Do edibles make your eyes red? Short answer… yes.
Red eyes are the classic giveaway that someone has been consuming cannabis. This common side effect makes you look like Towelie from South Park as your eyes droop, get watery, and become red.
Everyone’s been there, and no doubt we’ve all made sure to have a bottle of Clear Eyes handy during our smoke sessions.
However, do cannabis edibles make your eyes red? Join us as we explore why red eyes happen and if edibles cause them or not.
Why does weed make your eyes red?
Right after smoking, THC starts to make its way into the brain and central nervous system (CNS). Once it gets there, THC begins to work its magic by raising the heart rate.
Blood pressure begins to go up along with the heart rate, but only for 5 to 10 minutes or so. After that, blood pressure returns to normal and then gradually decreases.
As the blood pressure decreases, blood vessels and capillaries begin to dilate. That means the blood vessels and veins start to widen, including the ocular capillaries.
Ocular capillaries are the tiny veins in your eyes, and you usually can’t see them. However, once they widen, more blood begins to flow into them.
The increased blood flow makes them visible throughout the whites of the eyes, making them appear red.
So why do some people not get red eyes, or why don’t I get red eyes all the time? It’s because of the THC content as well as individual blood pressure levels.
Basically, the higher the THC content, the more likely you’re going to get red eyes. However, it’s not all about THC content because, ultimately, blood pressure has the most significant influence.
Remember, blood pressure needs to be low enough to dilate the veins in our eyes for them to get red. Therefore, someone with high blood pressure may need more THC than someone with low blood pressure.
On the flip side, someone with low blood pressure likely experiences red eyes all the time.
Blood pressure is influenced by age, height, gender, diet, lifestyle, and much more. That’s why not everyone has the same experience when it comes to red eyes. Not only that, but tolerance plays into this phenomenon as well. If you are less affected by THC, the rest of your body generally is as well.
Cannabis and glaucoma
What if we told you that red eyes were actually a symptom of something good? It turns out that when the ocular capillaries dilate, it also reduces intraocular pressure.
Intraocular pressure is the fluid pressure inside the eyes, and when it’s too high, it causes glaucoma. Glaucoma is one of the leading causes of blindness, and it affects 60 million people worldwide.
Luckily, cannabis can help treat glaucoma, and it’s one of the more common reasons for medical cannabis prescriptions. One study showed that consuming cannabis can reduce intraocular pressure by up to 30%.
Do edibles make your eyes red?
The short answer is yes—because when you eat an edible, you’re still consuming THC. However, THC’s route to your brain is different from smoking or vaping, changing how red your eyes get.
How long do edibles take to work? The body breakdown
Smoking or vaping cannabis leads to the rapid absorption of THC. First, the smoke or vapor goes into the lungs, and then into the bloodstream.
The THC gets carried along with the bloodstream until it reaches the brain. From the time you smoke/vape until you feel the effects can be a matter of minutes.
When you eat delicious edibles like Baked Bros THC gummies, the THC goes through a long journey to get to your brain that can take a bit longer than smoking.
First, the edible needs to make its way down to the stomach, where it gets digested. The process of digestion can be complicated.
Once the edible gets digested (unless you absorb it sublingually or rectally), it goes into the intestines, and the THC gets absorbed into the bloodstream. However, instead of going to the brain, the THC gets processed by the liver first.
The liver turns the THC into a metabolite called 11-hydroxy-THC which can travel quickly through the bloodstream. Studies have shown that 11-hydroxy-THC has a longer onset and may feel more potent than regular THC.
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.
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 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.
THC causes vasodilation of your blood cells (lowers your blood pressure, blood cells increase in size) which is why your eyes get red. It’s a chemical response and is not derivative of smoking.
Vasodilation has nothing to do with the size of the cells, but of the vessels. Muscles in blood vessels (arteries and veins) will relax, leading to widening of the vessel and thinning of walls. Because there is more blood pumping through, and the membrane surrounding it is thinner, it is easier to see the red blood. You can’t change the size of a blood cell, and even if you could, you wouldn’t want to, as those blood cells would be unable to move into capillaries, leading to death.