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
  • hombre

    that has got to suck

  • Hellzenvy

    I’m wondering how much of that is caffeine allergies and not a reaction to another ingredient. Take for instance my Co work and I both now after months and months of drinking have Adverse reactions to Monster Khaos or Lost 50 same drink different can. My co-work breaks out in a rash and i get Pain in the chest but other energy drinks don’t seem to have any adverse effects.

  • The Crowing

    number one makes me laugh. i used to have skin problems (most notably eczema) but seemingly since i started to really pump in the caffeine i haven’t seen a trace of it. could just be coincidental timing, but idk..

  • Eeeekkk

    Oh thank god I don’t have this….
    On the other hand, I am allergic to beer, *expletives*
    Still I guess mushy head symptom is better than itchy anus every day of the week

  • Helen

    I don’t think i have a caffeine allergy – I think it is a trigger for something else, but that something else has yet to be diagnosed even after an MRI, an ultrasound, and a colonoscopy. Any caffiene from any source gives me extreme abdominal pain, with enough quantity i will be screaming and moaning for several minutes, and sometimes pass out. this may or may not involve spastic crapping. I am not exaggerating. I have had to avoid caffeine as though it would kill me, because i have had one of these episodes strike me while driving and it almost did kill me.

    And all any doctor can tell me is “it sounds like a reaction to stress” or it might be IBS, but IBS wouldn’t just go away completely if you didn’t have one trigger, but as long as i never have caffeine again, i’m fine.

    at this point, i’m just crossing my fingers to never have this reaction to chocolate.

  • Helen A. Handbasket

    @Helen – doesn’t chocolate have some caffeine in it?

    Good Luck!

  • Melonie

    Ugh… I have a caffeine allergy and it’s no fun. I didn’t discover it until I was a teenager (I’m 23 now). Ever since, I’ve avoided it like the plague, but it’s unfortunate that there really is no cure for it, and not much treatment to speak of.

    I’m completely fine with avoiding caffeine, but having some sort of treatment would be nice. Every once in a blue moon I might drink a glass of pepsi in hopes of being “cured”, but I quickly realize it’s not the case, and always regret it. Yet I still push my limits from time to time, which is absolute idiocy on my part.

    However, that’s all stopping now, because just yesterday I decided to drink a can of soda and the symptoms are worse than ever. What worries me is no neurological it really is. The physical symptoms are bad enough, but when your brain starts getting affected, that’s when things get scary. After doing more research, I’ve learned that, depending on how severe your allergy is, having a “relapse” could be potentially life threatening. After what I’ve had to endure in these two little days from something so simple as having a can of soda, I believe it.

    Awareness would be nice. When I went to the doctor about this seven years ago, they assumed it was a heart problem. Although, after rigorous testing, it was discovered that my heart was completely healthy and I was in great shape physically, not having a single problem in any area. My doctor told me he didn’t know what was wrong and left it at that, and it was later that I discovered I had this allergy.

    I just wish there was more information about it and help, because it’s not fun to live with. It’s fine when I avoid caffeine (which I do), but every once in a while it will rear its ugly head in, and it’s very dangerous.

  • RB

    Drinking coffee/caffiene etc since I was 21. Always on the heavy side and it moved into monster proportions. My crutch through 2 university degrees / demanding jobs/ stress/ a middling feeling about life/ not especially happy to mild depression. Some 30 years later I’m getting raised bumps and sores on my arms/very itchy that I scratch and break open. Took me a few of those years to self-diagnose myself as having hives due to caffiene allergy. Do something long enough and in medicinal quantities and you will become allergic to it. This was hard to self diagnose because information about it on the internet was not very prevalent until recently. I’ll have to quit but right now shooting for moderation at 50-100mg a day and the use of loratadine/antihistamine…all related to hives. Quitting would be best though.

  • Ashii

    Well I have the heart racing & Jitters, and maybe anxiety, but i’m not allergic to caffiene.

  • RB

    Hives, caffiene allergy also known as caffeine urticaria (Hives, welts, etc deriving from caffeinated beverages). Some people develop this from alcohol/tobacco also..usually after years of abuse.

  • Dave

    This is why your skin goes crazy.

    Common pesticides and herbicides in non organic coffee.

    Aldrin, Dieldrin,Chlordande, Heptachlor, Endosulfan,Chlorpyrifos, Diazinon, Disulfotoon, Methyl parathione, Triadimeton, Cypermethrin.


  • shelly

    I have had sever hives for 3 years. I have recently stopped drinking coffee and am doing better. I also have had vision problems, heart racing, and facial numbness. I thought I was having mimi strokes, but I believe it is the caffine.

  • zoe

    Im thinking I definitely have a caffeine allergy,big red patches (painful) appear some hours after I have coffee, tea, chocolates and even coca cola for close to half a year. it comes wih difficuly breathing the more I take and pain in the chest. it sucks but I might have to drink hot ho milk in the morning!

