Marijuana itself is generally seen as a grey or brownish green mixture of dried matter. These dehydrated and shredded leaves and flowers of the cannabis sativa plant can be rolled as a cigarette and smoked. 

There are hundreds of slang terms for marijuana, including “pot,” “herb,” “weed” and “Mary Jane.” Although the drug is usually smoked as a cigarette (called a joint or a nail), it can also be inhaled through a pipe or bong. In recent years, cigars that have been emptied of tobacco and re-filled with marijuana have been called “roaches.” Some marijuana users also combine the drug into foods or brew it as a tea.

Understanding the Short-Term Effects of Marijuana

Some of the nerve cell membranes in our bodies contain protein receptors which bind to THC. These “stations” are known as cannabinoid receptors. Once the presence of marijuana is perceived at these different points in the nervous system, the short-term effects of consuming begin to manifest. In addition to a hazy, lightheaded feeling, some users have reported experiencing problems with memory and learning as well as distorted perception, difficulty in thinking and problem solving. Loss of coordination, increased heart rate, anxiety, and panic attacks are also not uncommon amongst frequent marijuana users.

Health Hazards and Adverse Reactions Linked to Cannabis

Effects of Marijuana on Life, Learning and the Brain

Research indicates that the parts of the brain that are linked to pleasure, memory, perception, movement and thinking are the parts most densely populated with cannabinoid receptors. In other words, consumption of marijuana simply overactivates these sensory channels, causing distorted perceptions and other effects.

It has been clearly outlined by a number of different studies that marijuana use has the potential to degrade its users’ quality of life. Regular, heavy marijuana users commonly report poor mental and physical health as well as a dissatisfaction with life, relationship issues as well as trouble learning and remembering which can greatly affect both one’s academic and professional success.

Effects on the Lungs

Although marijuana has developed somewhat of a reputation for being a “natural” drug, the substance itself actually contains a number of toxic substances at a greater potency than regular tobacco cigarettes. The main psychoactive chemical in marijuana is called delta-9-tetrahydrocannabinol, or THC.

A regular marijuana smoker may experience many or all of the same health and respiratory issues as a tobacco smoker (such as chronic coughing, bronchitis, chest colds or regular infections.) Continued marijuana smoking can lead to the destruction of lung tissue and more serious health issues as a result.

Effects on Heart Rate and Blood Pressure

Shortly after one consumes marijuana, the heart rate is seen to rise by anywhere between 20-100%. This increased demand on the cardiovascular system can lead to irregular heart rhythms or palpitations. In one recent study reported by the National Institute on Drug Abuse (NIDA), marijuana users were seen at an elevated risk of heart attack while under the influence of THC (an estimated 4.8-fold increase in the risk of heart attack.)

As with many other drugs, marijuana consumption can increase risk of adverse cardiac events through overload on the cardiovascular system.

Effects of Heavy Marijuana Use on Learning and Social Behavior

Marijuana use has long since been linked to poor academic performance, trouble learning, memory and recall impairment. Further, a number of studies indicate the lasting negative potential of regular marijuana use on a young person’s ability to learn and remember.

As reported by NIDA, marijuana users who began using the drug at a young age were seen with lacking IQ scores as well as unrestored cognitive abilities in their later adult lives.

Socially, marijuana use is linked to frequent job turnover, higher likelihood of dropping out of school as well as personal health and relationship problems.

Marijuana’s Effects on Pregnancy

A mother’s health during pregnancy should be safeguarded heavily. The use of illicit street drugs, including marijuana, should be avoided completely during pregnancy to avoid developmental health problems or miscarriage.

Further, a nursing mother who uses marijuana should be aware that she will likely pass some of the THC to her infant child through breast milk. This, too, can cause both mental and physical developmental issues.

Is Marijuana Addictive?

Likely due to the common misperception that marijuana is safe and natural, cannabis is believed by many to be a non-addictive and harmless drug.

Roughly 9% of those who use marijuana become addicted to the drug—a number which is seen to increase as the starting ages grow younger. Further, long-term and regular marijuana users who attempt to quit very frequently experience withdrawal symptoms including nausea, panic attacks and anxiety, drug cravings, irritability and sleeplessness.

Extent of Use: Monitoring the Future Study (MTF)

The NIDA-funded Monitoring the Future study provides an annual assessment of drug use in participating high school students and young adults nationwide. Most recent survey results improvements and reductions in marijuana use, although experts worry about increases in the abuse of other substances like prescription drugs and club drugs (not included on chart).

Percentage of 8th-Graders Who Have Used Marijuana: Monitoring the Future Study

	2010	2011	2012	2013
Ever Used (Lifetime)	17.3%	16.4%	15.2%	16.5%
Used in Past Year	13.7%	12.5%	11.4%	12.7%
Used in Past Month	8.0%	7.2%	6.5%	7.0%
Daily Use	1.2%	1.30%	1.1%	1.1%