Rapid Diagnosis: Pinpoint Pupils

Abnormally constricted or “pinpoint” pupils are a great finding for our rapid diagnosis series. There are many things that can cause the pupil to abnormally dilate. Very few things will make the pupil abnormally constrict. Constricted pupils are a doorway to a very short list of ailments and with a bit of background you should be able to hang your hat on one fairly quick.

How do we assess for “pinpoint” pupils?

Recall that the pupil should be mid-range and reactive under normal lighting conditions. When subjected to bright light, the pupil will constricted to reduce the volume of light entering the iris. In darkness the pupil will dilate to allow as much ambient light in as possible. Pupils smaller than 2mm in diameter under normal lighting conditions can be considered “pinpoint”. Any pupil that responds to changes in lighting conditions with 1mm of movement or less can be considered minimally reactive or nonreactive.

To assess for pinpoint pupils we need to subject the pupil to darkness by asking the patient to close their eyes or covering the patients eye. When we return the light source to the pupil we expect the pupil to be larger and rapidly return to its original size. If the pupils remain <2mm in diameter through the changing light conditions we have a “pinpoint pupils” finding. The fancy medical term for this phenomenon is abnormal miosis.

If the patient has bilateral pinpoint pupils consider the following possible etiologies:

1.) Opiate use / abuse / overdose

Opiate class drugssuch as Heroin, Fentanyl, Codeine, Methadone and Morphine stimulate the parasympathetic side of the autonomic nervous system and cause pupil constriction. While it varies depending on your response area, most of the constricted pupils that you encounter in the field will be opiate induced.

Look for possible sources of drug use or abuse from prescription meds to illicit drugs. Evaluate the patient for track marks across the veins and the scene for paraphernalia like spoons, tin foil, matches, syringes and makeshift tourniquets. Don’t rule out opiates in pediatrics. Miosis in combination with depressed respirations are the hallmark signs of opiate overdose.

It’s also worth mentioning that if you happened across this page looking for information about opiate addiction, there are good people who can help you overcome the challenges of opiate withdrawal and addiction recovery. Now let’s get back to our list.

2.) Pontine Hemorrhage

The pons is a knob-like structure located at the front of the brain stem. Intracranial hemorrhage in the area of the pons will typically cause bilateral pupil constriction. Intracranial hemorrhage can have both traumatic and atraumatic origins.

Consider pontine hemorrhage in the presence of high mechanism head trauma and patients with a history of vascular disease, strokes and abnormal bleeding. If you find miosis with altered mental status that does not respond to Narcan administration, consider the possibility of a pontine hemorrhage.

3.) Organophosphate / Chemical / Nerve Agent Exposure

There are a few classes of chemicals that cause parasympathetic over-stimulation and, therefore, pinpoint pupils. Organophosphate chemicalsare the most common. Virtually any phosphorous-containing organic compounds are considered organophosphates.

These compounds are effective pesticides used in agriculture. They are widely used because they break down easily in the environment unlike their cousin DDT. Malathion and parathion are examples of organophosphate pesticides. These chemicals kill insects by disrupting their nervous system function. Unfortunately they kill humans in the same manner.

They can be absorbed through the skin, inhaled and ingested. Once absorbed they shut down acetylcholinesterase production and put the parasympathetic system into overdrive. This will create the classic SLUDGE presentation, characterized by excessive salivation, lacrimation (tears), urination, defecation and emesis. And two other telltale signs (If you needed more) … muscle cramps and pinpoint pupils.

Many of the never agents used in terrorist attacks are organophosphate in nature including Sarin and VX gas. If your patient is involved in farming or agriculture, drank an unknown chemical or was a victim of a chemical attack, check for pinpoint pupils and consider organophosphate poisoning.

So there you have it. OK, sure, we’ve left out a few possibilities here. Hopefully you’ll forgive me for passing over Horner’s Syndrome, Neurosyphilis and a few other obscure brain abnormalities that will cause abnormal pupil constriction. No diagnosis is a certainty, but when you find those pinpoint pupils, start with the big three. Now go look at some pupils.

