Marijuana Pros and Cons

What is it about marijuana that has practically put all sectors of human society in a constant state of ambivalence for hundreds of generations? Is it good or bad, do we love it or hate it, should it be legal or not, eat it or smoke it? etc.  

The main psychoactive agent in marijuana is delta 9-Tetrahydrocannabinol or THC for short. It is the marijuana plant’s claim to fame, its most psychoactive chemical compound or its most potent.

The plant’s leaves and buds produce resin, from which THC is extracted. Over 500 other compounds (yes over 500 – we did say it is a lot of things) chemically related to THC can be extracted as well, among them more than 100 are called cannabinoids.

History of Marijuana

Marijuana use may be traced as far back as the time of the ancients, but believe it or not, it wasn’t until 1964 when Dr. Raphael Mechoulam and his colleagues Dr. Haviv Edery and Dr. Yehiel Gaoni were finally able to isolate and elucidate which among the compounds found in the plant was causing all the mental stimulation that has brought marijuana to the attention of the world.

Dr. Mechoulam, dubbed “The Father of Cannabis” was with the Weizmann Institute of Science in Rehovot, Israel at the time and looking for research subjects. From his readings, he realized just how little was known about the compounds in cannabis compared to the coca leaf (for cocaine) and the opium poppy (for morphine) which have been around for some 150 years already. He found it strange that the active component of cannabis was uncknown.2 He then began his research using the 5 kilograms of Moroccan hash donated by their local police upon his request. With the help of his colleagues, he was soon able to painstakingly but successfully ISOLATE each and every compound present in the cannabis plant.

But which ones were psychoactive? Which ones were causing the “high” associated with marijuana? Dr. Mechoulam’s team tested each individual compound on monkeys and to their surprise only one of those compounds, delta9-tetrahydrocannabinol (THC) produced any effect. The monkeys looked sedated or drunk.

He took home a dose of THC and asked his wife to put it in her cake recipe. That was the first and only time the Father of Cannabis got high. More importantly, his findings are proving useful to present-day studies about medical marijuana – that each person has a different reaction to THC. One of his friends demonstrated trance-like behavior, another showed paranoia, someone talked non-stop and another was all giggly.3 

Street Names for Marijuana

Marijuana is popularly called by the following street names:

  • Blow
  • Bud
  • Dope
  • Draw
  • Ganja
  • Grass
  • Hash
  • Herb
  • Mary Jane
  • Pot
  • Puff
  • Wacky backy
  • Weed

Marijuana Drug Type

THC has stimulant, depressant, and hallucinogenic properties.4 As Dr. Mechoulam’s experiment over 50 years ago, the drug affects each person differently:

  • As a stimulant, THC boosts confidence, enhances mood, raises self-esteem and makes some people feel elated. These stimulating properties of THC cause a person to become ecstatic, lively and talkative.
  • As a depressant, THC acts like a mild sedative, causing drowsiness and extreme relaxation. Others become withdrawn. 
  • As a hallucinogen, THC distorts a person’s perception. Colors and sounds become heightened. Hallucinogens can cause paranoia.

Marijuana DEA Drug Class

Marijuana is still a Schedule I drug. Schedule I substances, drugs or chemicals have a high potential for abuse with no current medical use. Examples of other drugs in this class are:

There is a current debate about possibly rescheduling marijuana to Schedule II or de-scheduling it altogether in light of marijuana legalization in 29 states. The problem here is that the terms “medical marijuana”, “low-THC” and “high CBD” are indiscriminately and interchangeably used. The legalization of medical marijuana has many pros and cons. A “medical marijuana” product may contain a wide combination of cannabinoids, THC included. “High-CBD” products may perhaps simply contain more CBD than a “medical marijuana” product, but still contain THC.5 Unless and until these complicated details are resolved, this scheduling debate will continue to rage.

Forms and Routes of Administration

THC may be produced from different parts of the marijuana plant.  

  • Herbal cannabis (marijuana) – This form consists of the dried leaves and flowers of the female plant. It looks like dried herbs and is smoked by itself or with tobacco. It may also be eaten/ingested by adding it to food products or brewed like tea.
  • Hash/Hashish – This is a strong form of marijuana with high THC It is extracted from the dried resin of the female plant and pressed into cakes, bars, balls, sticks, etc. Hash may be smoked or eaten by mixing with foods like brownies.
  • Cannabis oil/Hash oil – Less common but is the strongest form available, with a high THC If the oil is dark red or gold like honey, it is considered high quality. It is extracted thru the use of solvents.

