Caffeine Allergy: Top 20 Symptoms

Allergic to caffeine? It seems like you aren’t alone as hundreds of people have now testified to strange reactions experienced after caffeine consumption.

This article has been compiled from anecdotal evidence. Some people do not metabolize caffeine as well as others. Others are also sensitive to adrenalin. It pays to know your limits with caffeine. If you suspect that caffeine is causing problems, this can be tested by eliminating it from the diet.

Some time ago, we published a short post about the possibility of allergic reactions to caffeine.

That post received hundreds of comments from those who claimed to have experienced some type of adverse reaction to caffeine.

We have painstakingly sifted through all those comments, compiling the top 20 caffeine allergic reactions in order from most common to least common.

In most cases these symptoms were reported after only having a little to moderate amount of caffeine through coffee, tea, soda and/or energy drinks.

Most Common Allergic Reactions to Caffeine

  1. Skin problems such as hives, eczema, rashes, acne, severe itching
  2. Headaches or migraines
  3. Anxiety and panic attacks
  4. Can’t focus or concentrate
  5. Tongue, glands, or throat swelling
  6. Heart racing or palpitations
  7. Angry, irritable, bad mood
  8. Fatigue
  9. Dizziness
  10. Extreme jitters
  11. Chest Pain
  12. Depression
  13. Numbness in face, hands, or feet
  14. Muscle pain
  15. Shortness of breath or tightness of chest
  16. Delusions or hallucinations
  17. Flu/ cold like symptoms
  18. Vision problems
  19. Cold sweats
  20. Eyes swollen shut
Need to quit caffeine? Get expert help here.

Is this Scientific Evidence?

At least one scientific study has shown that people can have anaphylactic reactions to caffeine and is confirmed by a skin prick test.1

There is evidence regarding the inability to process caffeine as some people lack the genes responsible for this or the genes aren’t being expressed as they should be. This allows caffeine to build up in a person’s body rather than being broken down properly. These people are described as hypersensitive to caffeine.2

The above data is entirely based on anecdotal evidence, so don’t take it as gospel or scientific, but rather consider these caffeine allergy symptoms as possible since they were reported by a large number of people. If a person suspects a caffeine allergy, he/she should cease caffeine consumption immediately and then assess as to whether it was indeed the caffeine. The symptoms should subside  after caffeine is eliminated.

Did you know that rutaecarpine can remove caffeine from your system faster? Find out how here.

There is a fine line between what would be called caffeine sensitivity and what would be called caffeine allergy, but overall we’re dealing with the body not being able to correctly process the caffeine molecule, so whether it’s called sensitivity or allergy is up for debate.


Skin rashes are common.

Most people on the original article reported several of the above symptoms and some of the caffeine allergy symptoms were quite bizarre. The symptoms that were the strangest included itchy ears & anus suffered by one poor soul and a sweaty butt crack reported by another…

Caffeine allergy has also been linked to a form of ADD and dementia in adults. The claim is that caffeine induced anaphylaxis impairs people’s abilities to concentrate and remember things. (Src.)

Could It Be Mycotoxins?

Mycotoxins are essentially chemicals produced by fungi and they can produce all kinds of negative reactions when ingested by humans. A recent study3 from the University of Valencia in Spain found that commercially sold coffee is often contaminated with mycotoxins. They’ve identified 18 different mycotoxins that are commonly found in coffee and found that the levels in decaffeinated coffee are often higher than that of regular coffee.

If you have a reaction to coffee but not other caffeinated products, there’s a good chance that you are sensitive to mycotoxins and not the caffeine.

What To Do If You Are Suffering

  1. Explore our extensive Caffeine in Food database as well as our Caffeine in Beverages database in order to be aware of all the products that have caffeine listed as an ingredient along with the amount they contain.
  2. Eliminate these products from your diet. There may be a period of caffeine withdrawal where you actually feel worse.
  3. Assess whether your symptoms have disappeared. It may take up to 2 weeks for all of caffeine’s effects to wear off. 

Please note: A surprising number of products contain caffeine, and some have a lot more than what you think.

Even decaffeinated drinks still contain caffeine – although only a small amount such as decaf brewed coffee.

Education is best way to prevent an allergic reaction to caffeine.

Get Help Quitting Caffeine

Reduce your caffeine intake without pain and discomfort.

