8 min read
Leanne Hall
Delta 9 Tetrahydrocannabinol (THC) is the most abundant cannabinoid in the cannabis plant. It is the main ingredient that patients are looking to benefit from when accessing medical cannabis products through private prescriptions available in the UK.
Key takeaways
Contents
THC oil is made by extracting cannabinoids, mainly THC, from the flower of the cannabis plant and dissolving them into a carrier oil that can then be consumed under the tongue. It usually takes 1 to 1.5 hours to work and lasts 6 to 8 hours. THC oil comes in two main forms, full-spectrum, which keeps other cannabinoids and terpenes from the plant and isolate, which contains THC on its own.
THC oil can have psychoactive effects while CBD oil doesn’t cause a high. CBD oil can be bought over the counter in the UK if it contains no more than 1 mg of each controlled cannabinoid per container, while THC oil is only legal when prescribed by a specialist doctor. Find out more about how THC oil differs from CBD oil, or find out more about the different types in our guide, cannabis oil fully explained.
THC has been studied quite thoroughly since the 1960s. Cannabis is the subject of tens of thousands of research papers, and research into the exact therapeutic benefits that THC may offer is still underway, but there have been significant papers published looking into the relationship between both THC and major health conditions, and also the functional systems within the human body.
The chances of fatally overdosing on cannabis are slim, but one of the main issues is that not enough research has been done to determine the potential long-term effects of medical cannabis.
Cannabinoids, like THC, mimic naturally occurring neurotransmitters that everyone has inside of them. THC interacts similarly to one called anandamide, named after the Sanskrit word for “bliss”. These neurotransmitters send different messages at different points around the body to carry out specific biological tasks and functions.
The name for these specific neurotransmitters that are similar to ones found in cannabis are called endocannabinoids. Both our own endocannabinoids, and the (phyto) cannabinoids produce by cannabis, bind at cannabinoid receptor sites. THC and Anandamide have a high affinity for binding to the receptor dubbed CB1. Endocannabinoids act on the endocannabinoid system, which helps regulate many processes in the body. This advanced network evolved in humans' ancestors around 550 million years ago, and is found in all other animals.
As you can see, humans have a biological system that is capable of processing different cannabinoids. It is thought that cannabis was one of the first three crops to be domesticated by humans and cultivated on an agricultural scale. In fact, the world's oldest medical books and pharmacopoeias dating back nearly 6,000 years list cannabis as an essential medicine. From Ancient Greece to China, many of the medical conditions that cannabis is prescribed for now were documented as being treated with cannabis.
Cannabis oil as a medicine offers potential symptom relief for a wide range of health issues, including chronic pain, nausea and vomiting caused by chemotherapy, and muscle spasticity in multiple sclerosis.
Besides the actual symptom relief that THC provides to patients, other positive side effects that have been reported are improved sleep, appetite, mobility, mood and stress levels. A UK study of 2,833 patients prescribed medical cannabis reported improvements in their quality of life, anxiety and sleep over 12 months of treatment. These findings are based on the patients’ own reports and responses varied person to person.
Many patients report that they do not feel the traditional high associated with THC when using THC oil at the prescribed dose. The idea behind administering THC oil for symptomatic relief isn't to feel the intoxicating effects, but to unlock the potential therapeutic benefits. This may be done at lower doses than required for intoxication. Some patients report that they feel more able to get on with daily tasks and activities than they would if they weren’t fighting the symptoms of a medical condition.
Some patients report not having the most enjoyable first experience with THC oil, and this can be normal – especially if they have never taken cannabis before. There are ways to go about trying to improve the chances of not having a negative experience.
Make sure you are in a safe environment and enjoyable setting. It is never recommended that new patients take THC oil for the first time in a place that they are uncomfortable or unfamiliar with. Some people report feeling disoriented when they first administer THC oil, and being somewhere that is familiar can be of huge benefit.
THC can cause your blood glucose levels to drop quite rapidly, so if you are diabetic, you should definitely monitor your glucose levels. It is also advised that you have someone with you that you are comfortable with.
Too much THC can result in dizziness, spinning feelings, nausea, vomiting, uncontrollable giggles, racing thoughts, hallucinations, memory loss, confusion, extreme hunger, dry mouth, fatigue, lethargy, loss of balance, reduced ability to communicate, and general confusion. It is important to remember that all of these symptoms will usually ease within six to eight hours, but residual effects may last several days. If you take a high dose of THC just before bed, you may wake up feeling groggy, and that feeling can last for the entire next day.
In the worst of cases, THC oil can induce tachycardia, increase cardiac labour, systemic vasodilation, and an increase in blood pressure. There can be more severe effects in people who already have an existing heart condition, and it is advised not to take THC based medications in these instances. Angina, myocardial infarction, cardiac death, and cardiomyopathy are at greater risk when taking THC if you have pre-existing cardiovascular conditions.
If you are taking other medications as well as THC, it is always recommended that you check with your prescribing doctor to ensure there will be no negative interactions.
Medications that interact with the P450 cytochrome will have a possible interaction with THC and CBD. THC is also metabolised by the liver enzyme CYP2C9 and inhibitors of this enzyme such as fluoxetine, cotrimoxazole, and amiodarone can increase the psychoactive effects of THC. Other similar effects may be noticed with CYP3A4 inhibitors like macrolides and verapamil. Anyone with diabetes should talk to their specialist and diabetes team before starting medical cannabis treatment.
If you have found yourself taking too much THC, there are a few things you can do to help reduce the negative side effects.
To help alleviate side effects, stay hydrated and eat a light snack. You should contact your clinician about the side effects.
You can also contact NHS 111 for advice or 999 in an emergency.
Just remember, this won’t happen every time you take THC oil, your body just needs to adjust to it. Starting on a low dose and gradually building up, a process known as titration, is the best way to go about introducing THC oil as a medicine.
CBD oil may also be an aid in reducing the unwanted side effects of THC oil.
Your medical cannabis dosage will be set by your specialist doctor and should always be followed, read our guide on how to take THC oil.
THC oil may be a beneficial medicinal option to help treat many conditions and symptoms. It is important to ensure that the correct dose is taken, and that any pharmaceutical drugs you are taking do not interact with THC, before you begin treatment. Also note that it is possible to take too much THC oil, which can result in unwanted side effects. However, starting off on a low dose and slowly increasing to the prescribed dosage level will help to reduce the risk of having a negative experience.
If medicinal cannabis is of interest to you, reach out to us here at Releaf. We offer an all-in-one medical cannabis platform to help you understand the effects, benefits and potential risks of using THC oil for symptom relief.
THC oil can cause side effects, most reported are mild to moderate, and it isn't suitable for everyone. Those on other medications must check if medical cannabis treatment will interact with their current prescriptions, as well as those with diabetes, people breastfeeding, trying to conceive, or who are pregnant. Some mental health conditions may also not benefit from using medical cannabis that contains THC.
THC oil is only legal when it has been prescribed by a specialist doctor in the UK. It has been legal to prescribe as part of a medical cannabis treatment since November 2018.
Your specialist doctor will decide whether any THC and/or CBD medical cannabis is the right fit for you.
It is important to seek medical advice before starting any new treatments. The patient advisors at Releaf are available to provide expert advice and support. Alternatively, click here to book a consultation with one of our specialist doctors.
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