Dilated Pupils Drugs, Signs of Drug Use in the Eyes

Changes in the eye associated with intoxication may lead to attempts to cover up the problem. However, changes in pupil size, eye movements, and hallucinations are nearly impossible to hide, and they are reliable symptoms of intoxication on many drugs of abuse. Read more about the different treatment options for you or your loved ones struggling with drug abuse.

Dilated Pupils Drugs. What Drugs Cause Dilated Pupils?

The round opening in the center of the iris (the colored tissue that makes the “eye color” at the front of the eye). The pupils naturally dilate depending on your exposure to light. When the light is too bright, your pupils will constrict to minimize the amount getting into your eyes and dilate (widen) in dim light. The dilation of the pupil is an involuntary nervous system response to light that protects your eyes from too much light and aids your vision when in poorly lit areas. However, light is not the only factor that can affect pupil dilation. Distance, medications, color, drug use, and underlying health factors like sexual attraction and arousal can also play a role.

Dilated pupils, an enlargement of the black portion of the center of the eye, are one common symptom of drug use. Some drugs trigger the body’s fight-or-flight adrenaline response by interacting with serotonin and adrenergic receptors in the brain. This chemical reaction leads to mydriasis, the muscle relaxation that expands the eye’s pupil and lets in more light.

Stimulants and psychotropic drugs most commonly cause pupil dilation. However, this symptom can result from ingesting alcohol, mescaline, cocaine, ecstasy, LSD, psilocybin (magic mushrooms), MDMA (Molly/Ecstasy), amphetamines, cannabis, inhalants, narcotics, hallucinogens, bath salts, ketamine, and SSRI antidepressants. Pupil dilation is also associated with heroin and opioid withdrawal. This symptom tends to wear off, along with the other effects of the drug. Some drugs, most commonly opioids such as heroin, cause pinpoint pupils. The pupils get smaller and do not respond to light.

Signs of Drug Abuse in the Eyes. Redness and Drugs Dilated Pupils

What are the drugs that dilate pupils? The eyes still seem to offer clear clues to a person’s sobriety or lack thereof. How much does the size of your pupils actually have to do with the substances you’ve taken? People’s pupils on illicit drugs may be different depending on each particular substance. Almost every drug of abuse can cause eye changes on eyes on drugs. Below are the specific changes in eye motion, pupils, or vision that can indicate intoxication or overdose from specific substances.


  • Intoxication can cause double vision or blurry vision.


  • Ecstasy, Molly, MDMA, and similar drugs can cause blurred vision and changes in pupil size. The drugs can also cause rapid quivering of the pupils (nystagmus).


  • Recreational doses can cause altered blurry or double vision. Remember that dilated pupils are a sign of overdose. 

Crack Cocaine and Cocaine

  • As the drug stimulates the brain and releases endorphins and adrenaline, the body will react by dilating the pupils. Symptoms of overdose include hallucinations, including visual hallucinations.


  • A common cough-suppressing ingredient in cold and flu medicines, this substance can cause intoxication. A symptom of DXM abuse is rapid, involuntary eye movements called nystagmus.


  • A depressant sometimes called liquid ecstasy, GHB can be abused by putting the drug in the eyes using eye drops. It is, however, more commonly mixed into a drink and consumed orally. The drug also causes hallucinations.


  • Mescaline, LSD, and other pupils dilated drugs; similar drugs cause the pupils to dilate. The user experiences hallucinations, which may be visual.


  • This narcotic can cause drooping eyelids due to sleepiness. The drug will also cause the pupils to constrict, leading to pinpoint pupils.


  • Abusing substances like paint thinner or nitrous in canisters can lead to watering and red eyes as a sign of intoxication.


  • Rapid, involuntary eye movement and dilated pupils are symptoms of intoxication from this narcotic-like drug. Ketamine can also cause visual impairment, like alcohol.


  • One of the symptoms of methamphetamine intoxication is rapid eye movements – movements that are usually about 10 times faster than average eye movement.


  • Both legal and illicit narcotic drugs – including heroin, hydrocodone, morphine, and fentanyl – constrict the pupils. At high doses, one of the symptoms of overdose is pinpoint pupils that do not respond to changes in light.