See our new 10-step plan
  • Jenny

    I feel very strongly after reading this that I’m on to something. I had wondered about a caffeine allergy but had never really heard anything about it before. I have noticed for at least the past ten years or so that I would feel worse on days that I had chocolate, tea or caffeine soda. It’s been getting worse over the years, especialy the itchy ears and swollen eyes. I will stop all caffine and see if I get better. I have the itchy skin/ears, rash that looks like this picture, mood swings(an hour or so after eating/drinking caffeine), panic attacks, edema of face/hands feet and brain fog – just to name a few that bother me the most.

  • Elizabeth

    I developed hives last week for the first time and they got progressively worse over 3 days. I’ve always been “sensitive” to caffeine (makes me feel sick and uncomfortable) and only drink one cup of coffee a day and this plus the occasional Milo and a few squares of chocolate occasionally is my only (known) source of caffeine. I stopped drinking coffee just to see if that is what it was and have had no real problems for the last few days. Its just when I get warm eg after a shower and in bed at night I have a few little spots come up – right now the palms of my hands and soles of my feet are driving me mad! Can anyone tell me if this is normal after an outbreak (my outbreak was all down my sides, my back and tops of legs and arms, and also ears and in my hair).

  • Lisa

    I am grateful for finding these posts about Caffeine Allergies. It’s been months since I’ve been going through hive out breaks and this whole thing was driving me crazy! The only thing to add any relief was taking Benadryl.

    Back in 2006 is when I had my first out break of hives. During the holiday season it started and it was rather mild cases of hives. On again and off again. Nothing I couldn’t handle and Benadryl would subside the itching. I had no idea what was causing these hives and chalked it up to the cold weather. I have never, in my life, been allergic to anything eaten or drank. This stopped in 2007, 2008, and started up again in the later part of 2009. December to be exact. So, it’s been approximately 4 months now that I’ve been dealing with these hive out breaks.It didn’t matter what time of day nor did it matter what part of my body EXCEPT my face my hives would break out. They arrived every day but the itch was controllable with the Benadryl. About a month ago, mid February, 2010 is when I noticed them going to my cheeks and eye lids. One day my right cheek swelled up and more Benadryl was taken. As soon as my cheek swelled, my left eye did too. It took 2 days for my eye and cheek to get back to normal. Then started with the palms of my hands. They’d puff up so much that they would turn a dark red and they almost felt numb. If I touched or scratched them it would burn but feel sort of good at the same time while I itched. Then it escalated to my fingers. Different ones each day. More came behind my knees, the inner part of my forearms, bra line, in short, hot spot areas of the body. The only relief was Benadryl. Who can live on Benadryl, daily, when you own a business? So, I’ve been writing down my daily diet and going over what I thought it could be. I’d come on the internet to do research and ran across these posts but before I did, today, Thursday, March 18, 2010 just while sitting at my office I felt a slight tug in my left eye again. The other day it was my right eye and then right cheek….So today again my left eye became puffy and I knew to take 2 Benadryl. I drove home and by the time I got home, anyone could clearly see my eye was severely puffy. I sat and talked with my husband and we realized I’ve been drinking so much coffee and today alone I drank over 7 very large mugs of the very tasty stuff. Plus, had taken 4 water pills. Yes, I know, way too much caffeine.

    We pieced it all together and I really do believe I have a caffeine allergy or sensitivity. For years prior to all this, I was able to take Excedrin or a generic form of any aspirin/acetaminophen with never having a problem. It is only until a couple years ago when I started to drink a lot of coffee say around late of 2008 and really heavily drinking it starting in 2009. I’m thinking all the coupling of aspirin and coffee equals excessive amounts of caffeine and that is what is affecting me. An over abundance, for me that is.

    I’ve found some serious relief in reading all of your posts and thank you for posting your ordeals. It’s not something any one ever wants to share but all your posts reached me and it helped piecing this all together. I hope others reading this they too can find some relief and knock off the coffee to see if that is what is causing their hives.

    I have decided to completely rid myself of any coffee, and see how that works. If it’s a simple elimination of a drink to rid my body of these daily hives, then I’ll do that! I’m too vain for this to be affecting my face.

    I’ll keep everyone posted if this is what the problem really is. No caffeine!

