by Kat Austin August 04, 2020 11 min read

THC - Vida Optima™

THC, short for "tetrahydrocannabinol," is the most prevalent phytocannabinoid found in Cannabis. It is the chemical responsible for the psychoactive effects associated with marijuana.

A close up of colorful cannabis trichomes

THC can be found in the leaves and stems of cannabis plants, but is most concentrated in the trichomes (hair-like structures) found on the plant’s flowers.

Although THC use is limited by federal regulations, many local legislations have approved it for medicinal and even recreational use. Research regarding THC’s medicinal benefits is still limited, but there are multiple ailments listed as “qualifying conditions” in states that have approved medicinal use.

In fact, THC has even been used as the main component for some pharmaceuticals and is an increasingly popular addition to cancer therapy routines to help manage nausea, appetite loss, and pain.

With THC research efforts constantly evolving and more states legalizing the sale and use of cannabis products, it can be hard to see the full picture.

We’ll cover everything you need to know about THC, including where it comes from, legality concerns, and how and why it’s used down below.

Table of Contents
THC Effects
THC vs Other Cannabinoids
Is THC Legal?
How Does THC Work?
Potential Benefits of THC
Pharmaceutical Uses of THC
How Is THC Used?
Does THC Have Any Side Effects?
Is THC Safe?
Key Takeaways

THC Effects

THC is the psychoactive component found in cannabis, and it’s responsible for the “high” you may get from marijuana products.

These psychoactive effects are thought to mostly be the result of a dopamine response, but THC may also affect the hippocampus, the part of the brain involved with creating memories.

The effects from THC may take anywhere from 10 minutes to 2 hours to kick in depending on the consumption method used. The duration of the effects also varies greatly and may last anywhere from 2-8 hours.

CBD (a popular non-psychoactive cannabinoid) may potentially lessen the effects of THC, including negative effects like paranoia.

In general, the psychoactive effects of THC pose certain limitations for medicinal use. 

THC vs Other Cannabinoids

THC is the only phytocannabinoid that we know for sure has psychoactive effects, but over 100 different cannabinoids have been identified to date. Still, many of these minor cannabinoids appear in concentrations less than 2% and we still have a lot to learn about the role they play in cannabis’ effects on the body.

CBD is the most common cannabinoid aside from THC, and it’s becoming increasingly popular for its lack of psychoactive effects and widespread potential health benefits.

That’s not to say that other cannabis compounds are less important. Research has identified a selection of benefits related to lesser-known cannabinoids, like CBG and CBN, and terpenes, like pinene and myrcene.

In fact, one theory suggests that CBD, THC, and all other trace cannabinoids and terpenes may be more efficient when working as a group. This is because cannabinoids and terpenes are thought to act synergistically in many ways, a phenomenon often described as the “entourage effect.” 

For this reason, many people choose to use CBD and THC together, and many THC products are designed to offer a 1:1 ratio of THC:CBD. Many CBD users even choose full spectrum CBD, which has a THC content of up to 0.3%, as opposed to CBD isolate, which has no THC.

Is THC Legal?

A bud tender measuring out high-THC flower at a dispensary.

THC is derived from cannabis, a plant family that’s long fallen under the red tape of “restricted use." This makes it difficult to understand where and how to access legal THC products, and even makes it impossible for some people.

According to federal legislation, THC is still classified as a Schedule I substance, making it illegal. The manufacture, sale, and use of THC products is still punishable by federal law.

Many states have passed legislation of their own to allow the sale and use of THC products within their borders, usually with restrictions on where THC products can be purchased, and how much cannabis a person can possess at one time.

The 2018 update to the Farm Bill declared cannabis strains classified as "industrial hemp" and all of their naturally occurring derivatives (like CBD) legal, so long as they contain less than 0.3% THC. This means that CBD products may be a legal, accessible alternative to THC products in areas where cannabis sales are still prohibited.

Multiple attempts have been made to legalize cannabis on a national scale, but so far none have prevailed. Slowly but surely, more and more states are passing regulations to allow the sale of THC products, and many people expect this legislation to eventually reach a national level.

The federally illegal status of THC keeps cannabis products out of reach for some consumers, but it also poses other issues.

One major concern is the difficulty involved with conducting research on THC and cannabis products, including the difficulty of getting proper grants and federal funding for this research. Federal legalization is the main obstacle standing in the way of the research needed to help us understand THC’s full potential.

How Does THC Work?

THC is structurally similar to select endocannabinoids, or neurotransmitters found naturally in the body.

