What Drugs Cause Dilated Pupils?

When an individual does drugs, others can often tell because they display several noticeable signs. These signs can be physical, like changes in weight, behavioral, such as isolating one's self or engaging in risky behavior, or psychological, like consistent depression or irritation.

One of the most common physical signs that a person may be abusing drugs is having dilated pupils. Along with alerting others that an individual may be struggling with substance abuse, dilated pupils can also help reveal what specific drug they are using. Learn what drugs make eyes dilate with Diamond House Detox.

What Causes Pupils to Dilate When on Drugs?

Your pupils, or the small black dots in the center of your eye, change sizes based on the amount of light entering your eyes. By regulating the light, your pupils help you focus and maintain better vision in a range of lighting conditions. Factors such as your iris — the colored part of your eye — and emotions can influence the size of your pupils, with the muscles of the iris controlling dilation. Pupil dilation is most commonly caused by chemical changes.

Chemical changes can include medications as well as illicit drugs. When these drugs are taken, they can affect either the parasympathetic or sympathetic nervous system. Most drugs that cause pupil dilation are anticholinergic. That means they block neurotransmitters, mostly affecting the parasympathetic nervous system. These changes are generally much more drastic and appear despite changes in light compared to natural dilation changes, which is why pupil dilation and constriction are among the go-to symptoms people look for when they suspect someone is using drugs.

Your Pupil Size on Drugs

Dilated pupils are one way that eyes can react to drugs or chemicals in the body. Certain drug use can also present as:

  • Pupil constriction: Pupil constriction or myosis is another symptom of many people who use drugs. Typically, their drug of choice is heroin or opioids like morphine, codeine or methadone. When discussing opioid use, you'll often hear the phrase “pinpoint pupils” in relation to the phenomena. Individuals who have overdosed on the drug tend to have pinpoint pupils.
  • Uneven pupil dilation: Unequal pupils or anisocoria is the most uncommon presentation of medication-based eye changes, but it can happen as a result of medications that both constrict and dilate pupils. It can also indicate a serious issue like brain trauma, seizures, nerve damage or multiple sclerosis, among other things. Sudden or uneven dilation is abnormal, and you should contact a medical professional immediately.

When someone's eyes stop reacting to light as they should normally, it can be a sign there is something going on, whether that's drug use or another medical condition. If you notice someone you love has pupils that are smaller or larger than normal, or pupils that are uneven, it may be time to talk to them and see if they are using drugs that cause pupils to dilate. 

10 Drugs That Dilate Pupils

So, what drugs are most likely to make your pupils look big?

Several different types of drugs — anticholinergics and mydriatics, whether illegal or legal — can dilate pupils and indicate to friends, family members and authorities that an individual may be under the influence or misusing a specific substance. 

While various drugs, especially psychotropic stimulants, can cause the pupils to dilate, 10 of the most common drugs that can trigger this include:

  1. Antihistamines.
  2. Benzodiazepine.
  3. Cocaine.
  4. Ketamine.
  5. LSD.
  6. Marijuana.
  7. Methamphetamine/amphetamines.
  8. MDMA (Ecstacy).
  9. Selective serotonin reuptake inhibitor (SSRI) antidepressants.
  10. Stimulant medications, like for attention-deficit/hyperactivity disorder (ADHD).

Note that the abnormal dilation of pupils is not necessarily an indicator that someone is misusing drugs, particularly if they are on legal prescriptions. However, if you are close enough with someone to discuss their personal medical history and you notice their dilated pupils coincide with other symptoms of drugs, consider opening a dialogue with them and showing them you're here to support them in any way you can.

Other Symptoms of Drug Use

Some common indicators of drug usage include:

  • Insomnia.
  • Isolation from friends and family.
  • Runny nose.
  • Shaking.
  • Lack of motivation or disinterest in activities once enjoyed.
  • Mood swings.
  • Slurred speech.
  • Paranoia, with or without hallucinations.
  • Weight loss or weight gain.

If you notice these signs at the same time someone has abnormal pupil size, it could be an indication they may be using drugs or taking medication in a way that's inconsistent with prescription use.

Frequently Asked Questions About Drug Use and Dilated Pupils

At Diamond House Detox, we've worked with many concerned individuals who think someone they know is using drugs that cause eyes to dilate, along with other symptoms. Take a look at some of the most common questions we answer and see if they can help you better understand where to go from here.

What Other Medications Cause Dilated Pupils?

While the 10 drugs listed above account for many reported changes in pupil dilation, there are a number of other medications that can make the eyes dilate. If someone suddenly starts exhibiting dilated pupils, find out if they've recently started taking one of these medications before considering illicit drug use:

  • Decongestants
  • Atropine and other medications for heart and stomach conditions
  • Medication for Parkinson's disease, Xanax and other drugs that affect neurotransmitters
  • Dramamine and other motion sickness treatments
  • Botox

Does Vaping Dilate Pupils?