PCP (phencyclidine)

  • Rapid eye movements that are involuntary. A person intoxicated on PCP may also develop a blank stare, during which they do not respond to direct visual stimuli.


  • These can cause irreversible vision loss, potentially due to brain damage, but also due to maculopathy.

Get Help. Get Better. Get Your Life Back.

Searching for Accredited Drug & Alcohol Rehab Centers Near You? Or Mental Health Support?

Even if you have failed previously, relapsed, or are in a difficult crisis, we stand ready to support you. Our trusted behavioral health specialists will not give up on you. Call us when you feel ready or want someone to speak to about therapy alternatives to change your life. Even if we cannot assist you, we will lead you wherever you can get support. There is no obligation. Call our hotline today.

FREE Addiction Hotline – Call 24/7

Pupil Size Statistics

Substance abuse continues to be a significant problem in our society, with millions of adolescents and adults using illicit drugs. Numerous illicit drugs or chemicals are causing unwanted physiological changes in our bodies. Several of these may have ophthalmic effects. A change in pupil size can be an indication of drug consumption. In the dim light, your pupil expands to allow more light to enter your eye. In bright light, it contracts. Understanding their adverse effects on the eye can aid in early diagnosis and initiating appropriate treatment.

2 to 4 mm

The normal pupil size in adults varies from 2 to 4 mm in diameter in bright light

Source: NCBI

4 to 8 mm

4 to 8 mm is the normal pupil size in adults in dim light.

Source: NCBI

3 to 6.5 mm

(3.0 to 6.5 mm) pupil size standards are used by police officers for detecting drug impairment.

Source: NCBI

Drugs Fact Sheet – Effects on the Eyes

Drugs Dilated Pupils Caused by Alcohol

Alcohol intake in short term leads to dilated pupils, slower pupillary reaction, diplopia, night vision disturbances, decreased contrast sensitivity, congested eyes, twitching of eyelid (myokymia) due to excessive intake and nystagmus. Alcohol intake may impair the vision or orientation to visuospatial stimuli due to the various mechanisms. Chronic intake of alcohol can cause external ophthalmoplegia (due to thiamine deficiency), toxic amblyopia, and age-related macular degeneration (ARMD).

Drugs Dilated Pupils Caused by Methanol

Methanol intake in the form of an adulterated drink can lead to metabolic acidosis (due to toxic metabolite formic acid). Symptoms include headache, dizziness, nausea, vomiting, abdominal pain and blurred vision. The onset of symptoms is usually delayed for 12-24 h. In severe poisoning, dyspnoea, coma, convulsion, and blindness may occur. Fatal dose can be as little as 30 ml and blindness can occur with as little as 10 ml. 

Drugs Dilated Pupils Caused by Cannabinoids

The active compound is tetrahydrocannabinol (THC), and route of intake can be smoking or oral ingestion. The effects of smoked cannabinoid begin within minutes and usually last for 1-3 hours. Cannabis intake leads to conjunctival injection, dilated pupils, reduced accommodation amplitude and impaired oculomotor function in chronic users. Impaired oculomotor function can manifest in the form of increase in latency to initiate saccades, impairment in processing of saccades and impaired visuospatial working memory, and smooth pursuit eye tracking performance.

Drugs Dilated Pupils Caused by Opiates

Opiates include numerous substances such as morphine (naturally occurring), heroin (semisynthetic), meperidine, and methadone (synthetic derivatives) and prescription opioids, including hydrocodone, oxycodone, pentazocine, and fentanyl. Both legal and illicit opiate drugs constrict the pupils. At high doses, one of the symptoms of overdose is pinpoint pupils that do not respond to changes in light.

These drugs act through the opioid receptors and cause a decrease in the pupillary size and in the velocity of constriction to light stimulus and dilatation after the light stimulus is removed. The effect usually starts in 15-60 min and lasts for 3-5 hours. The effect on pupil diameter in dependent and non-dependent individuals varies because of the development of tolerance. 

