A Dose of Dopamine
In the Bloodstream
Slowed Reaction Time
Trouble for the Immature Brain
Defense Goes Down
The Effects of Marijuana on the Body
Marijuana comes from the Cannabis plant. The flowers, seeds, leaves, and stems of the plant must be shredded and dried before they can be used. Most people who use marijuana smoke it, but it can be mixed into food, brewed into tea, or even used in a vaporizer. One of the ingredients in marijuana is a mind-altering chemical called delta-9-tetrahydrocannabinol (THC).
When you inhale marijuana smoke into your lungs, it is quickly released into your bloodstream on its way to your brain and other organs. It takes a little longer to be absorbed when you eat or drink it.
The effects of marijuana on the body are immediate. Longer-term effects may depend on how you take it, how much you take, and how often you use it. Since its use has long been illegal in the United States, large-scale studies have been difficult to manage.
In recent years, the medicinal properties of marijuana are gaining acceptance in mainstream America. Medical marijuana is now legal in 23 states and the District of Columbia. THC and another ingredient called cannabidol (CBD) are the main substances of therapeutic interest. National Institutes of Health-funded research into the possible medicinal uses of THC and CBD is ongoing.
In addition to medicinal use, recent legislation has made marijuana a legal recreational drug in Colorado and Washington State. With the potential for increased recreational use, knowing the effects that marijuana can have on your body is as important as ever.
Much like tobacco smoke, marijuana smoke is made up of a variety of toxic chemicals (including ammonia and hydrogen cyanide) that can irritate your bronchial passages and lungs. If you’re a regular smoker, you’re more likely to wheeze, cough, and produce phlegm. You’re also at increased risk of bronchitis and lung infections. Marijuana may aggravate existing respiratory illnesses like asthma and cystic fibrosis.
Marijuana smoke contains carcinogens. It has the potential to elevate your risk of developing lung cancer. However, studies on the subject have had mixed results. According to the National Institute of Drug Abuse (NIDA), there is no conclusive evidence that marijuana smoke causes lung cancer. More research is needed.
THC moves from your lungs into your bloodstream and throughout your body. Within minutes, your heart rate may increase by 20 to 50 beats per minute, according to the NIDA. That rapid heartbeat can continue for up to three hours. For people with heart disease, this faster heartbeat could raise the risk of heart attack.
One of the telltale signs of recent marijuana use is bloodshot eyes. They look red because marijuana causes blood vessels in the eyes to expand or dilate. Marijuana may help stop the growth of blood vessels that feed cancerous tumors.
Central Nervous System
When you inhale marijuana smoke into your lungs, it doesn’t take long for THC to enter your bloodstream. From there, it is quickly transported to your brain and the rest of your organs. When you get marijuana from food or drink, it is absorbed a little more slowly.
THC triggers your brain to release large amounts of dopamine, a naturally occurring “feel good” chemical. That’s what gives you a pleasant “high.” It may heighten your sensory perception, as well as your perception of time. In the hippocampus, THC changes the way you process information, so your judgment may be impaired. It may also be difficult to form new memories when you’re high.
Changes also take place in the cerebellum and basal ganglia, upsetting your balance, coordination, and reflex response. All those changes mean that it’s not safe to drive.
Very large doses of marijuana or high concentrations of THC can cause hallucinations or delusions. According to the NIDA, there may be an association between marijuana use and some mental health problems like depression and anxiety, but more research is needed to understand the connection. In people who have schizophrenia, marijuana use can make symptoms worse.
When you come down from the high, you may be tired or feel a bit depressed. In some people, marijuana can cause anxiety. About nine percent of marijuana users develop an addiction, according to the NIDA. Symptoms of withdrawal may include irritability, insomnia, and loss of appetite.
In young people whose brains are not yet fully developed, marijuana can have a lasting impact on thinking and memory skills. If you use marijuana when pregnant, it can affect the brain of your unborn baby. Your child may be more prone to trouble with memory, concentration, and problem-solving skills.
THC can lower pressure in the eyes, which can ease symptoms of glaucoma for a few hours. According to the American Academy of Ophthalmology, more research is needed to understand the active ingredients in marijuana and whether or not it’s a good treatment for glaucoma.
The pharmacologic effect of marijuana extends throughout the central nervous system. It is thought to ease pain and inflammation. It may also be of use in controlling spasms and seizures.
Smoking marijuana can cause stinging or burning in your mouth and throat. When you take oral THC, it is processed in your liver. Marijuana can ease nausea and vomiting. It can also increase appetite, which can be useful to people living with cancer or AIDS.
Some research indicates that THC affects the immune system. Studies involving animals showed that THC might damage the immune system, making you more vulnerable to illness. Further research is needed.