What is THC (Tetrahydrocannabinol)?

13/05/2025
THC - Tetrahydrocannabinol

THC, or tetrahydrocannabinol, is the principal psychoactive compound found in the cannabis plant, responsible for producing the sensation commonly referred to as being 'high'. As interest in cannabis continues to grow — whether for medicinal research or recreational use — understanding the role of THC is essential.

It is important to recognise, however, that THC is only one of over 100 cannabinoids identified within the complex chemical structure of the cannabis plant.

Having dedicated more than a decade to the cannabis industry, particularly in the fields of CBD and hemp production, I have witnessed first-hand the significant advancements in scientific understanding and public awareness surrounding cannabinoids.

This growing body of knowledge underscores the importance of examining THC not solely for its psychoactive properties, but also for its wider significance within cannabis science and its potential applications across various sectors.

Prefer watching over reading? This video covers the key points from the article:

Key takeaways

  • THC is the primary psychoactive compound in the cannabis plant, inducing the 'high' sensation.
  • It is one of over 100 cannabinoids present within cannabis and marijuana, highlighting the plant's complexity.
  • THC's effects include mood alterations, impaired memory and motor skills, and altered sense of time.
  • Research continues into THC's broader scientific and botanical properties.

This article is provided for informational purposes only and does not relate to any of the products available in our webshop. For more information, please see our full disclaimer.

Dr. Rapahel Mechoulam
Mechoulam delivering a lecture with the structure of Tetrahydrocannabinol displayed behind him, circa 1964. Image courtesy of Zach Klein, from his documentary "The Scientist".

Introduction to THC

The story of THC discovery begins in the 1960s when the compound was first isolated and synthesised. This groundbreaking achievement accelerated our understanding of the psychoactive effects of cannabis plants. It paved the way for decades of research into the properties and potential applications of this prominent cannabinoid.

Background and discovery

Israeli scientist Dr. Raphael Mechoulam first isolated THC in 1964, revolutionising the way researchers viewed and studied cannabis plants. This marked a critical advancement in decoding the cannabinoids responsible for the 'high' sensation individuals experience when using cannabis.

The history of THC

Since then, THC has remained a primary focus for researchers studying its psychoactive properties and broader biological interactions.

The past few decades have witnessed significant strides in understanding the complexities of THC and its interactions with the human body, altering mood, perception, and physiological processes. These discoveries have fuelled ongoing scientific research into THC's properties and interactions with biological systems.

The chemical structure of THC

THC, scientifically known as delta-9-tetrahydrocannabinol, is unique in its molecular composition. The compound's chemical structure highly binds it to the brain's CB1 receptors, accounting for the ensuing psychoactive effects.

When THC interacts with the endogenous cannabinoid system, a series of events unfolds, compromising mood, perception, and various physiological processes.

THC molecular image

"The chemical structure of THC enables it to bind powerfully to the brain's CB1 receptors, triggering the psychoactive effects characteristic of cannabis."

Find your CBD oil with less than 0.2% THC today

Comparing THC with other cannabinoids

Among the many known cannabinoids, THC and CBD (cannabidiol) have attracted the most attention in scientific research. The following table highlights the primary differences between these two compounds.

Property THC CBD
Psychoactivity Yes No
CB1 receptor affinity High Low
Mood and perception alteration Significant Minimal

Synthetic THC-based medicines have been developed under regulated medical programmes. Their use is strictly controlled and varies by jurisdiction.

THC and the endocannabinoid system

Tetrahydrocannabinol (THC) interacts with the body through the endocannabinoid system (ECS), a complex cell-signalling network present in humans and many animals. The ECS plays a role in regulating various physiological processes, and it includes cannabinoid receptors (CB1 and CB2), endocannabinoids naturally produced by the body, and enzymes that break them down.

THC primarily binds to CB1 receptors, which are highly concentrated in areas of the brain associated with memory, mood, perception, and coordination. This binding process alters the usual signalling patterns of the ECS, leading to changes in how information is processed within the nervous system. THC’s strong affinity for CB1 receptors is the main reason for the compound’s psychoactive properties.