A study on the effect of heroin has found that pupillary constriction starts in 15 min and persists for at least two hours in non-dependent individuals, whereas dependent individuals show recovery from pupillary constriction after 15 min.

Drugs Dilated Pupils Caused by Cocaine

Cocaine can be ingested orally, and combined opioid and cocaine abusers use it as an intravenous injection. It is often used with alcohol. With freebase inhalation, effects occur within 4-6 sec and last for 5-7 min only. When the powder is sniffed, effects are produced within 1-3 min and last for about 30 min.

Cocaine causes dilated pupils because of inhibition of reuptake of norepinephrine. High concentrations may cause cycloplegia, and in chronic users, exophthalmos and retraction of the upper eyelid can occur. A case of severe sinusitis following intranasal cocaine abuse was reported, spreading to the orbit and leading to optic neuropathy and orbital apex syndrome.

Cocaine users can also present with complications like superficial punctate keratitis, epithelial defects, and ulcers because of contamination through eye rubbing or retrograde passage of the substance through the nasolacrimal duct by sniffing, as well as direct toxic effects from substance smoke.

Drugs Dilated Pupils Caused by Methamphetamine 

Meth increases dopamine production in the brain and activates reward centers, giving a sense of euphoria soon after taking the drug and causing aggressiveness, anxiety, and dilated pupils. It is known to cause crystalline retinopathy by intranasal methamphetamine use. Retinal vascular occlusive disease can also occur with methamphetamine use. Psychostimulants act on dopamine receptors in the brain. These enhance the activity of sympathetic nervous system leading to increased pulse rate, respiratory rate and blood pressure.

Drugs Dilated Pupils Caused by Prescription Stimulants

Prescription stimulants include amphetamines, methylphenidate for attention-deficit hyperactivity disorder, and nasal decongestants such as pseudoephedrine, phenylephrine, promethazine, phenylpropanolamine, and oxymetazoline. These drugs can also be abused and drug effects on the eye can occur in the form of pupil dilatation and precipitation of angle-closure glaucoma in predisposed individuals with narrow angles.

Anecdotal case of anisocoria in a patient on oral decongestant pseudoephedrine for sinusitis in which anisocoria occurred because of the absence of pupil dilatation in one eye with latent form of Horner’s syndrome has been described. Promethazine because of anticholinergic property and phenylpropanolamine due to sympathomimetic activity have been reported to cause acute angle-closure glaucoma.

Why Do Drugs Dilate Pupils?

The pupils are the black dots in the center of your eyes that change in size in order to regulate the amount of light that enters. This light regulation is crucial to things like normal vision and focus. The size of your pupil is directed by the colored portion of your eye called the iris. Although pupils are generally responsive to your needs for better vision, they sometimes change size as an emotional response or due to chemical changes in the body.

Chemical changes in your body that affect your pupils can include medications and illicit drugs like heroin, methamphetamine, cocaine and marijuana. Dilation due to substance use or taking such medications is usually a temporary reaction to the substance. Poisoning can also cause dilation of your pupils, as can brain injury and disease.

While these other, non-drug related issues can cause dilated pupils, it is one of the most common signs of drug abuse. Knowing what drugs cause dilated pupils can be beneficial in identifying that someone has a substance use problem and may help determine what kind of drugs they are abusing.

What drugs cause dilated pupils? Nearly every substance of abuse can cause changes in the eyes.
What drugs cause dilated pupils? Nearly every substance of abuse can cause changes in the eyes.
Ryan Zofay forming a circle and hugging friends.

Get Your Life Back

Find Hope & Recovery. Get Safe Comfortable Detox, Addiction Rehab & Mental Health Dual Diagnosis High-Quality Care at the We Level Up Treatment Centers Network.

Hotline (877) 378-4154

Can Alcohol Dilate Your Pupils?

Alcohol causes every muscle in the body to relax, including the iris muscles, which make the pupils dilate and constrict. As a result, a person intoxicated with alcohol will experience slower-than-usual pupil dilation and constriction.

Slow pupil reaction related to alcohol use is why people are often advised against drunk driving. It affects an intoxicated person’s response to oncoming headlights, which can be dangerous. The pupil dilation due to alcohol intake is only temporary, which means that alcohol will only affect the pupils when someone is intoxicated.

