CBD has gained widespread, mainstream popularity in the past few years. User experiences are one of the main contributions to its popularity as studies are limited and nonclinical.
This article will focus on CBD’s effects on glaucoma. We will also cover what CBD is and eliminate the most common misunderstandings and misconceptions that surround the substance.
Can CBD help with glaucoma? No CBD does not help glaucoma. Warnings and studies have been published stating and showing that CBD could actually worsen glaucoma by increasing intraocular pressure (IOP).
This 2006 study found that THC can help to reduce IOP but CBD actually increases IOP. High IOP is one of the factors that are present with glaucoma.
Many variables have to be considered with CBD because it depends on the product, the quality of it and how some people metabolize CBD differently, just as with any biohacking supplement.
What is CBD?
Cannabidiol oil (CBD) is extracted from the leaves, stalks, and flowers of industrial hemp plants. CBD is a cannabinoid, these are compounds found in the cannabis plant species. Unlike the similarly prominent cannabinoid, THC, CBD is non-psychoactive meaning it does not produce a ‘high’.
THC is the main psychoactive compound found in the cannabis plant species, it is responsible for the ‘high’ that cannabis gives you.
What is Glaucoma?
Glaucoma is one of the most common reasons for blindness. It is a condition where the optic nerve (which connects the eye to the brain) is damaged.
Often is caused by a buildup of fluid in the front of the eye, this increases pressure in the eye.
To begin with, glaucoma does not produce any side effects or symptoms. It usually develops over a period of a few years, reducing your peripheral vision first. This is the reason why it is most commonly found in routine eye tests rather than being diagnosed or noticed by the sufferers themselves.
If there are symptoms they could include blurred vision or seeing rainbow-colored circles around bright lights.
There are four main types of glaucoma, these are:
- Primary open-angle glaucoma – developed over many years, caused by the drainage channels in the eye eventually becoming clogged.
- Acute angle-closure glaucoma – also caused by the drainage in the eye becoming blocked however, in this case, suddenly blocked. This causes a rise in pressure inside the eye very quickly
- Secondary glaucoma – caused by another eye condition, such as inflammation of the eye (uveitis)
- Childhood glaucoma (congenital glaucoma) – occurs in very young children, caused by an abnormality of the eye
Reversal of any loss of vision that happened before being diagnosed with glaucoma is impossible. Treatment is aimed at helping to stop vision from getting worse. Treatment and medicines include:
- Eye drops – these reduce pressure in the eyes
- Laser treatment – opens up the blocked drainage tubes
- Surgery – can help to improve the drainage of fluid
How does CBD affect Glaucoma?
It was previously thought that CBD could help to relieve glaucoma due to its anti-inflammatory properties.
However, recent studies have found that it could aid in the worsening of the condition rather than helping.
A 2018 study on rats found that a CBD eyedrop increased pressure inside the eyes by 18% for around four hours after the drops were administered.
On the other hand, positively, CBD’s cannabinoid counterpart THC, which is responsible for the high that marijuana gives you, was found to reduce eye pressure by up to 30% in eight hours.
The afore referenced 2006 study also evidenced that CBD’s counterpart, THC, could help to reduce eye pressure.
Studies on cannabinoids and eye conditions continue on. However, CBD is likely to be left in the lurch in the ocular area of research with more and more studies finding the same, negative, results. Its cannabinoid counterparts – including THC – however, are being shown to help with eye pressure and therefore glaucoma.
CBD forms and dosage
CBD comes in a variety of forms, these include:
- Oil in sprays and tinctures
- Vaporizers/vape oils
- Infused water
- Infused coffee
- Shower gels/bath bombs/bath salts and shampoos
Dosing for CBD doesn’t really matter for glaucoma as we can’t recommend using it for treatment with what research and studies have found.
Misconceptions surrounding CBD
Does CBD get you high?
CBD does not get you high. Legal CBD extracted from industrial hemp plants are legally required to contain less than 0.2 % in the UK, and 0.3% in the US, THC content. This amount is insignificant and presents no risk of getting ‘high’ from taking any CBD products.
Legality of CBD
In Canada, CBD along with recreational marijuana use is legal, however individual provinces have their own laws so check here for a more detailed outline on the legality of CBD in Canada.
CBD products from Canada may contain more than the legal amount of THC (as there is no limit) than other countries allow, so be cautious in transporting or trying to import CBD products from Canada.
In the United States, some states have legalized recreational marijuana use while some outlaw CBD as they do not differ it from marijuana itself, check here for a state by state guide on the legality of CBD in the US.
In federal law, CBD is legal so long as it is extracted from industrial hemp plants and contains less than 0.3% THC content.
In the United Kingdom CBD is legal as long as it is extracted from industrial hemp plants and contains less than 0.2% THC content.
In Australia, CBD and other ‘medicinal cannabis’ products can only be prescribed by a registered medical practitioner following an in-depth assessment of the patient’s condition and individual, outside circumstances.
Side effects and risks of CBD
Side effects of CBD are largely uncommon and insignificant. Short term side effects include:
- Tiredness + mood changes
- Appetite change
Long term side effects are unstudied as studies have only recently begun on CBD.
Failing a drug test because of CBD
Drug tests look for THC and its metabolites.
Because CBD contains trace amounts of THC a false positive can result from taking CBD so be cautious when taking CBD before a drug test. Both the Hemp and Marijuana plant, which CBD can be derived from, contain THC.
Industrial Hemp is legal because the amount of THC is limited to 0.2 – 0.3%, where Marijuana plants have no limit, which is why the plant is illegal.
CBD can interfere with your body’s ability to process certain pharmaceutical drugs; specifically, it inhibits cytochrome p450. As with some other medications, CBD is metabolized in the body by the enzymes in the CYP450 system.
So, in competing for these enzymes, CBD can reduce the metabolism of other drugs, raising their blood levels and having the inhibitor effect described above.
This means that lower dosages are more likely to be required without knowing so. This could lead to the potentially harmful levels suggested above.
Clinical trials have shown this where CBD is provided in hundreds of milligrams (mg) daily. The average CBD supplement pill can range from 10 to 40 mg, therefore the effect may not be as strong in smaller doses of CBD.
Drugs that are affected by grapefruit do have warnings so watch out for these and avoid CBD when seeing this warning.
Unfortunately, more and more studies are showing that CBD cannot help with glaucoma and could potentially worsen the condition.
Therefore, we cannot recommend that you try CBD when trying to relieve or slow down the progression of glaucoma.
Instead, consult your doctor about medical marijuana products that contain THC but not CBD, as THC is being shown to help with eye pressure.