What Is Marijuana?
Marijuana is a shredded, green-brown mix of dried flowers, stems, and leaves from
the plant Cannabis sativa. A stronger form of marijuana, called hashish (hash), looks
like brown or black cakes or balls. The amount of THC (the active ingredient) in marijuana
and marijuana products has increased greatly over the years.
Marijuana is usually rolled and smoked like a cigarette (joints or doobies), or
put in hollowed-out cigars (blunts), pipes (bowls), or water pipes (bongs). Recently,
it has become increasingly popular for people to inhale marijuana or stronger marijuana
extracts using a vaporizer (called "vaping" or "dabbing"). Some people mix it into
food or brew it as a tea.
There is also "synthetic marijuana" — manmade drugs that are chemically similar
to THC — that can be dangerously strong. Names for these drugs include "K2,"
"Spice," and "Herbal Incense." They can be so potent that overdose deaths
have happened.
Short-Term Effects
The main active chemical in marijuana is THC (delta-9-tetrahydrocannabinol). When
someone smokes marijuana, THC goes from the lungs into the bloodstream. From there,
it ends up in the brain and other organs.
THC connects with a receptor on nerve cells in the brain. The marijuana "high"
results from THC's effects on the nerve cells that control sensory perception and
pleasure.
THC also connects with receptors on nerve cells in other parts of the brain that
affect thinking, memory, coordination, and concentration. This can cause unwanted
side effects, including:
- trouble thinking and problem solving
- problems with memory and learning
- loss of coordination
- distorted perception
These side effects are temporary, but they can make it dangerous to do things like
drive while under the influence of marijuana.
People also might notice other short-term side effects of using marijuana, such
as:
- an increased appetite
- feeling lightheaded or drowsy
- a decrease in inhibitions
Long-Term Effects
Research has found that people who use marijuana over a long period of time can
have more lasting side effects. For example:
Changes in the brain. Marijuana can affect the parts of the brain
that play a role in our ability to remember, multitask, and pay attention.
Fertility issues. Animal studies suggest that using a lot of marijuana
might be linked to decreased sperm count in men and delayed ovulation in women. Pregnant
women who use marijuana might be more likely to have babies with developmental and
behavioral problems.
Respiratory problems. People who smoke marijuana a lot can develop
problems with the respiratory system — like more mucus, a chronic cough, and
bronchitis.
Immune system problems. Using marijuana a lot might make it harder
for the body to fight off infections.
Emotional problems. People who use a lot of marijuana are more
likely to say they notice signs of depression
or anxiety. If someone
has a condition like schizophrenia or bipolar
disorder, marijuana can sometimes make symptoms worse.