Related Articles:

Five Assessment Findings That Should Concern You

Understanding Combative Head Injuries

What Is Nystagmus?

Five Trauma Scene Mistakes You Should Avoid


  1. Alan Johnson says:

    Steve, thanks again for posting this stuff on the web so students and experienced EMTs alike can all learn from this site. I really found this post helpful especially for Medical Assesments where origin may not be so easy to find as being ejected from a vehicle. Thanks again Steve and it was fun to watch ya get tied up in class tonight.

  2. Steve Whitehead says:

    Hey, your welcome Alan. And I’m glad I could be an adequet, if unplanned, substitute for a combative patient for the class.

  3. thanx

  4. great info, but please spe;ll correctrly:

    neuorsyphilis not neurosyphilus

    and pontine not pontiene

  5. Steve Whitehead says:

    Thanks Dr. P. I have corrected both errors. I appreciate your editorial heads-up.

  6. Steve Whitehead says:

    @nony You’re welcome.

  7. Insha rafia says:

    I was able to get whole information about the topic from here which I could not find anywhere…

  8. Gail Batton says:

    I am a TLE pt w/long post-ictal times where I can hear, feel, but cannot talk, move, respond. I have, right now, a lump and bruise from repeated sternal rubs that I felt but was unable to respond to. Vitamin A – ammonia under or UP the nose does not work and with COPD, it is very disturbing. My eyes are the first to “come back”, speach comes back as “moaning”, legs/arms can take 12 or more hrs to come back. Full, normal speach, can take up to 24 hrs. THIS IS REAL – documented. Laughing, talking psych, etc. may anger me, but I cannot tell you that – because I cannot talk. I take MANY epileptic meds and no psych meds and live a facility because of the epilepsy, COPD, CH, PVD, etc. 2x I had “grand-mal” and “coma” from low potassium and once from low magnesium. My seizures began when I was 18 mos old – same as now – staring, stiffening, going limp and unresponsive, then poof – back to reality with amnesia for the event. PLEASE TRAIN YOUR EMT’S FOR POST-ICTAL/ICTYL STAGES and the various TYPES of epilepsy. My vitals are usually normal – just unresponsive due to epilepsy – NOT psych. Thank you. God bless you.

  9. clayton says:

    thanks mate, you learn something new everyday. i never realized opiate could cause pinpoint pupils- rather, i always thought they dilated them like most other drugs. again, thanks

  10. As I found out last night, theres one more thing that can cause pinpoint pupils: SKUNK SPRAY. One of my dogs got a load into her eye and that eye constricted to pinpoint within a couple minutes. I did the usual skunk wash (Dawn dish detergent, baking soda and hydrogen peroxide) around her eye, then tried irrigating her eye with water, but that was difficult. As it was evening, she bedded down for the night and about an hour after the incident her pupil started growing slightly. By morning it was normal and her eye looked fine. She had no irritation or watering in the eye either.
    Now – what skunk spray contains to do that is beyond me, however it may have evolved as part of the defense mechanism as when pupils constrict – you cannot see and the skunk escapes the predator.

  11. Really.thanks on greate information

  12. Just found your site today while resting after a gastro- bug bite. Am in process of renewing my teaching certification for EMT after several years of just practicing medicine as a PA. I am very impressed with what I have seen of your content, and plan to make your site required reading for future students. The Pinpoint Pupil article is a classic in that it puts all the emphasis on constriction without mentioning dilation to any degree. As a result the confusion that often occurs to a student is avoided, since the issue of dilation can then be implanted in a separate class or article. Thank you for your perspective on 3 minutes, 3hrs, 3 weeks. That is a classic also, and one that must be impressed from the very first class to all potential EMS students.
    Keep them coming

  13. i have big time pinpoint pupils and they rarely dialate. it is always small and never gets big, i wonder why

  14. ZUHEER ophthalmology says:

    Excellent info. It is hard to find such info in ophthalmology texts

  15. Hey, I wanted to delve into my 1mm diameter constricted pupils from last night to 12 pm this afternoon. It was caused a stimulant, though. Concerta (methylphenidate) to be exact. Im not a crazy druggie or anything, but I do realize that I took 216 mg of concerta xr all within 20 minutes, and it caused slight paranioa, intense heart beat, and unbalanced depth perception (because if i looked at my laptop, it seemed like it kept shifting). Just wanted to help out.
    P.S. I was planning on taking 150 mg which is double my dose, and i wanted to seewhat would happen. I failed at keeping track though XD. NOT DOING THAT AGAIN!