Because of these similarities, THC is able to bind with certain neuroreceptors within the Endocannabinoid System, or a collection of neurotransmitters and neuroreceptors found throughout the body in the brain, skin, and other major organs.

The Endocannabinoid System is responsible for many basic functions, like memory, thinking, pleasure, coordination, and sensory perception. The Endocannabinoid System also plays a role in regulating mood, appetite, immune functions, and more.

In other words, THC interacts with a bodily system that impacts most parts of daily life. The impact of the endocannabinoid system is far reaching and relies on a delicate balance of cannabinoids, which helps explain why THC impacts every person differently and why it may have such a broad range of benefits.

Potential Benefits of THC

THC’s medicinal potential has been acknowledged for quite some time, but researchers disagree on exactly how and when cannabis can be effectively used as a medicine.

Most frequently, THC is regarded as a potential alternative to opioids because of its ability to provide pain relief, potentially without the same serious side effects, like risk of dependency and overdose.

Another popular area of research is the use of cannabis for cancer and cancer-related symptoms. Some research has suggested that whole-cannabis extracts including THC may be effective anti-tumor agents, but this research is still widely inconclusive.

THC may also be debilitating in some ways (via psychoactive effects) that make it a less suitable option than traditional pharmaceuticals for some conditions.

Still, research regarding the benefits of THC, whole-plant cannabis extract, and synthetic THC formulations is on the rise. For now, we have the most evidence regarding THC’s positive potential for the following ailments:

  • Pain:THC (and multiple other cannabinoids) have been relentlessly targeted by researchers for their potential impact on pain, especially chronic pain that is difficult to treat. THC’s impact on pain may be the main reason that it is widely considered useful for a range of conditions that cause chronic pain, like fibromyalgia and endometriosis. Most of the research regarding THC’s pain-relieving potential focus on pain relief from whole-plant cannabis flower and not THC on it’s own.
  • Muscle spasticity: Although research is still inconclusive, THC is often sought after for it’s muscle relaxant properties. One placebo-controlled study found that THC may provide up to twice as much relief from muscle spasms in Multiple Sclerosis patients as the placebo. A 2014 systemic review found that oral cannabis extract may be effective for managing spasticity and painful muscle spasms in MS patients. Further research suggests that medical marijuana may have similar benefits for patients with Parkingson’s Disease.
  • Sleeplessness or insomnia: Many anecdotal reports suggest that THC may be a useful sleep aid with far fewer side effects compared to traditional sleep-inducing medications. There is some research to back this claim, including one study that calls THC a sedative. One study suggest that high-THC cannabis strains may reduce REM sleep, which means that it may reduce dreams. A synthetic THC-based prescription medication, Nabilone, was concluded as beneficial for reducing nightmares in patients with PTSD.
  • Glaucoma:Multiple research efforts have suggested that THC may reduce intraocular eye pressure, which may make it a suitable option for managing glaucoma.
  • Gastrointestinal Disease: One study suggests that cannabis may be useful for managing the symptoms of Inflammatory Bowel Disease, which is a blanket term for multiple conditions like Crohn's Disease and Colitis. In 2013, a study found that THC may reduce intestinal motility in patients with various gastrointestinal diseases, which could effectively alleviate spasms and pain in the colon and stomach.
  • Cachexia and anorexia:THC is well-known for inducing appetite, which may make it useful for managing AIDS or cancer-related cachexia (also referred to as wasting syndrome). Research also suggests that THC may have a positive effect on the psychological impacts of anorexia nervosa.

Although there is plenty of research surrounding the benefits of THC, some of which dates back decades, legal restrictions have largely prevented cannabis research from advancing in the U.S. Still, many other countries are working tirelessly to identify THC’s full medicinal potential.

Pharmaceutical Uses of THC

A syringe filled with THC concentrate

Although THC’s full potential is not yet understood, several pharmaceutical THC-based formulations have been approved for use in a research setting. Of these, three pharmaceutical medications have been approved for prescription use, including Sativex, Marinol, and Nabilone.

Sativex was approved in Europe in 2010, and it was the first prescription cannabis treatment in the world. It’s composed of both THC and CBD derived from cannabis. Although some applications are still in late trial phases, potential uses for Sativex include managing spasticity due to multiple sclerosis and managing intractable cancer-related pain.

Marinol is a synthetic version of THC that has been approved for multiple uses, including appetite stimulation, managing nausea and vomiting associated with chemotherapy, managing AIDS-related anorexia, and managing symptoms associated with multiple sclerosis.

