Red eyes can have many causes, making it challenging to identify the problem without an eye exam. If your eyes are red, consider what you’ve been exposed to recently. If you’ve used cannabis, that might be the cause. 

It’s generally common knowledge that smoking cannabis leads to red eyes. However, cannabis is consumable in many ways, so you may wonder if edibles can make your eyes red. 

Do Edibles Make Your Eyes Red?

Yes, edibles can make your eyes red, if they contain THC. It doesn’t matter how THC gets into your body. Whether through a vape, joint, drink, edible, or other smoking apparatus, cannabis will make your eyes red if it has THC (delta-9-tetrahydrocannabinol). 

Redness happens because of the effect THC has on your eyes. THC is a cannabinoid that gives you the “high” you feel when you consume cannabis. It also affects your blood vessels, making your eyes red. 

Ingesting THC lowers your blood pressure, which dilates your blood vessels. This dilation increases blood flow throughout your body, including your eyes. The blood vessels in the eye enlarge, becoming red for a short period. 

Eye redness is temporary, going away with time. 

How Does Cannabis Affect Your Eyes & Eye Health? 

Besides red eyes (and maybe the giggles), cannabis lowers eye pressure. Because of this, some people wonder if cannabis can help treat diseases like glaucoma. However, the effects of cannabis aren’t long-lasting—it’s difficult to concentrate or even drive, making cannabis an unideal treatment option. 

Research is ongoing into the effect cannabis has on your vision and eye health. Researchers are looking into the possible harm cannabis can have on peripheral vision and visual processing. Currently, there is no definite proof that cannabis can harm your eyes. 

If you know you’ve recently had cannabis with THC in any form, that’s the likely cause of your red eyes. In general, eye redness has many potential causes. 

Consume Cannabis Responsibly 

While there isn’t any confirmed risk for your eye health associated with cannabis, remember to consume this substance safely. Cannabis can affect your decision-making and ability to drive.

The best way to prevent damage from cannabis is to not use it. If you do use cannabis, here are some tips to keep in mind: 

• Avoid frequent use of cannabis
• Never use cannabis and drive or operate machinery
• Avoid mixing cannabis with other substances like alcohol
• Consume cannabis in a safe, familiar place

Why Else Might Your Eyes Be Red? 

While cannabis can make your eyes red, there are many other possibilities. Red eyes can have many causes, some serious and others not. In general, recurring red eyes mean you should visit your eye doctor. 

Possible causes of red eyes include pink eye, dry eyes, injury, or blepharitis. 

Pink Eye

Pink eye, also known as conjunctivitis, occurs when bacteria, allergens, or a virus causes inflammation in the conjunctiva, the membrane lining your eyelid and eyeball. When this happens, your eye becomes swollen, red, and uncomfortable. This condition can be extremely contagious, depending on the type of pink eye. 

The types of pink eye include: 

• Bacterial pink eye: caused by bacteria entering the eye
• Viral pink eye: caused by a virus like the common cold
• Allergic conjunctivitis: caused by allergens entering the eye

Dry Eyes

Dry eyes occur when your tears can’t hydrate your eyes effectively. This condition happens due to issues in the tear film. The tear film’s layers (mucus, water, and oil) work together to keep your eyes moist and clean, but problems can arise, leading to fewer tears or poor-quality tears.

Dry eyes can cause redness, irritation, blurry vision, or a burning sensation. 

Injury

An eye injury can lead to redness caused by irritation or bleeding. You may get hit in the eye, exposed to an irritant, or experience a foreign object in the eye. 

Blepharitis 

Blepharitis is the inflammation of the eyelids, typically caused by the meibomian glands surrounding the eyelids becoming clogged or blocked. It’s a chronic condition that can lead to dry, red, irritated eyes. 

Red Eyes? Visit Your Eye Doctor

Red eyes are a common reaction to ingesting cannabis, but they can mean many potential eye problems. Make sure you visit your eye doctor if eye redness won’t go away, reoccurs, or your red eyes happen alongside other symptoms. 

Contact Willoughby Doctors of Optometry if you’re experiencing red eyes.