  16. Question for the author.
    My 3 year old had what seemed like possible multisystemic reaction last night with dyspnea/tachypnea/tracheal tug/intercostal and below costal retractions. Along with flushing and new rash. He has a history of anaphylactic reactions that resolve with epi/benadryl/ventolin, and or selfresolve. Gave ventolin as didn’t seem epi worthy. And went to pediatric walkin for further assessment. Was trying to avoid Emerg as we go there far too often and they seem to think the problem is my overseeking healthcare rather than problems with the little one.
    Saw a pediatrician, my son had fallen asleep en route. Asleep for maybe 1/2 hour. Heavy sleep, it was about 7pm. Doctor and I couldn’t rouse him, but he tends to sleep heavy. Doctor said his pupils were miotic, that he was unresponsive, didn’t think he was sleeping and sent us by ambulance to emerg.
    Once in ambulance my son woke, very irritable and pale, eyes back to normal. Doctor had said coma or intoxication. By arrival at Emerg my son was bouncy and back to normal but a little hivey so eventually we were able to get Benadryl into him. When he fell asleep we noted his pupils again tiny and unresponsive, showed the nurse who thought also it was abnormal. Doctor did not witness this.
    Bloodwork and chest xray normal. We were discharged with no follow up.

    Is this normal? Our GP says ventolin can cause miotic pupils, and in sleep its within the normal range.

    Would you please be able to answer my question? If possible could you email me?

    Thanks very much, Colleen (very worried parent)

  17. administrator says:

    Colleen, I’ll e-mail you.

  18. thank uuuu

  19. Went to optician at Xmas he found and diagnosed with pin-point pupil that small he didn’t have a drop to open it, unfortunately for me I have extreme light sensitive seizures, which makes it difficult for eye examinations with light. I have never taken opiates. Allergic to morphine

  20. i have seen a 32 yrs old man, complaint of neck stiffness and not well for a day,and then can’t swallow any kind of food or liquid happened and progressive in a day. can tell name and places well, drinker b4 night he drink and then fall asleep, can’t open mouth widely, muscle spasm on stimulation , better to think as tetanus though no history of remarkable injury noticed. but has pinpoint pupil, no history of drugs, sweating and aspiration . what’s opinion?

  21. Anonymous Spell Checker says:

    Dr. P., did you really type “please spe;ll correctrly?”

    You can’t even spell the word spell or correctly yet you are telling Steve how to spell?


  22. Thank very much
    I’m medical student and accidentally found this site while i search an answer for my exam .The blog is written easily for understanding as I’m not native English.

    This website is very useful.

  23. Just had a quick comment in regard to organophosphates / nerve gas, and scene safety. If at anytime you are approaching a scene and see more than one person doing “the floppy fish” as I refer to it (Seizing, foaming at the mouth, vomiting). STOP! Do not go any further and get the hell outta there! Next, go ahead and get your “Mark One” kit out and ready to use.. ON YOURSELF. First off, anyone at that point is basically already gone. And even if one of those victims had a chance of living, by the time someone has absorbed enough nerve agent to cause these symptoms it would seriously take all the atropine and pralidoxime you have on your truck and all the hospital has in stock… That is assuming the person is alive by the time they get decontaminated, and transported to the hospital. Remember the mark 1 kits on the truck are for YOU! Not the patient. If you are sick you can not help anyone, and you now take up man power to save you.

  24. dr:ayman says:

    is cns infection can cause pinpoint pupil

  25. Anonymous says:

    I have a friend that only has a pinpoint pupil from time to time, he used to take heroine but the exam shows negative even when he has the pinpoint pupil. It has been weeks since the last pinpoint, but yesterday i saw his eyes and they were pinpoint, even in the dark they stayed the same he swears he hasn’t taken anything and i was just wondering is there another reason, other then drug use?

