CBD vs THC: Key Differences, Effects & UK Legal Status

Q: Is THC legal in the UK?

In short - no. THC is not legal for recreational use in the UK. However, it is legal for medical use with prescription, and it's also legal in CBD products when containing less than 0.2% THC.

September 17, 2025 · By Joseph Wilde

Last updated: September 2025

Quick Answer

CBD and THC are both cannabinoids from the cannabis plant, but CBD is non-psychoactive and won't get you "high," whilst THC is the compound responsible for cannabis's intoxicating effects. In the UK, CBD products with less than 0.2% THC are legal supplements, whilst THC remains a controlled substance requiring prescription. CBD may help with anxiety, inflammation, and sleep, whilst the use of THC is primarily reserved for severe medical conditions.

If you're exploring CBD to help you feel better naturally, you've probably wondered about the difference between CBD and THC. It's one of the most common questions we hear, and understanding the difference between CBD and THC is crucial for making informed decisions about your wellness journey.

Cannabis contains over 100 known cannabinoids, but two of them dominate both medical research and public conversation: CBD (cannabidiol) and THC (tetrahydrocannabinol). Whilst both come from the Cannabis sativa plant, their effects on your body and mind couldn't be more different. This comprehensive guide explores how CBD and THC interact with your body, their therapeutic potential, medical uses, and what current science tells us, all backed by reputable research.

Understanding the Effects of THC

THC is the primary psychoactive compound in cannabis, the one responsible for the "high" feeling often associated with marijuana use. THC works by directly activating CB1 receptors in your brain and central nervous system, which are part of the body's endocannabinoid system. This activation influences mood, memory, appetite, and pain sensation in ways that can be both therapeutic and intoxicating.

Medical Uses of THC

In the UK, the use of THC through medical cannabis is only available via specialist prescription for specific conditions. Medical professionals may prescribe THC products or medical cannabis containing higher concentrations of THC for:

Chronic pain relief, particularly in cases of neuropathic pain and cancer-related pain where other treatments have failed
Appetite stimulation in patients with AIDS or undergoing chemotherapy
Muscle spasticity in multiple sclerosis patients
Severe nausea and vomiting associated with cancer treatments

THC Side Effects to Consider

However, THC use comes with notable side effects that make it unsuitable for many people:

Anxiety or paranoia, especially at higher doses
Impaired memory and concentration
Increased heart rate
Potential psychotic symptoms in vulnerable individuals
Drowsiness and dizziness
Dry mouth and red eyes

These psychoactive effects are precisely why many people seeking natural wellness solutions prefer CBD products that help them feel better without the high. The amount of THC in a product dramatically affects both its effects and legal status.

Understanding the Effects of CBD

CBD takes a completely different approach compared to THC. It's non-psychoactive—meaning it won't get you "high" or impair your daily activities like THC does. Instead of directly activating cannabinoid receptors, CBD works more subtly with your endocannabinoid system and central nervous system. It helps preserve your body's own cannabinoids and interacts with serotonin and vanilloid receptors, which may explain why CBD may produce calming effects without intoxication.

Evidence-Based Benefits of CBD

Clinical research supports the therapeutic potential of CBD for several conditions:

Anxiety and stress management: Studies suggest CBD may help reduce anxiety symptoms and promote a sense of calm
Inflammation and pain: The effects of CBD on inflammatory and neuropathic pain conditions show promise
Epilepsy: The NHS (FDA in the U.S.) has approved Epidiolex, a CBD-based medicine, for certain rare forms of childhood epilepsy
Sleep quality: CBD may help improve sleep patterns and reduce insomnia
General wellbeing: Many users of CBD products report feeling more balanced and present in their daily lives

CBD's Safety Profile

CBD is generally well-tolerated with a much milder side effect profile than THC. The World Health Organisation (WHO) has stated that CBD exhibits no effects indicative of abuse or dependence potential and is generally well-tolerated with a good safety profile. The most commonly reported effects include:

Mild fatigue (often welcomed by those using it for sleep)
Changes in appetite
Dry mouth
Potential interactions with certain medications

This excellent safety profile is why CBD oil has become a popular choice for those looking to feel better naturally. At Unspun, our broad-spectrum CBD oils are completely THC-free and third-party tested, ensuring you get all the potential benefits of CBD without any psychoactive effects or concerns about drug testing.

CBD and THC: Do They Work Better Together?

An important concept in cannabis medicine is the "entourage effect"—the theory that THC and CBD may be more effective when working together than in isolation. Research indicates that certain combinations of CBD and THC might enhance pain management beyond what either compound achieves alone, particularly for chronic or treatment-resistant conditions.

However, recent research published in Nature found that CBD doesn't necessarily reduce the effects of THC or cognitive impairments as previously hoped. This finding reinforces that CBD and THC interact with the brain through different, complex pathways.

For those seeking the potential benefits of the entourage effect without THC's psychoactive properties, broad-spectrum cannabis products offer a middle ground. These formulations contain multiple cannabinoids from hemp and terpenes whilst remaining completely THC-free.

Legal and Regulatory Distinctions in the UK

The legal landscape for CBD vs THC in the UK is clear but often misunderstood:

CBD Legal Status

CBD products derived from hemp with less than 0.2% THC are legal as food supplements
Must comply with FSA (Food Standards Agency) Novel Food regulations
Available without prescription from reputable retailers
Cannabis products containing CBD must not make medical claims

THC Legal Status

THC products are classified as Class B controlled substances
Only available through specialist medical cannabis prescription
Possession of THC products without prescription is illegal
Medical cannabis clinics operate under strict regulations

This legal framework is why choosing CBD or THC depends largely on your circumstances. For most UK consumers, THC-free CBD products provide legal access to potential wellness benefits. Our products undergo rigorous testing to ensure they contain no detectable THC whilst maintaining the beneficial compounds that may help you feel better.