  • Jenny

    I posted back in March when after reading this site I thought maybe caffeine was my problem….Well,IT IS!!! I’ve been completly off caffeine for two months and I feel my health is getting stronger and better everyday. I was at a baby shower party a week ago and had just a tiny piece of chocolate cake and within hours ALL my symptoms came back and I was miserable for two days. Only some time and alot of water helps to get it out of my system. I am soooooooooo happy that I finally know what’s wrong, after more than 10 years of suffering!!!!!!!!!! Everyone PLEZZZZZZZZZ give this a try and get off caffeine if you are having these problems….it is so worth it!

  • ted

    Jenny-A small piece of chocolate cake would have hardly any caffeine in it unless they used coffee as a flavoring.

  • Jenny

    Ted – I understand your point, however, depending on how severe an allergy is, sometimes it only takes a very small amount to produce symptoms. This cake had very thick fudge icing on it.
    From what I’ve recently learned caffeine builds up over time in the body, just like other drugs and has an accumulative effect. In the last two months of reading everything that I can get my hands on about this I have discovered that it takes months and months to completly get caffeine out of your system assuming you’ve stopped consuming it. Believe me, these symptoms are unmistakable and could not have been caused by anything else. I’ve been dealing with these symptoms for a little more than ten years and the only thing that I recently took out of my diet was the caffeine.

    On another note, to all that would be interisted…I have discovered something that does help reduce the effects of caffeine in the body. It’s called L-Theanine and it’s an amino acid that ironically is derived from green tea.

  • Hippo

    Omg, I just had an energy drink to help me wake up and do work, it’s called “Focus energy shot”, and my face is itching and it’s red as a tomato, my elbows are numbs and itching, some parks of my body started to itch, and my neck is itching also. I also think that my left eye vision is worse, and right ear listening has also worsened. And a terrible headache. I just took some antihistamines, and waiting what happens next.
    I wanted to take one of these before my exams next week, so I would be more energetic.. and just decided to test how it works today.. Obviously, I’ll never use it again, this synthetic, disgusting thing!!
    Lesson to learn here: use natural things, even strong coffee with sugar wouldn’t do as much harm as this.
    Bottle contents (“Focus Energy Shot”): Vitamins: Niacin(B3): 30mg (167% RDA), Vitamin B6: 40mg (2000% RDA), Vitamin B12: 500micro gram(50 000% RDA), Folic Acid 400 micro gram (200% RDA).
    Oh, I just noticed, on the bottle it says: “…Niacin can cause temporary increased blood flow near the skin, resulting in redding and a hot flush”.
    But this is not normal. DO NOT USE IT!

  • Gioconda

    I am so glad I have found this site. After I have read everyone’s posts, it was like reading my symptoms’ chart for the last ten months. I have been absolutely miserable with mystery ailments that plagued me continuously and which the doctors were unable to pinpoint. In August last year, I have developed a seemingly innofensive rash on the back of my thighs, near the skin folds. I never gave it a thought until I saw that it progresses, that it also triggered my eczema (which I stopped having since my teenage years) and that it begain to severely affect my face. My eyes would swell shut and my entire face would go red, blotchy and puffy. I went to the emergency twice, both times was given anti-allergy medication, like benadryl as well as cortisone (once in the form of intravenous – prednisone, but mostly in the form of creams). I went to dermatology and allergy doctors, but none of them wanted to go beyond the manifested symptoms – eczema and urticaria – and continued to insist on steroids and histamine blockers. As none of these «band-aid» solutions helped for any amount of time beyond the indicated relief period (24 hours or so) and knowing the devastating long-term effects of corticosteroid drugs, I began to investigate the source of the problem.
    You see, I never was a coffee drinker, having an occasional cup in a blue moon; but, chocolate, on the other hand, and in the last 15 years or so, dark, high-cocoa content chocolate was my constant companion, my best friend and an indispensible food staple. I suspected chocolate, but I did not really wanted it to be the culprit, so I continued to eat it. I went on a dairy and wheat free diet for two weeks, but the symptoms continued unabaited. And in the last month and a half the symptoms got so bad that I was ready to kick not only chocolate, but also bread and dairy for ever. I was plagued by a red rash that had raised bumps which itched and would appear mostly in warm places (like in other cases described on this site) – inner thighs, top of thighs, belt and bra line, bikini line arm pits and, like someone else mentioned, on my bum as well. Then it also started to appear on my arms and neck affecting my face and eyes to boot. I was living on Reactine, Aerus and Benadryl alternatively and, as much as I hated it, on cortisone creams.
    And what can throw sufferers for a loop is the fact that once an allergic rash starts, it does not go away by itself, it needs to be deactivated by anti-allergy medication and even then, it can come back for days on end, although in a weaker form. At first, I thought, it cannot be the chocolate because a week would pass without it and I would continue having some red bumps, but now I know that it takes time to rid the body of caffeine. I also, I now realize, was drinking black tea which is enough to continue the allergic reaction.
    I have now stopped all chocolate, caffeinated teas, coffees, chocolate deserts, etc. and will see how that goes. I am almost positive that caffeine is the culprit. My gastroenterologist said that it takes about three months for a food allergy to completely clear the body.