    I’m so completely lost and confused, i don’t even know what to believe anymore..

  26. Dee Humbles says:

    For Dr. P – Neurosyphilis was spelled correctly – you spelled it wrong BOTH times…and several words in your post were spelled incorrectly.


  27. Jack Cardel says:

    I’m afraid your list wasn’t very helpfull if one is not a drug-user.

    Various eye diseases cause constricted pupils or pinpoint likely used by law enforcement. If they used this list everyone over 65 would be senior suspect. A list of constricted pupil diseases and one does not mind who is looking. We must not consider all inquires drug addicts. This is a valuable tool for techs and doctors who are not necessarily in the know. Most opthamologists that do not do much surgery automatically are put back by the patient thinking they are addicts as soon as the see the police term, “pinpoint.” Most eye diseases or problems can and do show pinpoint or rather constricted pupils; Endothalmitis, Exogenous, Strabimus, endogenous, Endophthalms (severe pain, dreaded disease, possible blindness and loss of one eyeball if pain persists. Eye ball reseeding into orbit and breakdown of bony-step (bone below eyebrow, Pineal gland disease, Brain tumor, very low blood pressure 80/54 etc., continued

  28. BrokeBackMom says:

    I have a broken back and am in the middle of experimental surgeries. In the meantime, I am a walking nerve ending! lol ~ I have tried almost every opioid for pain. I finally discovered the Fentynal Patch. It is actually relieving my pain after four years of torture. My concern is that the dose may be too high. Prior to Fentynal, I was taking 8-10 Norco per day… 2 at a time, every 4 hours. After a year, they just didn’t work anymore. I was just going to go off of them all together and deal with the pain and not risk liver and kidney damage. However, my pain management doctor introduced me to this patch. She put me on 25 micrograms per hour; this patch is a 3 day patch. Sometimes the patch is stubborn and it does not stick to the skin. Last night I went to change my patch. Again, the patch became stiff and fell off. It’s very dangerous to touch those, so I immediately flushed it down the toilet, as instructed by the FDA and my doctor. I put on another patch, and this one is sticking better than the other one. After I put my patch on, I started to have some pain in the 6-7 range. I am instructed to take Norco for “breakthrough pain”. I took one, and I was fine. This morning I woke up and I was in pain still. I took a Norco… approximately 12 hours from the last Norco I took. Within 30 minutes I was feeling very euphoric. Heavy eyelids, not clear thinking (and I am studying for finals right now!), and a stiff neck. I looked at my eyes and I seem to have pinpoint pupils. Obviously from the combination of the Norco and Fentynal. However, my question is Now What?! I am a little scared. My heart beat is fast. I do suffer from anxiety, but I am not allowed to take anxiety meds with Fentynal. I get scared easily when it comes to Rx drugs. I feel like time will help to bring me back down to earth. But, is there anything I can do to reverse these side effects? I thought about taking the patch OFF, but that would be another waste of another patch and my pharmacy is so mean to me, thinking I am giving these patches away when really they are just made shitty and don’t stick. I saved them and HANDED THEM TO MY PHARMACIST. I am scared of them harassing me, as they do often to me and every other customer at Walgreens, so I don’t want to take it off. But, on the other hand, I don’t want to O.D. either. I’ve been feeling crappy for about hours. I need to be productive and I cannot in this state. I have a to-do list a mile long and a six year old who wants to play at the park. What can I do to reduce these side effects? And, what should I look for when debating whether or not this is an emergency situation and perhaps discard the patch and head to the ER, or just sweat it out? Thank you very much. D.

  29. @Jack. I disagree with you Jack. My list is extremely helpful to the prehospital providers to whom it was written. It may not be as helpful to an ophthalmologist specializing in atypical eye abnormalities. My last paragraph addresses your concern. Nothing in my post suggests that we should consider everyone with pinpoint pupils “drug addicts” . You’re bringing your own bias regarding the term to your response. Your statement that everyone over 65 would be “suspect” is patently false. I also contest your statement, “Most eye diseases or problems can and do show pinpoint or rather constricted pupils.” Some fairly uncommon eye diseases might cause abnormal constriction. This is interesting and of some use to prehospital providers, however, in this context, it would only confuse the subject.