Nabilone is also a synthetic THC formulation approved for the management of nausea and pain for patients undergoing popular cancer therapies.

Ultimately, THC research is heavily restricted across the globe, but many pharmaceutical companies have been able to acquire special permissions to formulate and test various THC products. Using synthetic cannabinoids is one way that these companies are able to work around legal restrictions.

Other THC-based pharmaceuticals are still under trial, but many research efforts are now gearing their efforts towards CBD-based formulations thanks to the increased accessibility of the non-psychoactive cannabinoid.

How is THC Used?

With so many potential benefits of THC, it's no surprise that the market is incredibly diverse.

In research, THC has been used intravenously, orally, by inhalation, and via other methods. Generally speaking, inhalation is the most common consumption method for THC, usually via smoking cannabis flower. THC vaporizers have also gained traction, and some people consider them a safer alternative to combustion (smoking) methods.

Of course, THC exists in multiple other forms, like edibles, capsules, suppositories, and topicals.

The dosing method chosen usually depends on preference, though some people may choose different THC products based on specific wellness needs.

For instance, suppositories may be recommended for chronically ill patients battling nausea or for managing pain from menstruation. Topicals may be the best way to target skin ailments that respond to THC, as studies have shown that there are plenty of endocannabinoid receptors in the skin.

Cannabis brands are constantly innovating new ways to take THC, and the expansive market offers a lot of opportunity to create a personalized dosing routine.

Still, with so many choices and very little regulation within the cannabis industry, it's incredibly important to vet brands and products carefully to avoid low-quality, contaminated products that could cause adverse reactions.

Does THC Have Any Side Effects?

Evidence regarding the potential side effects of THC use is shaky, and you can easily find reports that outline only mild effects, as well as reports that include a lengthy list of adverse reactions.

The most commonly discussed of these adverse effects is a condition called Cannabis Hyperemesis Syndrome, which may appear as repeated bouts of nausea and vomiting in people with a history of long term cannabis use. Evidence regarding what causes Cannabis Hyperemesis Syndrome or who may be most susceptible is limited, but adverse reactions generally stop after stopping cannabis use.

Additionally, there is some evidence that suggests that THC may cause anxiety and paranoia in some people. In some cases, research suggests that this is dose dependent, while other experts point to the differing cannabinoid and terpene levels in different strains to explain the varying effects of cannabis of anxiety.

Generally speaking, the most commonly reported side effects from THC use are red eyes, dry mouth, tiredness, and increased appetite.

Many sources suggest that CBD may offset some of the negative effects of THC, like paranoia. Choosing a cannabis stain with a high CBD content and moderate to low THC content may be one way to lower the risk of adverse reactions.

Is THC Safe?

THC’s safety profile is still mostly undefined, but experts agree that THC poses at least some minimal risks. For instance, driving or operating machinery while impaired (by any substance, including THC) is unsafe and illegal in most areas.

Frequent THC use is also associated with Marijuana Use Disorder, a condition that causes dependence on THC products. However, this condition is more common in those who begin using cannabis before the age of 18 due to incomplete brain development.

Still, THC is frequently described as posing less risk than many pharmaceuticals and street drugs with a high potential for overdose. Experts suggest that the risk of dying from cannabis alone is very low.

If THC is sought out for medical use, you should include the guidance of your doctor to ensure safety. Like with all substances, it’s important to use cannabis responsibly when used for recreational purposes.

Key Takeaways

Of over 100 cannabinoids found in the cannabis family of plants, THC is the most common. THC is the cannabinoid responsible for cannabis’ psychoactive effects.

THC causes the “high” sought after by recreational users, but also poses great potential for medicinal use. In many cases, THC may have less side effects or lower risk of dependence or death than commonly prescribed medications, like opiates.

Because of its multiple medicinal applications, there are a few cannabis-based and synthetic cannabinoid-based medications that have gained FDA approval. Even more cannabinoid-formulations based on THC are in clinical trial stages.

Even though THC has considerable potential for medicinal use, it’s still federally classified as a Schedule I illicit substance. This classification largely limits research efforts, which may be prohibiting us from learning more about THC’s potential as a medication for multiple chronic conditions and life-threatening illnesses.

Before THC can be explored to its full potential, laws regarding THC will need to be changed at a national level. There are several ongoing efforts to make these changes.

In general, many people can safely use THC, but it doesn’t come without risks. Like with all substances, you should always use THC legally and responsibly. For medicinal use, always seek the guidance of your doctor.


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  26. “Marinol”
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  32. “Injury and Death”

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