Categories
BLOG

eyes effected by weed

Why does weed make your eyes red?

Copy article link to clipboard.

Link copied to clipboard.

Contents

  1. Under pressure: lower blood pressure and dilated capillaries
  2. Do edibles make your eyes red?
  3. The redder the better?

Among the most common effects of marijuana use (and telltale signs you’ve recently partaken) is red, bloodshot eyes. It’s to be expected, sure, but that doesn’t answer the mysterious question pondered by generations of stoners: why does weed make your eyes red?

For weed novices, the onset of bloodshot eyes could cause a panic-induced internet search asking “ can smoking weed damage your eyes? ” Thankfully, as those who regularly consume cannabis can tell new users, there are no serious health risks associated with your sudden red-eyed circumstance. You’re probably not experiencing an allergic reaction or some bigger complication. Some might poke fun or chastise you for sporting your so-called “ weed eyes ” in public, but otherwise, it’s a completely natural occurrence that transpires after smoking cannabis.

In fact, your eyes turning red has nothing to do with the act of smoking at all.

Under pressure: lower blood pressure and dilated capillaries

After consuming a cannabis-based product (flower, concentrate, edible, etc.), users generally experience an increase in heart rate and blood pressure. This effect is due to the plant’s cannabinoids, which are chemical compounds responsible for some of the therapeutic and medicinal benefits of cannabis, and their initial interaction with the body. This rise in blood pressure and heart rate is comparable to normal physical activities like exercise or sex.

It generally takes about five to ten minutes for users’ heart rates to return to normal and for blood pressure to begin to decrease. As the blood pressure lowers, the blood vessels and capillaries dilate, including the ocular capillaries . The dilation of ocular capillaries causes increased blood flow to the eyes, which results in your eyes turning red and also reduces intraocular pressure.

The dilation of ocular capillaries causes increased blood flow to the eyes, which results in your eyes turning red in the process, and also reduces intraocular pressure. Photo by: Gina Coleman/Weedmaps

Image lightbox

In fact, according to Dr. Melanie Bone, a board-certified OB-GYN who practices in West Palm Beach, Florida, “It’s cannabis’ ability to reduce intraocular pressure in the eyes that makes it a potentially viable treatment for glaucoma , a group of eye disorders that causes damage to the optic nerves which can eventually lead to blindness. It also happens to explain why your eyes become bloodshot after smoking cannabis.”

Evidence that the THC found in cannabis can lower intraocular pressure (IOP) is a major reason why many glaucoma patients have attempted to use medical marijuana to treat and relieve symptoms of the disease. It’s important to know that some studies have contradicted or added a caveat to the claim that cannabis is beneficial for glaucoma. For instance, a 2018 study conducted at Indiana University found that cannabidiol (CBD), the non-intoxicating cannabinoid found in marijuana, could potentially worsen the condition by increasing eye pressure . More research into the use of cannabis for glaucoma treatment is needed.

Do edibles make your eyes red?

Similar to smoking cannabis, ingesting edibles could also make your eyes turn red. Again, this depends on the amount of THC consumed. Remember, it’s not the smoke itself that makes your eyes red, but rather the ability that cannabinoids have to lower blood pressure, causing blood vessels and capillaries to dilate.

The redder the better?

The amount your blood pressure is lowered and how red your eyes become depends on the amount of THC you consume.

Tetrahydrocannabinol (THC), the most common cannabinoid in the plant, is responsible for the intoxication associated with smoking cannabis. The greater the concentration of THC in a cannabis product, the stronger the effects and the redder your eyes become.

The greater the concentration of THC in a cannabis product, the stronger the effects and the redder your eyes become.

Image lightbox

So, red eyes can act as a sign that your cannabis has a high cannabinoid content (i.e., it’s potent). In other words, if your eyes are noticeably bloodshot after consumption, there’s a good chance you’ve landed yourself some highly potent weed.

Other than being a dead giveaway that you’ve recently consumed cannabis, you have no reason to be concerned about the redness of your eyes. Cannabis-induced eye redness will typically only last a few hours and can easily resolve if you have the right tools at your disposal.