How Long Do Dilated Pupils Last After Drugs?

The ability to reverse pupil dilation depends on the cause. When taking an eye exam, your doctor will put dilation drops into your eye to keep the pupil dilated, allowing them to view your eye effectively.  After the eye exam, the effects of the dilating eye drops will take some time to wear off. The time they take to wear off depends on the person.

Usually, after your eye doctor puts on some dilation drops on your eyes, it may take 20 to 30 minutes before your pupils are fully dilated. After they are dilated, it might take 4 to 6 hours before the effects wear off. Some people, especially those with lighter-colored eyes, might take longer than usual for the effects to wear off.

For pupil dilation caused by medications (dilated pupils drugs), whether prescription or over-the-counter, the condition might persist until the effects of the drug wear off. It can be impossible to tell precisely how long the dilation effects will last since people react differently to various medications.

First-class Facilities & Amenities

World-class High-Quality Addiction & Mental Health Rehabilitation Treatment

Rehab Centers Tour

Renowned Addiction Centers. Serene Private Facilities. Inpatient rehab programs vary.

Addiction Helpline (877) 378-4154

Proven recovery success experience, backed by a Team w/ History of:


Years of Unified Experience


5-Star Reviews Across Our Centers


Recovery Success Stories Across Our Network

  • Low Patient to Therapist Ratio
  • Onsite Medical Detox Center
  • Comprehensive Dual-Diagnosis Treatment
  • Complimentary Family & Alumni Programs
  • Coaching, Recovery & Personal Development Events

What Drug Causes Dilated Pupils (Pupil Dilation Drugs Chart)?

What are the drugs that cause dilated pupils? There are various types of pupils dilated drugs, legal and illegal that cause pupils to dilate due to their effect on the brain’s neurotransmitters. Some pupil dilator drugs include:

  • Ecstasy
  • LSD
  • Cocaine
  • Crack Cocaine
  • MDMA
  • Crystal Meth
  • Ketamine
  • Mescaline

People may also become addicted to prescribed or over the counter (OTC) medication. Some of which are:

  • Antihistamines
  • Antidepressants
  • Benzodiazepines
  • Stimulants
  • Bath salts
What drugs cause pupil dilation? After taking cocaine, marijuana, or amphetamines, for example, your pupils get noticeably larger (Mydriasis), while opiates such as heroin constrict the pupils (Miosis).
What drugs cause pupil dilation? After taking cocaine, marijuana, or amphetamines, for example, your pupils get noticeably larger (Mydriasis), while opiates such as heroin constrict the pupils (Miosis).

World-class, Accredited, 5-Star Reviewed, Effective Addiction & Mental Health Programs. Complete Behavioral Health Inpatient Rehab, Detox plus Co-occuring Disorders Therapy.

CALL (877) 378-4154

End the Addiction Pain. End the Emotional Rollercoaster. Get Your Life Back. Start Drug, Alcohol & Dual Diagnosis Mental Health Treatment Now. Get Free No-obligation Guidance by Substance Abuse Specialists Who Understand Addiction & Mental Health Recovery & Know How to Help.

What are the Short-Term Side Effects of Pupil Dilation Drugs?

Whether you have dilated pupils because of an eye exam or drug dilated pupils, you will experience some short-term side effects. For example, you might experience some form of discomfort when you come close to bright lights. This is because dilated pupils are sensitive to bright beams. 

The discomfort you experience is caused by your eyes trying to adjust to the lighting conditions through constriction. In this case, your pupils will be too sensitive to the light but cannot contract normally.

Other possible short-term side effects of dilated pupils drugs include:

  • Blurry vision
  • Migraines
  • Trouble focusing on close objects
  • Eye pain

What is the Long-Term Damage & Eye Diseases from Drug Abuse?

When an individual struggles with drug addiction and substance abuse for a long time, they are more likely to suffer severe health problems. Diabetes, blood pressure problems, heart damage, kidney and liver damage, cancer, and ulcers in the stomach and small intestine are just a few of the frequently reported health issues of drug abuse.