You may have noticed our list of drugs that dilate pupils is missing some of the most common drugs people use, such as alcohol, caffeine and nicotine. While both alcohol and caffeine have been noted to dilate pupils when consumed in excess, vaping or smoking cigarettes can have the opposite effect, constricting the pupils and causing what some know as “pinpoint pupils.” 

Does Adderall Cause Pupil Dilation?

It can. Adderall is a common prescription medication that's a mix of amphetamine and dextroamphetamine and is considered a stimulant helpful in the treatment of ADHD and similar conditions. It causes mydriasis, where the iris muscles relax and dilate the pupils.

How Should I Confront Someone About Suspected Drug Use?

If someone you love is using drugs, it can be challenging to know how to talk to them about it. Many people who misuse drugs are ashamed or feel guilty about doing so and, therefore, are likely to change the topic or lash out when it comes up in conversation. Still, confronting them can save their life and give them a chance to get the support they need — even if they don't recognize it themselves. If you're planning on talking to someone about their drug use, try to:

  • Stay calm: Talking about drug misuse can be an emotional conversation for anyone, especially the person being confronted. Responding with your own emotions can escalate the situation and turn it into an argument or something worse. Staying calm makes it less likely your loved one will feel attacked and allows you to better listen to their own concerns and story. Understanding is the first step to starting this healing journey together.
  • Have a plan: Before entering the conversation, come up with what you want to say and practice it. You can even write it down so you remember everything. This can help you keep calm and on track if things do escalate. You may also want to consider how your loved one is likely to react and come up with a few ways to adjust.
  • Bring a support system: With your help, this person won't have to navigate their addiction alone. But remember that helping them through this is not on you alone. You both need a community that can help you through this time, and you can show that network to them from the very beginning. If you're nervous about approaching them alone, connect with other people who care about them and see if they're willing to assist you in this situation. You can also reach out to a professional to have an unbiased party who can help you through this emotional situation.

Treatment Options for Addiction

Dilated or constricted pupils are often minor and lesser-noticed symptoms compared to other signs of substance use. Addiction can bring with it lifelong struggles that persist long after a person stops using substances, but the likelihood and severity of these issues can lessen the sooner you or your loved one finds treatment.

Diamond House Detox is a rehab facility in Sacramento, CA, that specializes in inpatient treatment, outpatient services, detoxing from drugs and dual diagnosis care. Our medical staff knows how to work with you on your addiction and find a path to recovery that works for your specific situation.

How We Treat Addiction

Addiction is a complex and ever-changing field, and our treatment options reflect that. Each client who comes to us for treatment gets their own personalized treatment plan with input from our therapists and psychiatric professionals. We welcome our clients and those who love them to learn as much as possible about every step of our process to enhance understanding and encourage collaboration. Recovery is a long path, but walking it with a strong support network makes it much easier to navigate.

When a client comes to Diamond House Detox, they'll go through an intake process that helps us determine where to get started and the level of treatment necessary for their particular addiction. They will likely go through:

  • Detox: Detoxifying the body from any drug is often the most challenging part of getting sober and is the very thing that keeps people from going into recovery. We can take away some of the strain of this process by welcoming clients into our facility and giving them the support of our specialists and medication to help prevent serious complications while slowly weaning their systems from the drugs.
  • Individual therapy: Addiction comes from somewhere. Our licensed therapists will work with clients to get to the root of addiction and understand how they can keep themselves from relapsing in the future.
  • Group therapy: Recovery does not have to be a solitary battle. Along with our care team, clients meet with others going through similar struggles and learn from them as they work on getting better together. Our group therapy sessions offer unique insights into new perspectives and another layer of support to encourage recovery.
  • Psychiatric evaluation: Though many of our clients come to us for addiction treatment first, they may also be dealing with a co-occurring disorder like depression or OCD, which fuels the drug or alcohol use. We believe that to treat one condition, it's necessary to confront both, which may involve prescribing medication and long-term therapeutic care.

Let Diamond House Detox Help You Start the Recovery Process

Here at Diamond House Detox, we provide individualized care with a focus on co-occurring disorders in our home-like environment. No matter the substance, we can help you start the process of recovery. With treatments based on your needs, you'll have the dedicated care and aftercare plan you require to move forward with your life — whether it's a 7- to 10-day detox or up to 30 days of intensive inpatient recovery.

If you have any questions or would like to learn more about our programs, be sure to reach out to us today.

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Psychiatric Mental Health Nurse Practitioner at Diamond House Detox
Vicky is a board certified Family Psychiatric Mental Health Nurse Practitioner, certified by the American Nurses Credentialing Center. She began her nursing career in healthcare by working in the intensive care unit, and then an inpatient psychiatric hospital. After realizing the mental health needs of both the patients and the families she served, she became a Psychiatric Nurse Practitioner. Throughout her experience working with clients, she has developed a passion for those with dual diagnoses and specializes in helping individuals recognize the issues driving their substance use. This recognition has been crucial to the individual’s success in treatment. Vicky opened Diamond House Detox so that she can address these issues early on in a therapeutic environment to allow clients to transition to the next level in their recovery.
Vicky Magobet
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