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Fluorescent wee

The past week or so I have noticed my wee was an odd colour. I have been drinking loads thinking I must be dehydrated- now it's fluorescent yellow! I think it might be due to the multivitamin I've been taking, as it happened about the same time I started taking it. Does anyone know, is it just a funny side effect, or is it something I need to take seriously?

Thanks, Rebecca


Super Moderator
Just a guess, but I would suspect it's something in your multi-vitamin. My dad takes all sorts of weird herbal supplements that he doesn't need to be taking and he doesn't even seem to know why he takes them, and I remember a few years ago one of the supplements was something like beeswax or bee pollen. My mom asked him why he is taking it, and all he could come up with was, "Because it makes my pee bright yellow." So see if there's anything to do with bees or bee products in your vitamins! I think it's probably harmless, it didn't seem to affect my dad's actual health in any way.
Hey, better safe than sorry Rebecca! :)

When I started my multivitamin my pee turned more yellow than usual as well. I chalked it up to that because the vitamin is a yellowy color. Now I'm taking azathioprine which turns my pee even more yellow!
I've taken multivitamins for years but only since I started being ill did my wee turn bright yellow. It's only bright yellow first thing in the morning then it goes back to normal. I did also wonder if it was my multivitamins so I stopped taking them for a few days but didnt notice any difference in the colour. I asked my GP about it and he wondered if I was drinking enough as that can make wee brighter but I definitely drink plenty. He said it was nothing to worry about.
My pee always turns bright yellow from multivitamins and also from Imuran as Marissa said. They don't tell you that so I was a little shocked the first time I saw it.
My wee is also neon yellow from my multivitamin, it may be because your body just uses what it needs from it and then rejects the rest of it and it leaves your body through your urine?
Question for the women now (men avert your eyes for a moment, unless you wanna be grossed out): have any of you noticed it making other, erm, bodily fluids bright yellow too?

Ok men you can look now lol.
Hmm...no, I haven't noticed anything like that. Though I would say to watch out for any other changes "down there" - pain, funny smells....yeah I know. Ew...sorry guys! I knoe some medications can make women more susceptible to yeast infections. So, if you're unsure talk to your doc and/or pharmacist! :)
It's not a yeast infection, I have had those before and this is the wrong colour- fluorescent yellow just like my wee. Don't have any other symptoms either, just an odd colour!
Back when I was charting my cycles, the website I used said some discharge can have a yellowish tinge to it that is normal. So, I'd imagine it shouldn't be too strange. Though if it's as neon as your "wee" (that word makes me giggle) I'd ask a doctor about it. Could be a problem with absorbing your supplements? Though that last statement is not based on any facts I'm aware of...just thinking out loud! ;)
I wonder if it glows in the dark? I think it must be due to the b-vitamins as it is the same shade! Hopefully that means my body must be absorbing the vitamin (ie not just pooing it straight out) and chucking it out because it's not needed? And I'm glad my weird body has given you all a giggle.

*Rebecca acts all offended but is really having a chuckle herself*
I do have flourescent pee (sometimes orange too) and I have noticed my "otherly fluids" are more vibrant. LOL

I'm on an ungodly amount of Imuran though (250 mg)


If it is just the color that is different I wouldn't get too worried ... but if there is different odor, stinging/burning, anything abnormal like that, then I'd get it checked....

Imuran is one culprit, as well as many multivits...whether it is vitamins that aren't obsorbed, or (I believe someone else mentioned) the dye in the vitamin....

But, yes, it would be far less worrisome if someone had warned you about it
. :)
The B vitamins are metabolized pretty quickly, but they do get used by your body. When I take my B12 supplement my "wee" turns bright yellow.
Mine gets bright yellow if there is lots of vitamin C. It is water soluable so if there is too much, it just gets peed right out! LOL!!
Yes, I've noticed a definite glow in my knickers! But only since I started the Aza this week. Whew, glad for this thread. Thought my bladder problems were resolving only to be replaced by a yeast infection.
Shine on, ladies :)
I'm on 125mg of Azathioprine and it turns my pee flurescent yellow/green too! haha. Must contain a B12 vitamin.
Just started on Azathioprine, first day, and my wee is bright yellow - panicked and called the pharmacist and she didn't know about it either - is it anything to worry about?
I'm on 125mg of Azathioprine and it turns my pee flurescent yellow/green too! haha. Must contain a B12 vitamin.
Hi, I've just started Azo and my wee has turned bright yellow too - my legs are blotchy as well and the muscles in my leg ache - can't get hold of anyone in IBD to ask what to do - did you have those extra symptoms as well? Confused as to why the Azo leaflet doesn't mention the colour change


Diagnosed July, 2021. Ridiculously new at this!
US (east coast)
My pee is bright yellow since I started taking Sulfasalazine when I was diagnosed with Crohn's one month ago. Just mentioning it in case that is helpful information for anyone.