Inhaling marijuana smoke during pregnancy can expose the growing fetus to toxic chemicals, which can lead to health concerns, including attentional problems, hyperactive behaviors, and memory difficulties. .
As mentioned earlier, marijuana is addictive, especially for youth who are particularly vulnerable. An estimated 1 in 10 marijuana users will become dependent or addicted to the substance. This rate rises to 1 in 6 for people who begin using marijuana during adolescence. 
Signs of addiction, or problematic marijuana use, may include the following behaviors:
- No longer able to fulfill school, work, or home duties.
- Choosing weed over social or recreational activities.
- Being unable to control the dose or frequency of marijuana use.
Regular marijuana users can develop a tolerance, which means a larger dose is needed to achieve the same effects. Building up tolerance with daily usage can also lead to addiction.
It is possible to consume too much marijuana; however, there has never been a fatal overdose recorded. Unlike opioids and alcohol, marijuana cannot shut down your body’s respiratory or circulatory systems.
Although marijuana has anti-anxiety and anti-nausea effects, too much marijuana can have the opposite effect. Signs that you’ve had too much can include vomiting, hallucinations, panic attacks, anxiety, and paranoia. However, according to a report from the World Health Organization, pure CBD has no potential for abuse or dependence in humans and “to date, there is no evidence of public health-related problems associated with the use of pure CBD.” 
Risk of Illegal Marijuana
Medical marijuana is subject to industry-wide rules and standards, covering everything from production practices to packaging and potency. Black market marijuana, on the other hand, does not offer the same consumer protections. For example, illegal cannabis often has higher concentrations of THC, which could result in more intense psychoactive effects. The plant may also be contaminated with other compounds such as heavy metals, pesticides, molds or fungus.