Therapeutic Potential: CBD vs THC Direct Comparison

Effect/Use	CBD	THC
Psychoactive	No	Yes
Pain Relief	Moderate effect, especially for inflammation	Strong effect, particularly for severe pain
Anxiety	May reduce anxiety	THC is often reported to increase anxiety
Appetite	Minor effect	Significant increase
Sleep Aid	Gentle support	Strong sedation
Anti-seizure	Approved medical use	Not typically used
Inflammation	Promising research	Some evidence
UK Legal Status	Over-the-counter supplement	Prescription only
Side Effects	Mild and rare	Can be intense
Drug Testing	THC-free CBD products won't trigger positive results	Will show on drug tests

Choosing Between CBD and THC: Making the Right Decision

When deciding between CBD or THC, consider your specific needs, lifestyle, and comfort level:

CBD May Be Ideal If You:

Want the benefits of CBD without psychoactive effects
Need to maintain clarity for work or daily responsibilities
Are concerned about drug testing
Seek gentle, natural support for stress and sleep
Prefer over-the-counter accessibility
Want to incorporate wellness support into your daily routine using cannabis-derived products

THC May Be Appropriate If You:

Have severe, treatment-resistant pain
Are under specialist medical care
Have conditions specifically responsive to THC
Can manage the psychoactive effects
Have legal access through prescription

For many people in the UK using cannabis products, high-quality, THC-free CBD oil offers the perfect balance—providing potential wellness benefits whilst remaining legal, non-intoxicating, and suitable for daily use.

Quality Matters: What to Look for in CBD Products

Not all CBD products are created equal. When choosing CBD to support your wellness journey, consider these crucial factors:

THC-free formulation: Ensures no psychoactive effects or drug test concerns
Third-party testing: Verifies purity and potency
Extraction method: CO2 extraction preserves beneficial compounds without chemical solvents. Cold-pressed retains raw cannabinoids like CBG and CBDA but yields less concentrated CBD. Ethanol is cheaper and common in mass-market products—safe but can affect taste if not done properly
Hemp source: EU-grown hemp meets strict quality standards
Transparency: Reputable brands provide full lab reports

These standards guide everything we do at Unspun, from sourcing EU-grown hemp to using both supercritical CO2 extraction and cold-pressed methods, ensuring you receive products that truly help you feel better.

Frequently Asked Questions

Is THC legal in the UK?

In short - no.

No for recreational use.
Yes for medial use (with prescription).
Yes in CBD (when containing less than 0.2% THC).

Is CBD legal in the UK?

Yes, CBD is legal in the UK when derived from approved hemp strains containing less than 0.2% THC. Products must comply with FSA Novel Food regulations and cannot make medical claims. Always purchase from reputable suppliers who provide third-party lab reports.

Will CBD show up on a drug test?

Pure CBD shouldn't show on a drug test, but some cannabis products may contain trace amounts of THC that could trigger a positive result. This is why choosing genuinely THC-free, broad-spectrum CBD products with verified lab testing is essential for those subject to drug testing.

Can I take CBD with other medications?

CBD can interact with certain medications, particularly those metabolised by liver enzymes. Always consult your GP or pharmacist before adding CBD to your routine if you take prescription medications, especially blood thinners, heart medications, or anti-seizure drugs.

How long does CBD take to work?

The onset time varies by delivery method. Sublingual oils typically work within 15-45 minutes, whilst edibles like CBD gummies may take 30-120 minutes. Effects generally last 4-6 hours. Consistent daily use often provides the best results for overall wellbeing.

What's the difference between broad-spectrum and full-spectrum CBD?

Full-spectrum CBD contains all cannabis compounds including trace amounts of THC (up to 0.2% in the UK). Broad-spectrum CBD contains multiple cannabinoids and terpenes but with THC completely removed. Broad-spectrum offers potential entourage benefits without THC concerns.

Can CBD help with anxiety?

Research suggests the therapeutic potential of CBD may help manage anxiety symptoms. Many users report feeling calmer and more balanced with regular use of CBD. However, CBD is a supplement, not a medicine, and shouldn't replace prescribed anxiety treatments. Always discuss anxiety management with your healthcare provider.

What's the recommended CBD dosage?

CBD dosage is highly individual, depending on factors like body weight, metabolism, and desired effects. Most people start with 10-20mg daily and gradually increase until they find their optimal dose. Our dosage calculator can help you find a starting point.

The Bottom Line: Finding What Works for You

Understanding the difference between CBD and THC empowers you to make informed decisions about your wellness journey. Whilst the use of THC remains an important medical tool for specific conditions under professional supervision, CBD offers a gentler, more accessible option for those seeking to feel better naturally.

The key differences to remember:

CBD is non-psychoactive and legal; THC causes intoxication and requires prescription
CBD suits daily wellness support; THC is reserved for specific medical conditions
CBD has minimal side effects; THC can cause significant psychoactive effects
CBD won't affect drug tests (when THC-free); THC will show positive results

As research continues to unveil the complexities of cannabinoids, one thing remains clear: quality, transparency, and informed choice matter. Whether you're exploring CBD for the first time or looking to optimise your wellness routine, choosing reputable, THC-free products ensures you can pursue feeling better with confidence and peace of mind.

Ready to explore how CBD might fit into your wellness journey? Browse our range of third-party tested, THC-free CBD products or read more about finding the right CBD product for your needs.

Medical Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare provider before starting any new supplement regimen. CBD products are not suitable for under 18s. CBD food supplements are not intended to diagnose, treat, cure, or prevent any disease.

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