While CB2 receptors are more commonly found in immune-related tissues, THC also interacts with these receptors to a lesser extent. Its interaction across the ECS can influence a range of responses in the body, depending on factors such as concentration, method of use, and individual variation in ECS activity.

What is endocannabinoid system?

THC and CBD: Key differences

THC (tetrahydrocannabinol) and CBD (cannabidiol) are two primary cannabinoids naturally occurring in the cannabis plant. While both originate from the same plant species, Cannabis sativa, they differ notably in their chemical structures.

THC binds directly to CB1 receptors in the brain and nervous system, leading to its psychoactive effects. CBD, however, interacts differently, influencing receptor activity without causing psychoactive sensations.

What is CBD?

differences between THC and CBD

Psychoactive vs. non-psychoactive

One of the most significant differences between THC and CBD is their psychoactive properties. THC is known for producing psychoactive effects, which may alter mood, sensory perception, and cognition.

In contrast, CBD is non-psychoactive, meaning it does not cause alterations in consciousness or sensory perception. This makes CBD appealing to individuals who prefer to avoid psychoactive experiences.

Applications and usage

THC and CBD differ considerably in their common applications. THC is primarily associated with recreational cannabis use, where psychoactivity is desired.

CBD, conversely, is predominantly used in cosmetic industries due to its non-psychoactive profile. CBD products range widely from topical creams to cosmetics, making them accessible to broader consumer groups.

Product availability and forms

Products containing THC are typically restricted to regions where cannabis use is permitted, often through specialised dispensaries or dedicated outlets. In contrast, CBD products have a broader presence, appearing in items such as cosmetics, topicals, skincare, and wellness goods, and are commonly sold both online and in physical retail stores.

Browse CBD oils with less than 0.2% THC

The adverse effects of THC

Scientific research into THC has explored its diverse properties across a range of biological systems. However, it remains important to be aware of the potential adverse effects and risks associated with its use.

The side effects of THC can be both psychological and physiological, with their severity varying depending on the individual and the level of exposure to the psychoactive compound.Adverse Effects of THCScientific studies have explored the potential impact of THC on mental well-being, suggesting that some individuals may experience heightened alertness, unease, or anxiety, particularly those with a predisposition to such conditions (e.g., Crippa et al., 2009; Freeman et al., 2015). These responses tend to vary based on individual sensitivity, dosage, and environmental factors.

Research also indicates that higher levels of THC may be associated with short-term cognitive effects, including difficulties with memory, attention, and motor coordination (Curran et al., 2002; Broyd et al., 2016). In rare cases and typically at higher doses, altered sensory perception—such as unusual thoughts or feelings—has been reported, especially among individuals with existing mental health vulnerabilities (Murray et al., 2017).

These observations are based on controlled clinical studies and self-reported data and do not reflect effects experienced by all users.

Extraction methods and solvent removal techniques

In cannabis extraction processes, various methods are used to remove solvents and isolate key compounds such as THC. Each technique offers distinct advantages and challenges, depending on the desired purity and application.

  • Chromatography: to separate individual cannabinoids and other compounds.
  • Crystallisation: to isolate and collect pure THC crystals.
  • Final stages: like decarboxylation, activate the psychoactive properties of the THC.

The final product is a high-quality, pharmaceutical-grade THC that can be further processed for use for its potential in various medical treatments and formulations.

Extraction method Pros Cons
CO2 extraction Clean, efficient, high-quality result Requires specialised equipment, can be expensive
Solvent extraction Relatively simple process, inexpensive May require additional purification to remove residual solvents
Steam distillation No solvents needed, scalable process Lower efficiency, potential for heat damage
Cold press extraction Minimal impact on compounds, no residual solvents Lower yield may require further purification

The future of THC

As cannabinoid research develops, our understanding of THC and its various properties grows too. Upcoming trends and developments in the field include a wider range of medicinal uses, a deeper understanding of pharmacogenomic interactions, and a progression in legal regulations that could ultimately lead to increased accessibility and acceptance of THC-based treatments.