Drug abuse is also correlated to long-term issues with vision due to damage to the eyes, ocular nerve, and the brain. Here are a few long-term problems to the eyes caused by substance addiction and abuse:

  • Age-related macular degenerationThis cause of vision loss can occur in people over age 50 regardless of long-term health; however, it is more likely to happen and can be worsened, due to substance abuse, especially abuse of alcohol and tobacco.
  • EndophthalmitisThis is inflammation inside the eyes caused by infection. This condition is sometimes associated with injecting drugs using dirty needles, which can cause infections to spread all over the body.
  • Damage to corneasKeratitis is inflammation of the corneas, which can distort vision, and topical anesthetics, cocaine, and crack cocaine can all cause this type of inflammation. Long-term abuse causing consistent keratitis can lead to infectious ulcers in the corneas and corneal perforation.
  • Dry eye syndromePersistent dry eyes, problems forming tears, and feeling as though eyes are irritated are issues that can develop due to heavy alcohol consumption, although they are not related to current alcohol intoxication.
  • GlaucomaChanges in blood pressure alter the fluid pressure in the eye itself, and long-term increases in intraocular pressure can lead to glaucoma. Alcohol use disorder is a common factor in substance-induced glaucoma.
  • Hallucinogen persisting perception disorder (HPPD): More often called flashbacks, this condition involves sudden, repeated recurrences of some of the sensory changes experienced during LSD use. This can include seeing things that are not there and distortions in the peripheral vision. HPPD is most common with LSD and not associated with organic hallucinogens like psilocybin.
  • LesionsDrugs that come as eye drops can cause damage to the conjunctiva or the whites of the eyes. Long-term damage includes noncancerous lesions.
  • Ocular bone damageSnorting drugs can damage the tissues around the sinuses to the point of degeneration; most often, this appears as septal perforation or extreme damage of the tissue between nostrils. However, tissue damage can continue into the upper palate and the small bones around the sinuses, including the ocular ridge bones.
  • Maculopathy: This is degeneration of the retina, typically related to age but also caused by substance abuse in some cases. The central part of the person’s vision becomes blurry and distorted. This condition often rapidly worsens because the eye and brain will compensate for this vision loss in the early stages. Poppers, cocaine, and other drugs that are snorted are associated with maculopathy.
  •  Persistent changes in eye movementNystagmus, or rapid eye motion, is a symptom of intoxication on a variety of drugs. If changes in eye movements do not go away after the person has detoxed from the substance, it could indicate brain damage that has changed how the brain processes visual stimuli.
  •  Toxic cataractsLong-term substance abuse can lead to the development of cataracts due to the poisonous effects of the substance on the body.
What drug causes dilated pupils? The pupils can also widen for if you're an epileptic who's on medication. So we like to look for other, conclusive signs. For example, if someone is heavily sweating.
What drug causes dilated pupils? The pupils can also widen for if you’re an epileptic who’s on medication. So, we like to look for other, conclusive signs. For example, if someone is heavily sweating.
  • Retinal vascular occlusive disease (RVOD): This condition is caused by changes in blood pressure, or a blood clot, which prevents healthy blood flow to and from the eye. Swelling, bleeding, and abnormal blood vessel growth in the retina can eventually cause partial or total vision loss. RVOD is related to high blood pressure, cholesterol, diabetes, glaucoma, inflammatory conditions, and blood clotting, all of which may develop due to past substance abuse. Additionally, smoking is a direct cause of RVOD.
  •  Talc retinopathyThis buildup of white or yellowish crystalline particles in the vascular areas of the eye has been associated with some intravenous and intranasal drug abuse.
  •  Yellowed eyes: Intoxicating substances like alcohol, opioids, steroids, and stimulants can damage the liver, leading to cirrhosis, which can cause jaundice (yellowing of the skin and the whites of the eyes). Hepatitis C, which can be contracted by sharing needles during drug use, can also cause liver failure and jaundice.
  •  Wernicke’s encephalopathy: This condition is sometimes caused by excessive, long-term alcohol consumption. It has been associated with disc edema, causing optic neuropathy or nerve death in the cluster connecting the eye to the brain.

