Substance Use

High Eyes: How Pupil Size Can Show Someone Is High on Weed

woman with large pupils

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Can Pupil Size Show if Someone Is High on Weed?

Smoking weed can cause a range of side effects. Sometimes, someone’s drug use can be evident to others when they display particular signs. Changes to pupil size (particularly dilated pupils) are just one way to tell if someone is using marijuana. Keep reading to learn more about how pupil size and other side effects like confusion and coordination problems can show someone is high on weed. 

If you think your marijuana use is problematic or you are worried about a loved one, reach out to us at Zinnia Health at (855) 430-9439. You can also send a message to learn about the substance use disorder treatment options we offer.

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What Causes Changes to Pupil Size?

The following side effects may cause changes to your pupil size.

1. Blood Vessel Dilation 

Smoking weed can cause pupils to appear larger than usual. It can also cause bloodshot eyes. This is where the whites of the eye (sclera) appear red or have visible blood vessels running through them. Red eyes and larger pupil size are linked to the dilation of blood vessels caused by smoking cannabis

2. Blood Flow

The eyeballs are affected in several ways because of the way cannabinoids bind to receptors in the brain linked to blood flow and blood pressure.

Smoking weed increases blood flow to the eye, which causes red eyes. Dilation of the pupils occurs for the same reason. The way marijuana affects neurotransmitters can lead to a range of changes in the retina and ocular tissues. For most people, this appears as red eyes and dilation of the pupils. 

Are Pupil Changes Only Linked to Weed?

Drug use involving other substances can have the opposite effect, with people displaying pinpoint pupils (constriction). However, if you want to tell whether someone is high on weed, red eyes, and pupil dilation are the fundamental eye changes to note. 

Can You Treat High Eyes?

Some people may use eye drops to help with eye changes relating to marijuana. Although eye drops are unlikely to treat pupil size changes, they may help alleviate bloodshot eyes. Eye drops constrict the blood vessels in the cornea and conjunctival capillaries, which allows the whites of the eyes to return to their usual color.

Some people may experience eye changes after only a small amount of marijuana, while others will need to smoke more to see the effect.

Can Pupil Size, Constriction, and Dilation Relate to Other Drug Use?

Changed pupil size is a key indicator of drug abuse relating to a range of substances. While marijuana is known for causing bloodshot eyes and pupil dilation, other drugs can have the opposite effect.

Stimulants, hallucinogens, narcotic drugs, opioids, benzodiazepines, and prescription drugs can all affect pupil size. Some substances can cause both dilation and constriction. 

Drugs linked to pupil dilation:

Drugs linked to pupil constriction:

  • MDMA (Molly)
  • Cocaine
  • Oxycodone
  • Fentanyl 

Other Ways To Tell if Someone Is High on Weed

If you think someone may be high on marijuana, look out for the following signs:

  • Delayed reactions
  • Appearing very relaxed
  • Eating more than usual
  • Forgetfulness
  • Inability to concentrate in conversations

Physiological Effects of Weed

Marijuana use can cause several physiological effects, including red eyes and pupil dilation. Someone smoking marijuana may experience the following:

  • Visual impairment 
  • Low blood pressure
  • Difficulty balancing or focusing 
  • Slow movement 
  • Dry mouth

Psychological Effects of Weed

Because of how THC interacts with neurotransmitters in the brain, smoking marijuana can lead to psychological effects and mental health problems, including:

  • Hallucinations
  • Confusion
  • Memory loss
  • Psychosis 
  • Anxiety
  • Paranoia
  • Depression

People with marijuana use disorders may benefit from addiction treatment that also focuses on mental health. 

Marijuana use disorder can lead to physical and mental health problems. If you smoke marijuana often and believe it’s impacting your life quality, get in touch. Our treatment programs can help you break free of addiction. Call (855) 430-9439 or send a message to talk to us today.

Can Marijuana Use Cause Long-Term Damage?

If you smoke marijuana regularly, it is natural to have health concerns about its use. This is particularly true when it comes to eye health and long-term damage. Some studies show that marijuana use may benefit glaucoma treatment. Others indicate that long-term damage to the eyes from persistent marijuana use is possible. 

Regular marijuana use is linked to long-term damage, such as irreversible visual impairment with photopic vision loss.

Eye damage isn’t the only concern for people who smoke marijuana. Long-term use can contribute to the following:

Substance use disorder can be the most significant health concern of all. Someone with a substance use disorder may experience all of the medical issues discussed above, in addition to many other physical and behavioral issues. 

Signs of Marijuana Use Disorder

If you have concerns about the amount of marijuana you smoke, you may have a marijuana use disorder. This type of substance use disorder can affect most areas of your life. If you identify with any of the following signs, you may require specialist substance use disorder treatment

  • Thinking about marijuana a lot of the time
  • Spending lots of your time smoking marijuana or recovering from its use
  • Giving up hobbies that you once enjoyed
  • Avoiding social situations unless marijuana use is involved
  • Craving the effects of marijuana
  • Feeling withdrawal symptoms, such as anxiety or anger, when you do not have marijuana
  • Spending a lot of time sourcing marijuana

Getting Help for Marijuana Addiction

Marijuana addiction (like any other substance use disorder) is a progressive illness. Without professional help, it can be difficult to break free from the grip marijuana has over your life.

If you believe you have a marijuana addiction, remember many people have been in your position and have successfully recovered with the proper treatment. We know how hard it can be to make the decision to break free from addiction, but we’re here for you.

At Zinnia Health, our teams of addiction professionals take an all-encompassing treatment approach to tackle substance use disorder for good. Our treatment centers offer addiction treatment programs designed to leave no stone unturned.

We focus on detox, mental health, and behavioral therapies. By focusing on all aspects of addiction, we can truly understand your substance use disorder and provide a comprehensive treatment model.

Let us help you recover from substance use disorder and related mental health concerns. Our team is standing by. Email us today or call (855) 430-9439 to discuss the help we have available and learn about our addiction treatment options. Wherever you are in your recovery journey, we can provide the support you need.

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(855) 430-9439
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