Ongoing research into THC’s broader properties may uncover new areas of scientific interest, expanding our understanding of its role within cannabinoid studies.

The Future of THC

Formula Swiss continues to invest in cannabinoid research, with a particular focus on advancing our understanding of compounds like THC through organic cultivation practices and scientific study.

Alongside these discoveries, researchers are delving into the intricacies of pharmacogenomic interactions, which involve understanding the individual's genetic response to THC and tailoring treatment accordingly. 

This personalised approaches may contribute to future research into individual responses to cannabinoids while minimising unwanted side effects and adverse reactions.

Legal developments in many parts of the world are gradually shifting towards a more accepting stance on THC and its medical potential, with several countries altering their regulations in favour of allowing access to cannabinoid-based treatments.

These advancements provide hope for both patients and researchers alike, as they signal a more profound recognition of the latent opportunities within the realm of cannabinoid science.

Personal perspective

After years of studying cannabinoids, I consistently return to THC as one of the most significant. Its discovery by Dr Raphael Mechoulam in the 1960s transformed our understanding of cannabis and sparked decades of scientific exploration.

What draws me most is how THC interacts with the endocannabinoid system, particularly with CB1 receptors in the brain, highlighting the close relationship between plant compounds and human biology.

In my years of experience, the differences between THC and CBD are clear — not only in their chemical structures but also in how they interact with biological systems. THC’s strong affinity for CB1 receptors helps explain its association with psychoactive experiences, while CBD engages through different mechanisms.

For me, this demonstrates why careful, evidence-based research into cannabinoids remains essential for shaping the future of cannabis science and regulation.

At Formula Swiss, we are committed to advancing cannabinoid research through organic farming methods and evidence-based study. This approach ensures that our knowledge of compounds such as THC continues to develop in line with the highest standards of quality, transparency, and scientific integrity.

View our collection of CBD oils with less 0.2% THC here

Frequently asked questions


What is THC?

THC, scientifically known as tetrahydrocannabinol, is the primary psychoactive compound found in cannabis plants. It interacts with receptors in the brain and nervous system, producing the characteristic euphoric sensation often referred to as the "high."

What are the side effects of THC?

The side effects associated with THC use can include dry mouth due to reduced saliva production, heightened heart rate, temporary redness in the eyes, impaired short-term memory and concentration, and for some individuals, heightened anxiety or paranoia.

How long does THC stay in your system?

THC's duration in the body can last up to 30 days, contingent upon several factors including frequency of use, dosage, metabolism rate, and the type of test used to detect it in bodily fluids.

Is THC addictive?

Yes, THC has addictive potential, especially with frequent and heavy use. It can influence the brain's reward system, leading to dependence and withdrawal symptoms upon cessation.

Can you overdose on THC?

While overdosing on THC to the point of fatality is highly unlikely, using excessive amounts can induce intense and uncomfortable symptoms such as severe anxiety, paranoia, and hallucinations, which can be distressing but typically subside without causing long-term harm.

What is the difference between THC and CBD?

THC and CBD are both compounds found in cannabis; however, while THC is psychoactive, altering perception and cognition, CBD is non-psychoactive and is widely studied for its properties without inducing a "high."

Can THC show up on a drug test?

Yes, THC can be detected in drug screenings for a considerable duration after use, potentially showing up in urine, blood, saliva, or hair tests, depending on the timeframe and sensitivity of the test employed.

What is CBD?


Back to blog

Leave a comment

Please note, comments need to be approved before they are published.

Robin Roy Krigslund-Hansen

Robin Roy Krigslund-Hansen

About the author:

Robin Roy Krigslund-Hansen is known for his extensive knowledge and expertise in the fields of CBD and hemp production. With a career spanning over a decade in the cannabis industry, he has dedicated his life to understanding the intricacies of these plants and their potential benefits to human health and the environment. Over the years, Robin has worked tirelessly to promote the full legalisation of hemp in Europe. His fascination with the plant's versatility and potential for sustainable production led him to pursue a career in the field.

More about Robin Roy Krigslund-Hansen

Related products

1 of 3