  • TJ

    I drink a few cups of coffee in the AM. For several months somewhere around dinner time to late evening, I develop itchy hives in mostly the hot spot areas, like arm pits, around the waist where the pant waist is, etc.. I recently decided to stop drinking coffee for a week and found that I had very minimal to no hives each day. Then, I decided to start drinking coffee again to see if there would show a difference, and I developed some hives, but not as much as before. Maybe, its because most of it was out of my system. I’m thinking if I continue to drink some every day as usual, it may get worse again. I’m not sure how long it takes to get out of your system, but I’m thinking to quit for at least 2 weeks this time to see if it completely goes away.

  • GS

    RB, your experience and symptomsmimics mine precisely – even down to your age consumption rate. After being wracked with horrible, undiagnosable rash for the last four years that has sent me to a series of demertologists to no effect, just a few weeks ago I finally figured out it was the coffee.

  • John

    “Also, there is a fine line between caffeine sensitivity and allergy, but overall we’re dealing with the body not being able to correctly process the caffeine molecule so whether you want to call that sensitivity or allergy it’s up to you.”

    ‘Allergy’ has a fairly precise definition and is a very-well understood medical phenomenon dealing with immune reaction. To lump all these symptoms under the heading of ‘allergy’ and blithely claim that it is just “up to you” what you want to call it is mere promulgation of ignorance.

  • Brett

    I thought I had a reaction to coffee at first, after working near a coffee company where I use to drink it all day working at a bench related electronics job.

    Symtoms were –

    1)Very bad nasal blockage like a sinus infection.
    2)later progressing to loose stool growly noisy bowel.
    and rashes on the skin.
    3)This then got a bit worse with very itchy anus and butt crack area itch with sweating.
    4)also seem to perspire a lot more than normal and have a hot feverish feeling all over. pain in RHS under rib (irritared bowel)
    5)Generally this gives a not well feeing which tend to give concentration and stamina issues.
    6)vision also is out of focus up close and improves when the caffine is dropped. The loose stool also goes away.

    Gave up tea and coffee – problem gone except when I give in and have a coffee or tea. Coke / Pepsi or cola drinks also have same effect but not as bad as coffee.

    Hope this helps someone out there diagnose caffene intollerance.



  • Wilma

    Well, that just sucks. Not only am I allergic to alcohol, now I read this. With 17 of the 20 symptoms,(not #16,18 or 20) it is a fair guess that I am also allergic to caffeine. I have been going to doctors for the past few years and with no real answers. Now, I am scheduled for a CT scan and back to the oncology clinic. One of the websites that I read mentioned high white blood cell count (which seems to be the norm for me) but no one can figure out why. Another website mentioned misdiagnosed mental disorders because some of the symptoms are the same. Doctors are pretty quick to give out antidepressants and antianxiety medications anyway. Another website mentioned how caffeine contributes to obesity. About seven years ago (at age 30!)I was prescribed Atenolol and Hydrochlorothiazide for heart palpitations. At the time I was about 15 pounds over weight (according to Marine Corps standards) Over the years since, I have grown sick of being sick, but no one could tell me why or what caused all of aches and pains. So all that I have to do is give up coffee, coke, chocolate, and excedrin…and my health problems will go away…and I wont have to take Prednisone,Atarax, or Zantac for unexplained hives and itchy skin…and my face and ears wont feel like someone lit them on fire??? That’s amazing!
    Wilma Flintstone

  • Anna

    I have horrible rashes all over my body….started getting them slowly a few minutes after i had that cup of coffee….and now its my second day and the rashes are getting even thinking about going to the doctor but is there anything recommended for the time being.

  • Adrienne

    It wasn’t until about two years ago that I realized I had a caffeine allergy. I drank coffee for years (and loved it – still do, just won’t touch it now) and then switched to tea only to find it caused reactions as well.

    With coffee, I get heart palpitations. Once it was so bad I actually was sent to the emergency room. The tests all showed I have a very strong, healthy heart. The doctor had no answer for it, but since I usually feel a skip and abnormal rhythm when I drink coffee (just never that severe until that day) I’m sure it was the caffeine.

    Also with coffee I develop acne all over my face – generally on my forehead. Without it, my skin stays clear. Within a day of coffee, however, I have a massive breakout.

    Tea, unfortunately, gives me extreme ear aches and itchy ears. I mean extreme ear aches – mostly in the left ear, oddly enough. I went to a doctor about it, but they only gave me antibiotics which, by the way, does not instill within me much confidence in going to a doctor and having them at least ATTEMPT to diagnose me properly.

    I have yet to drop from having chocolate in my diet. I know it’s perpetuating the minor, less severe versions of the symptoms I’ve listed above (minus heart palpitations – I don’t get those unless I have coffee, thank gosh). I’m just going to have to buckle down and kick chocolate to the curb. Alas.

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.