    So don’t despair, persist, take anti-histamine tablets to help the body deactivate the rash, drink lots of water to flush the system and eventually, I am sure, it will disappear. I will wait two months and report on my progress to let everyone know the result.

  • It is now the second time I am having severe hives (eyes very swollen, can’t bend fingers much). The caffeine definitely builds up. After having them for months the first time, I figured out what was wrong, and consumed no caffeine for a year. That cleared me out for a year or two, but lately I’ve been drinking a lot of caffeinated soft drinks, and now it’s back. Annoying thing is I never drink coffee, and just drink things like Dr. Pepper and Mountain Dew cause they taste better than Sprite, etc.

  • Andrew

    Today was the worst day of my life. Ive been drinking coffee throughout college to help me maintian focus in class. I experienced some of the symptoms before today such as a rash after coffee or increased heartbeat, however today was a different story. After having two sips of coffee and throwing it out after a sick feeling in my stomach,I began to become delusional and my classroom began to shake. I managed to endure the whole class even though I was sweating and had blurred vision. After my class I had to wait 45 minutes for my ride home so I wandered around my campus. Every step I took my feet felt heavier and I began to feel more dizzy. The hallways in the buildings I was in seemed endless and I was losing touch with reality feeling anxiety as I passed each person who I believe to be staring at me. I then had an overwhelming anxiety attack which forced me to sit on the ground so I wouldnt pass out. I suffer from panic attack disorder so I thought it was a normal attack but the symptoms did not subside. After my ride picked me up I couldnt keep my eyes open on the car ride home because I was getting motion sickness. All I could think about was getting home and going to sleep. When I got home my eyes were glued open and I continued to experience these symptoms for a few more hours until I finally flushed the caffeine from my body by drinking tons of water. Today is probably the last day I will ever drink a caffeinated beverage again.

  • Paige

    I used to drink coffee all the time until about a year ago. I drink it and about an hour or so later I get hives and all red and itching all over. Not only just coffee but all the caffinated drinks I used to stay alert. Now, I drink decaf coffee and things like that and it has no effect. I don’t like the decaf as much, but its something that you have to adjust to when you have no choice.

  • Kelly

    so helpful in reading these comments….was treated recently for dermatitis (2X over course of last 4 months). creams, antibiotics, steriods, still comes back. I drink alot of coffee and sodas and it finally clicked, checked internet for caffeine alleries and “presto” I fit the mold perfectly. Will try (even though it will be touch) to leave caffeine out of my daily routine!

  • Haleigh

    I have one thats for sure landed me in the ER a few times its so bad

  • greendesigner

    I am a fellow caffeine sufferer. I discovered it ten years ago and it gave me rather severe systems, which masqueraded as acute anxiety for some time. I discovered my allergy by accident and have since researched it. Apparantly it has been known since the 1930s the effects of caffeine in some. Some affects can mimic mental health problems such as OCD, Schizophrenia, bi-polar disorder. With an estimated 30% of people in mental instituions mis-diagnosed as having mental health disorders which is really only a caffeine allergy.

  • Thanks for your summary of possible side effects of caffeine. I went on vacation a few months ago and just had water that week. I felt great… Your list seems to sum up a lot of what I’ve had issues with and I usually polish off between 20oz to a 2 liter bottle of soda each day.

  • Seun

    OMFG!! I love you ppl!!! i relate to everything you guys are saying. I messed up alot of things because of this. I was so difficult to control myself and my thoughts and my relationship with ppl man. I am a very optimistic person.It was really crazy, my symtops were a hell of alot of stress which had it own symtops like hair loss. I lost weight alot, depression, heavy panic attack(2 really embarrasing ones lol), attention deficit, i was alil hyperactivity, learning problems, chest pains (feltlike an heart attack), understanding informations was really difficult and speech problems. As a university student, memory problems is the worse thing you can have, cos i really didnt do as well as i wanted to. Also I became so insecure to a point where i was trying to find myself all of a sudden. I became so negative even when I get compliments from friends and family. I just didnt understand why I felt like that that. I tried so hard to make everything work, but it was like patching a broken eggs. It was definately the worse experience of my life. I dont wish this on any1. Its awful!.

