THC Oil: A Comprehensive Guide to Everything You Need to Know
THC oil is a concentrated extract derived from the cannabis plant, containing tetrahydrocannabinol (THC) — the primary psychoactive compound responsible for many of cannabis’s therapeutic effects. In medical contexts, THC oil is used to help manage conditions such as chronic pain, anxiety, and certain neurological disorders.
In the UK, THC oil can only be accessed legally via prescription through a specialist medical cannabis clinic, such as CB1 Medical. These prescriptions are carefully tailored based on individual needs and medical history, ensuring safe, regulated, and clinically appropriate use.
This guide explores everything you need to know about THC oil — from how it works and how long it lasts to how it’s taken, stored, and prescribed.
Contents
How to take THC oil
There are a few common ways to consume THC oil for medical purposes:
- Orally (under the tongue): Often referred to as sublingual administration. Place a few drops under your tongue and hold for 30 – 60 seconds before swallowing. This allows for quicker absorption.
- Capsules or pastilles: These offer a more discreet and controlled dosage method, commonly used in UK prescriptions.
- Mixed with food or drink: Some patients prefer to blend their oil with food, though this can lead to slower and less predictable effects.
Your clinician will guide you on how much to take and how often, based on your specific needs and treatment goals.
How long does THC oil last?
The effects of THC oil can vary depending on the dose, the method of consumption, and individual metabolism. Generally:
- Onset: 30 minutes to 2 hours (faster when taken under the tongue)
- Duration of effects: 4 to 8 hours
- In your system: THC may remain in the body for days or even weeks, depending on usage frequency and individual biology
Does THC oil expire?
Yes, THC oil has a shelf life. Most products come with an expiry date and should be stored in a cool, dark place to maintain potency. Signs of expired THC oil include changes in smell, taste, or colour.
What colour should THC oil be?
THC oil can vary in colour from light golden to dark amber. Colour is influenced by the extraction method and carrier oil. A dramatic change in colour may indicate degradation or spoilage.
Does THC oil get you high?
Yes, because THC is psychoactive, it can cause a “high.” However, when used medically and as prescribed, doses are often adjusted to balance symptom relief without unwanted psychoactive effects.
Is THC oil safe to consume?
When prescribed by a licensed clinic and used according to medical guidance, THC oil is generally considered safe. Common side effects include dry mouth, fatigue, dizziness, or mild anxiety — often managed by adjusting the dose.
What are the effects of THC oil?
Therapeutic effects of THC oil may include:
- Pain relief
- Reduced inflammation
- Improved sleep
- Muscle relaxation
- Mood elevation
These effects vary between individuals and depend on the condition being treated, the dosage, and the presence of other cannabinoids like CBD.
How long does THC stay in your body?
THC is fat-soluble, meaning it can stay in the body longer than many other substances. While the effects wear off after several hours, THC metabolites may remain detectable in urine, saliva, or blood for days or weeks depending on usage frequency.
Can THC oil go bad?
Yes. If stored improperly or past its expiry date, THC oil can degrade and lose effectiveness. Always check the label for storage instructions and expiry date.
How to take THC drops
If prescribed THC oil in drop form:
- Use the dropper to measure your dose accurately.
- Administer under the tongue for faster onset.
- Start low and go slow — especially if you’re new to THC.
What does THC oil do?
THC oil interacts with the endocannabinoid system to help regulate pain, mood, appetite, and inflammation. The exact benefits depend on the condition being treated and your body’s unique response to cannabinoids.
Learn more about THC oil and your health
At CB1 Medical, we support eligible patients across the UK with safe, regulated access to medical cannabis — including flower, oils, and capsules. All treatments are prescribed by specialists, and our team is here to guide you at every step.
Curious if you’re eligible?
Try our free eligibility checker to see if medical cannabis is right for you.