It isn’t a bad idea to have eye drops (or some sunglasses) on hand. Look for eye drop brands that are specifically designed to reduce eye redness. There are other methods that could potentially help combat cannabis-induced bloodshot eyes, including staying hydrated, washing your face and eyelids with cold water, or simply consuming cannabis products with lower THC levels.

Ever wonder why using marijuana or cannabis makes your eyes red or bloodshot? Discover why weed gives you bloodshot eyes.

Could Regular Pot Smoking Harm Vision?

Study suggests that it might slow signaling among cells that deliver visual information to the brain

HealthDay Reporter

THURSDAY, Dec. 8, 2016 (HealthDay News) — Smoking pot regularly may be linked to a limited degree of vision impairment, a new French study suggests.

The finding stems from very preliminary research involving just 52 participants, 28 of whom were regular marijuana users. That meant they used marijuana at least seven times a week.

The question posed in the study: Does marijuana affect the healthy functioning of retinal ganglion cells (RGCs), which are situated on the surface of the retina? These cells receive incoming visual information, and are considered the first link in the pathway that connects the retina to the part of the brain where eyesight is processed.

The answer: Regular pot users do appear to experience a slight delay in their RGC signaling. And that could indicate impaired vision, the study authors said.

Still, experts stressed that the findings remain preliminary and people shouldn’t be overly alarmed by the findings.

And, according to study author Dr. Vincent Laprevote, his team now have to “measure if this delay is permanent, or recedes with cannabis cessation.” Laprevote is a hospital practitioner at the Pole Hospitalo-Universitaire de Psychiatrie du Grand Nancy in Laxou, France.

His team noted that marijuana has long been known to have an impact on nervous system communications.

To explore the possibility that this might include vision function, the French scientists conducted neural signaling tests to compare RGC function between regular pot smokers and nonsmokers.

Those tests determined that regular pot users experienced a 10-millisecond delay in the speed with which their RGCs sent key signals to the brain via the optic nerve.

The findings were published online Dec. 8 in the journal JAMA Ophthalmology.

Although the result could signal the potential for vision trouble, the team noted that it did not necessarily prove that regular smokers do actually experience vision impairment. The association seen in the study also did not prove that pot use actually caused the delay in RGC signaling, the researchers said.

Laprevote also pointed out that most of the participants did not complain of any vision issues before the study began. He suggested, however, that smokers might be experiencing vision trouble without being consciously aware of it.

Continued

Dr. Christopher Lyons co-authored an editorial that accompanied the study. He said that “the evidence [in the study] for decreased retinal function is weak for several reasons.”

Lyons pointed to the extremely small pool of patients, as well as the lack of visual impairment symptoms prior to the study, and a lack of clarity on additional lifestyle factors that could have affected the results, such as diet and cigarette smoking history.

Lyons, who is a professor in the department of ophthalmology and visual sciences at the University of British Columbia in Vancouver, still described the research as “timely,” given the increasing trend towards legalization of marijuana in the United States, for both medical and recreational use.

Also, medical marijuana has been promoted as an alternative treatment for the vision-robbing condition glaucoma, because research has shown it can lower blood pressure in the optic nerve for short periods of time. However, the American Academy of Ophthalmology does not recommend medical marijuana for glaucoma patients.

Lyons suggested that “further, more robust studies are needed to test whether long-term use of cannabis has any effect on retinal or optic nerve function.”

But Paul Armentano, deputy director of NORML, the nonprofit marijuana advocacy organization, argued that “it remains unclear at this time whether or not these findings possess any real-world significance.”

Armentano said, “Given the reality that tens of millions of people consume cannabis regularly, and that people around the world have been consuming cannabis for generations, one would presume that any potential adverse effects on vision would have been previously documented. Or that they are, at worst, nominal to the overwhelming majority of those who consume the substance.”

Study suggests that it might slow signaling among cells that deliver visual information to the brain