Effects of THC on the Brain

There are two kinds of cannabinoids that affect the body: endocannabinoids and phytocannabinoids.

Anandamide is an endocannabinoid (endogenous cannabinoid neurotransmitter). Endogenous means it is naturally produced in our brains. It sends chemical messages between neurons in the nervous system. Anandamide regulates our thinking processes, memory, moods, senses, sleep, coordination, movement, appetite and our perception of time.

THC is a phytocannabinoid. Phyto is the Greek root for “plant”. THC, therefore, is a cannabinoid that comes from a plant; in this case, marijuana.

Anandamide and THC are chemically similar in structure. The body, therefore, is able to recognize THC allowing it to attach to the same cannabinoid receptors that anandamides bind to and affecting the same physical and mental functions mentioned above. For example, THC is able to change the workings of areas of the brain that form new memories and shifts a person’s focus. It results in a person’s inability to learn new tasks and do complicated jobs. THC also interferes with the cerebellum and basal ganglia, resulting in impaired balance, coordination, posture and reaction time. Large doses of THC may also cause acute psychosis – delusions, hallucinations and losing a sense of self. THC also activates the brain’s reward system and the responses to pleasurable activities like sex and eating.

Short-Term Effects of THC

The side effects of THC begin to manifest within minutes of use and last for only a short time, 30 minutes on the average. Users, therefore, feel driven to “chase the high” by continuing to repeat the experience.

  • Altered perception of time and space
  • Altered sleep
  • Amnesia
  • Confusion
  • Decreased concentration
  • Delusions/Hallucinations
  • Depression
  • Detachment
  • Dizziness
  • Elevated heart rate
  • Euphoria
  • Extreme relaxation
  • Increased appetite
  • Lack of coordination
  • Lack of energy
  • Mania
  • Muscle weakness
  • Panic
  • Paranoia
  • Poor motor control
  • Prone to laughter
  • Reduced alertness
  • Reduced anxiety
  • Reduced pain
  • Short-term memory impairment
  • Slurred speech
  • Talkativeness

Long-term Effects of THC

Addiction is the inevitable effect of long-term use. Relationships suffer, social activities are neglected, and school and work are affected negatively resulting in poor production and performance. Other long-term effects include:

  • Chronic bronchitis
  • Depression
  • Impaired growth of epithelial cells in lung tissue
  • Increased anxiety
  • Increased risk of heart attack
  • Increased risk of lung cancer
  • Lung irritation from exposure toxins found in marijuana
  • Palpitations and arrhythmias
  • Psychosis
  • Schizophrenia

Marijuana Withdrawal Symptoms

Some people argue that marijuana is not addictive but many studies show that it is possible, even if it occurs much less compared to other drugs. When one suddenly stops using marijuana some of the following withdrawal symptoms may be experienced.6

  • Headaches
  • Chills
  • Irritability
  • Anxiety
  • Shakiness
  • Depression
  • Fever
  • Weight loss
  • Low appetite
  • Extreme sweating
  • Restlessness
  • Stomach pain
  • Difficulty sleeping
  • Tiredness during the day

Marijuana use is so widespread that it routinely tested during pre-employment drug screening and is included in the so-called SAMHSA-5 or the minimum standard for workplace drug testing.7 This basic 5-panel drug test checks for:

  1. Amphetamines
  2. Cocaine
  3. Marijuana (THC)
  4. Opiates
  5. Phencyclidine (PCP)

Screening Cut-off and Detection Time for THC 


Screening Cut-off

GC/MS Cut-off (confirmatory)

Approximate Detection Time

Urine test

 50 ng/mL

 15 ng/mL

15-30 days

Saliva test

 50 ng/mL

 15 ng/mL

 6-12 hours


 1 pg/mg

 50 pg/mg

From 3-6 months after use

Hair follicle test

 0.1 - 1 pg/mg

 0.3 - 50 pg/mg

From 5-7 days after use up to 90 days


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