Thinking & Feeling

“The world is a tragedy to those who feel, but a comedy to those who think.” Horace Walpole

Saturday, 15 September 2012

Shiitake Dermatitis Syndrome

So the past week has been fun - NOT! But thankfully after a week of the most extreme and severe itching and discomfort and feeling weird and out of sorts the Shiitake Poisoning seems to be going away now! YAY!

It really affected me badly. I couldn't run, or do my usual gym classes or even sleep. I would wake up clawing at myself and going out of my mind from itchiness. It was horrid. Eventually the blisters were even in my ears and on my eye lids too. They were EVERYWHERE. I looked and felt like a leper and had to explain to people that I was not contagious with some dreaded disease. And because it was a TOXIC and not allergic reaction the usual treatments like antihistamines and cortizone cream didn't help. I had to just ride it out.

Today is the first day I feel well and normal again, and damn it feels great!

Wanna see what they look like?

Here is some more info on the condition:
Blistering red welts. A rash that spreads from the back of the hands to the neck, legs, back and abdomen. Is it poison oak? No — it's shiitake dermatitis, a bizarre reaction to eating raw or under-cooked shiitake mushrooms.
Have you ever heard of this?
More common in Asia, shiitake dermatitis is thought to be a reaction to a component of the mushroom called lentinan, which breaks down when heated. Not everyone is susceptible; in one study, only nine patients out of about 500 developed a rash after contact with lentinan. Interestingly, because the response is not triggered by the immune system, it is considered a toxic reaction rather than an allergy.
The New York Times Magazine recently ran a story about a woman diagnosed with shiitake dermatitis, alerting us to this strange condition. Although fully cooked shiitakes can be safely eaten even by those who react to lentinan, one rash was enough for her: “I’m never going to touch another shiitake."
• Check it out: Diagnosis: A Red Scare - New York Times Magazine


  1. Hi Jane, I got it in Hamburg around 2006 or 2007. Don't know who the specialist doc knew, but he asked me straight away, if i had eaten shiitake, which I had. I'm not so sure they were undercooked though. I tend to avoid Chinese fare as well. Best Regards, Bjarke

  2. Thanks for the comment Bjarke. Interesting that your doctor knew about it. The Pharmacisit I consulted with assumed it was from the Sushi I had eaten...

  3. Hi Jane,
    I just wanted to say thanks for your blog and photos. I had this reaction twice before I finally turned my suspicions on shiitakes. Your blog helped me to confirm :-)
    I live in England and have seen several healthcare professionals about this rash. All of which just assumed "an allergic" reaction and offered various creams and pills, none of which worked.
    I don't have any other allergies - I am so happy to be able to say I don't have any allergies again.
    Many thanks again for your blog,
    Tim Winspear

  4. Hi Jane,
    I just wanted to say thank you for your blog and photos :-)
    I've suffered this reaction twice now, but it wasn't until the morning after I ate a few leftover raw shiitakes that my suspicions turned sharply on the shiitakes. With thanks to your blog I was able to confirm :-)
    The UK doctors and nurses I saw were clueless and just prescribed various allergy pills and creams.
    I'm so happy to be able to say I am allergy free again :-)
    You've got to know where your towel is at!
    All the best,

    Tim Winspear

    1. Pleasure Tim. It was a google search and some blog posts that helped me to track down what it was and self-diagnose,so I am happy to be able to help other people... I have been through it twice now, and now that I have conclusive evidence and proof I am very careful about avoiding them (even cooked) now, as it is not fun and not something I plan to go through again, if I can help it! :)

    2. Hello Jane,
      My husband and I ate raw shiitake mushrooms last thursday. Saturday he had red streaks on his arm and head. It has spread all over now. Should he go see a doctor or will it go away? We live in the United States but fear no one will know what it is. Thanks for your time, Sarah

    3. Hello Jane,
      My husband and I ate raw shiitake mushrooms last Thursday. Saturday, he had red streaks on his head and arm. They have spread now all over. What can he take for this? He doesn't want to see the doctor. He thinks they will just misdiagnose it. Thanks for your help.

    4. Hello Jane,
      My husband and I ate raw shiitake mushrooms last thursday. Saturday he had red streaks on his arm and head. It has spread all over now. Should he go see a doctor or will it go away? We live in the United States but fear no one will know what it is. Thanks for your time, Sarah

    5. Hi Sarah.
      It has happned to me twice now. I inadvertently ate Shiitakes again when I went to Borneo a couple of years ago. They were in a cooked stew, but were whole and were obviously not cooked right through. I didn't realise they were not regular button mushrooms... so in the plane on the way back. ongo it hit me again. The second time was not as bad as I did eat as much and they weren;t entirely raw.

      It does go away. It takes a good week, or up to 2 weeks, though. Also if you get hot and sweaty (ie exercise) it makes it MUCH more red and itchy and clistery.

      I was given a cortizone cream for the forst round which helped to reliee the symptoms. SO you can ask for something like that. Basically whatever the doctor would prescribe for excema.

      It's not serious or life threatening (unless you can't breathe or something) so you can let it run it's course. Once the wets are all out it doesn;t continue to get worse and will steadyily go away. It's not an allergic reaction though, it's a toxic reaction.

      Just avoid Shiitakes going forward.

      Good luck to him. It's not very pleasant!

  5. Hi Jane, this has really helped me. Your pics look exactly like my torso this last week after two consecutive lunches involving shiitake. I'm in New Zealand and none of the doctors have heard of it... they think it's scabies even though I haven't been in any situations at all where I could have caught it, and my husband is 100% fine. I've also been feeling quite ill, nauseous and out of sorts, but that's starting to recede now. Anyway onward and upward! Cheers, Caren

    1. Hi Caren.
      I am glad it was able to help! That's why I posted it...

      I hadn't looked at that post or thought about SDS for a long time. Argh, it brought back horrid memories! I still remember how agonizing it was. The good news is it does dissipate, and I haven't had it again since. After 2 bouts of it though, I am a lot more careful about all mushrooms and avoid anything that has shiitakes in it altogether now, whether cooked or not.

      A general soothing ointment definitely helps to treat the itchy symptoms, but otherwise I think you do pretty much have to just ride it out.

    2. Thanks Jane. It's pretty unnerving because two different GPs both thought it was scabies. And I'm no expert. By the same token none of them know anything about shiitake dermatitis - I know more than they do. I'm riding it out, if it doesn't resolve then I'll do the scabies treatment. Did you have generalised itching? And feel tired and nauseous?

    3. To be honest I don't remember much besides the itching. The itching was intense and relentless. And yes I think I itched everywhere. But on re-reading my posts I see I did say I felt tired/sleepy, lethargic and 'out of sorts' too. You should feel progressively better. I think it takes a good week, and up to 2 to totally go away. I think it's pretty rare and unheard of in the western world, so not many doctors would have heard of it at all. All the best and I hope it doesn't happen again!

  6. Thanks! Me too!