  30. @BrokeBack Please see my post regarding looking for medical advice on the internet:


  31. marchelle says:

    I just had a shop vac (I bought fom a garage sale then used to suck out the drain of my dishwasher) shoot a bunch of crap into my eyes. I flushed them for 5 minutes with tap water then 10 minutes with contact solution. They are red and burning (maybe from irritation). I can see but it gets fuzzy from time to time as if mucos were on them (but they are dry). My pupils are even and super constricted. The stuff in the wet vac was black full of unknown particles and liquid. I am not sure what to do besides flush them.

  32. I’ve had iritis/uveitis in both eyes for 5 years which caused both pupils to be stuck at pinpoint 24/7. I’ve had to use pred forte, durezol and betimol for several years for continual flareups. I was told the steroid eye drops while absolutely necessary would speed up cataracts. Once cataracts were bad enough to require surgery stretching the pupil could be done at the same time. I had cataract surgery July 1st and my surgeon was able to stretch my pupil. It certainly does not look normal but at least it is bigger and will dilate. I also experienced horrible anxiety and was extremely jumpy and nervous especially during sunset. I always wondered if my extreme nervous reactions had any relationship to pinpoint pupils. All my doctors said no. Well since I now have one eye that will dilate, can see contrast and does not have a blurry moon in front of it I’m no longer a nervous wreck. Should I wear some type of medical ID bracelet so an EMT does not assume I’m an opiate user? My other eye is still pinpoint but the cataract is not that bad yet.

  33. HI. An orthopaedic surgeon wrote a report about me regarding orthopaedic matters. He also included in his report that my pinprick pupils showed drug use. However I dont use drugs, but had been raped just a few hours before my appointment. I would like to know if the shock (caused by the rape) that was so recent, would have given me pinprick pupils.

  34. administrator says:

    No. Shock, clinical or emotional, does not present with pinpoint pupils.

  35. Robin Short says:

    Last night I was not feeling well. I had a dull headache. As the evening went on my vision became blurry and I could not make my eyes dilate. Also I noticed that I had no perrephrial vision in my right eye. I also became nauseous and dizzy. Any ideas. This happens every once in a while.

  36. Charlie says:

    I have chronic pain from having 2 stomach surgeries and post dvt. My doctor gave me the fentanyl patch I had to take it off at work yesterday I had it on for 20 hrs I was up all night my brain was dead couldn’t think straight kept forgetting what I was doing my pupils were pin point I had hives, my head was pounding nose was bleeding. I started gaging got sick. When I got home I shower made myself eat took 2 advils and 1 norco.
    My right leg went back to hurting and cramping all night woke up this morning and have all my normal
    Pain back.
    The patch did take the pain away but I had to bad of reaction from it.
    I will call my doctor on Monday and let him know what happened.

  37. There’s another very common but not widely known cause of contricted pupils: benzodiazepine withdrawal/discontinuation. I was prescribed klonopin 2 mg/day for 10 years. Upon discontinuation, I had constricted pupils for 8 weeks.

  38. Mother-in-law recently been prescribed pediatric dose of morphine for end-of-life care. Is it possible even this small dose could cause the pinpoint pupils? Also a history of TIAs – I suppose either could be causing this eye condition? Great website, thank you.

  39. Even a very small dose of opiates can cause constricted pupils, as there are three aspects to medicine dosing – Ingestion, Metabolism and Exretion. If your mother is on end-of-life care it is very possible she has an ellement of renal failure, and as such isn’t excreting the morphine as normal. This would result in accumulation of the Morphine in her system.


  1. […] neurological evaluation. Note the size and shape of the pupils including abnormal constriction (pinpoint pupils), dilation, inequality or nystagmus. Assess for hemiparesis from head to toe and check distal […]

  2. […] produced most of the body of his work while on opioids. There are files of photos of him where his pupils are pinned (abnormally constricted). I’ve looked it up online and this goes way, way back. Pinned pupils […]