You’ve likely heard that cannabis lowers eye pressure.
But does that mean it helps with glaucoma?
Some patients ask about using it instead of eye drops.
Others wonder if it works better than surgery.
Let’s clear it up with what eye doctors actually say.
Where the Idea Started
In the 1970s, studies showed something interesting.
Cannabis temporarily reduced intraocular pressure (IOP).
This is the main target in treating glaucoma.
That got attention.
But there’s more to the story.
What Does Cannabis Do?
Yes, it lowers IOP.
But only for a short time—about 3 to 4 hours.
To keep IOP low 24/7, you’d need to use it 6 to 8 times a day.
That’s not practical or safe.
The form of cannabis matters too.
Smoking is the most studied method—but it comes with health risks.
What Doctors See in Clinics
Eye specialists don’t recommend cannabis as a main treatment.
Why?
Short duration of action
Risk of addiction or mental fog
Lack of consistent dosing
Safer and longer-lasting treatments already exist
Doctors worry patients will skip proven methods.
That could lead to nerve damage and vision loss.
Can You Use It With Drops?
Some patients ask if they can use cannabis with prescription drops.
Doctors say it’s not necessary.
Eye drops last longer and work better.
Combining them doesn’t lead to extra benefit.
It may also complicate how your care is managed.
What About CBD?
Many products today contain CBD (cannabidiol).
Unlike THC, CBD doesn’t cause a “high.”
But studies show CBD might raise IOP in some cases.
That’s the opposite of what glaucoma patients need.
You should tell your doctor if you use CBD.
It may change how your eyes respond to treatment.
Legal Doesn’t Mean Safe
Cannabis is legal in some places.
That doesn’t make it the best choice for eye care.
Doctors base treatment on evidence.
They look at how long a drug works, how strong it is, and its side effects.
Cannabis doesn’t meet the standards for long-term IOP control.
Ask These Questions Before Trying It
Does it replace my prescribed drops or surgery?
(No.)Will it protect my optic nerve?
(No proven benefit.)Could it interact with my current medication?
(Possibly.)Am I using it because I don’t trust my treatment?
(Talk to your doctor.)
What Glaucoma Needs
You need consistent eye pressure control.
All day.
Every day.
That’s how you prevent nerve damage.
It’s how you protect vision.
Cannabis, on its own, can’t do that.
What the Studies Show
Here’s what the research says:
THC lowers IOP for a few hours
CBD may raise IOP
No form of cannabis provides lasting control
No clinical trial recommends it as first-line care
Safer, stronger drugs already exist
The science doesn’t support replacing your treatment with cannabis.
What to Tell Your Eye Doctor
If you use cannabis, say so.
Be honest.
Your doctor won’t judge.
But they need to know everything that could affect your treatment.
Ask:
Is my current treatment working?
Do I need to adjust anything?
Should I get more nerve imaging done?
Are there clinical trials I can join?
Where Research May Go
Some labs are working on cannabis-based drugs.
The goal is to make them longer-acting, safer, and more targeted.
That’s years away.
But it shows that the medical field is paying attention.
Until then, stick to what works.
Final Thought
You want to protect your vision.
That means using treatments that keep pressure stable.
Cannabis has short-term effects.
But it can’t replace proven methods.
Talk to your doctor.
Stay on your plan.
Don’t gamble with your sight.