Experience Transformative Recovery at the We Level Up Treatment Center.

See our authentic success stories. Get inspired. Get the help you deserve.

We Level Up Treatment Centers for Drug Alcohol Rehab Detox Behavioral Mental Health Dual Diagnosis Therapy
We Level Up Treatment Centers for Drug Alcohol Rehab Detox Behavioral Mental Health Dual Diagnosis Therapy
We Level Up Treatment Centers for Drug Alcohol Rehab Detox Behavioral Mental Health Dual Diagnosis Therapy
Voluntarily testimonials from the We Level Up Treatment Center network vary. Not intended as a guaranteed treatment or outcome as each person's journey is unique.

Start a New Life

Begin with a free call to an addiction & behavioral health treatment advisor. Learn more about our dual-diagnosis programs. The We Level Up treatment center network delivers various recovery programs at each treatment facility. Call to learn more.

  • Personalized Care
  • Caring Accountable Staff
  • World-class Amenities
  • Licensed & Accredited
  • Renowned w/ 5-Star Reviews

We’ll Call You

Treatment for Drug Abuse 

To determine the most effective ways to treat drug abuse and co-occurring alcohol addiction, it’s crucial to assess all the symptoms accurately. When a mental health professional has evaluated the symptoms, it may be determined that another form of depression is present and needs a particular treatment. Very often, some combination of medication, psychotherapy, and lifestyle changes are effective for coping with functional.

Medically Assisted Detox

Detox is often considered the first stage of treatment. It will help you navigate the complicated process of alcohol withdrawal but doesn’t address patterns of thought and behavior that contribute to alcohol use. Various treatment approaches and settings can help provide the ongoing support necessary to maintain long-term sobriety after you complete detox.

Cravings are very common side effects of drug dependency during detox and can be challenging to overcome. This often leads to relapse. Constant medical care provided during inpatient treatment helps prevent relapse. Clinicians can give the necessary medication and medical expertise to lessen cravings and the effects of alcohol withdrawals.

Psychotherapy for Depression

Several different modalities of psychotherapy have been used in the treatment of depression, including:

  • Cognitive Behavioral Therapy (CBT) – is an effective treatment that involves changing both the patterns of negative thoughts and the behavioral routines which are affecting the daily life of the depressed person for various forms of depression.
  • Person–centered therapy is a strategy that allows and encourages clients to understand and resolve their concerns in a safe, supportive environment.
  • Solution Focused Therapy – an approach interested in solutions that can be quickly implemented with a simple first step leading to further positive consequences.

Dual Diagnosis Treatment

Alcoholism and mental health disorders often co-occur. In many cases, traumatic experiences can result in a mental health disorders and substance abuse. Dual diagnosis rehabilitation treats both of these issues together. The best approach for the treatment of dual diagnosis is an integrated system. This strategy treats both the substance abuse problem and the mental disorder simultaneously. Regardless of which diagnosis (mental health or substance abuse problem) came first, long-term recovery will depend largely on the treatment for both disorders done by the same team or provider.

Medication-Assisted Treatments

Medication-Assisted Treatments (MAT) for alcohol use and mental health disorders are commonly used in conjunction with one another. This includes the use of medications and other medical procedures. During your rehab, the staff from your treatment facility will help you identify what caused your addiction and teach you skills that will help you change your behavior patterns and challenge the negative thoughts that led to your addiction. Sometimes, the pressures and problems in your life lead you to rely on substances to help you forget about them momentarily.

Contact one of our helpful treatment specialists today if you or a loved one are struggling with long-term substance abuse, side effects, and other co-occurring mental health conditions such as depression. We Level Up NJ can provide information on dual diagnosis and detox programs.

What drugs make pupils dilate? If you suspect a friend or loved one’s dilated pupils are a sign of substance use disorder, consider discussing your concerns with a substance use counselor or other healthcare professional.
What drugs make pupils dilate? If you suspect a friend or loved one’s dilated pupils are a sign of substance, use disorder, consider discussing your concerns with a substance use counselor or other healthcare professional.

Search We Level Up NJ “Dilated Pupils Drugs” Topics & Resources