    The sad truth is that alot of ppl died with it, and never knowing or get mis-diagnosed and some even sent to a mental institute and not being able to have a normal life… So Sad!. Ever since i researched was could be the problem with me, i saw sumthing about caffeine allergy and I research more able it, At that point I would try anything, So I went cold-trukey on caffeine, and I am finaally back to full health. Unlike any other allergy, Caffeine messes with the mind .We need to have a convention for this or sumthing.

  • jordanne

    WOW- I have been thinking for a while my problems were related to caffiene- now I realize that it is not just me. Thank you for sharing people!

  • MP

    Caffeine gave me severe panic attacks for years. It took awhile to figure out what was causing them. Also, I got such a bad rash on my face. It looked like a sunburn and no amount of scratching would alleviate it. My ears itched too. I used to have heart palpitations as well. I am now caffeine free and loving it !!

  • Theresa


    For many years I enjoyed drinking coffee with no problems. Two and a half years ago I starting drinking Dunkin Donuts (grind at home) coffee. Almost
    immeidately I starting losing my hair and breaking out on my arms, chest, and scalp. At one point it became so severe I thought I was dying. I had lesions on my face and my ears were so raw from rashes that they were seeping clear liquid. I was in so much pain. I saw over 13 doctors during this time period and no one could figure it out. They never asked me what I consumed or did. I also had allergy tests done that did not show anything. I went to alternative healers which did not help. I don’t know why I took so long but I finally prayed out it and out of my own personal agony I asked “please help me” About two weeks later I had a dream and I heard a voice tell me to stop drinking coffee and start eating onions in my food. I woke up and thought what a stupid dream. I did not listen to it. I told my husband about it and he said that as a child he would eat onions all the time straight from the garden. He and his family have lots of thick hair. Because I adore drinking coffee in the mornings I did not give it up. Several weeks ago I met a customer who asked what is wrong with your skin. That day my scalp was burnt red along with my sick skin. Not a good day. I told her that I have been sick for two and a half years and the doctors cannot help me. I told her that they said I may have Lupus on the scalp. She told me her bother was suffering the same way and he gave up drinking coffee and everything went away. I asked her “Are you kidding me?. She said once her brother stopped drinking coffee he went back to normal. I googled in caffine allergys and found this site. So last Wednesday I stopped drinking coffee. Today is Monday, six days later and the large rashes on my arms have gone away. The rash on my chest is ninety percent gone. My scalp is not red hot it is light pink. I am on antibiotoics from the my doctor for this rash. Now that I am not drinking coffee the medicine is working very strong. I want to sleep alot. Before this the medicine wasn’t working at all.
    I should have listened to my dream a year ago, I could have saved on alot of hair loss. I prayed and asked. I got my answer and ignored it, how foolish! I had such beautiful hair and not it is so thin I can see my scalp. I am glad I saw this site because it promted me to stop the coffee.
    Thanks to the provider of this site. I will post with further progress.

  • Mark

    I think I must have some kind of lower-milder caffeine allergy because when I drink coffee I get real nervous, my nose runs, sneeze a lot, have a sore throat, always have diarrhea, mind is racing. I tend to drink about 2-3 cups per morning. If I quit and just stick to decaffeinated coffee or one soda I’m fine, so I don’t think it is whats inthe coffee, it’s the higher doses of caffeine that make me feel lousy. Thanks, Barney

Last Modified: July 26, 2016


  • 1. Infante, S., Baeza, M. L., Calvo, M., De Barrio, M., Rubio, M., & Herrero, T. (2003). Anaphylaxis due to caffeine. Allergy, 58(7), 681-682. study link
  • 2.Hinrichs, R., Hunzelmann, N., Ritzkowsky, A., Zollner, T. M., Krieg, T., & Scharffetter‐Kochanek, K. (2002). Caffeine hypersensitivity. Allergy, 57(9), 859-860. study link
  • 3. García-Moraleja, A., Font, G., Mañes, J., & Ferrer, E. (2015). Simultaneous determination of mycotoxin in commercial coffee. Food Control, 57, 282-292.