I was misdiagnosed for a full year, and undiagnosed for some years before that.
My main symptoms were:
1. nausea and vomiting
2. dizziness/dizzy spells
3. weight loss
1. some abdominal pain, not much
2. dark circles under my eyes
3. extremely tired all the time
It turned out I had Giardia.
The aspects that confused the docs:
95% of folks with giardia have diarreah. I didn't. Guess someone has to be that last 5%!
I was having trouble digesting. They did all kinds of tests, including having me eat some radioactive oatmeal (I kid you not) and watching it go down, through some kind of scanning machine.
That was the "last" test my GI specialist did, because he couldn't think of any other tests to run at that point. He had never tested for parasites because of the lack of diarreah.
His conclusion? Combined with not finding the reason for my symptoms and the fact that I had dizziness as one of my symptoms (heard this before?) he concluded that I was psychosomatic.
Short version of the story from there, is that I was trying to self-diagnose, having spent about a year taking medical tests and consistently getting worse. My husband came in and found a medical book open to parasites. He read it. He said he wanted me to get tested for parasites.
I argued, saying that I didn't have the symptom pattern. He insisted, saying that we had tested for everything else, and what did we have to lose?
I tested positive for Giardia. Took 10 days of Flagyl (NASTY medicine...makes you a bit insane) and cleared up the giardia.
Then it took me six months for my GI tract to get back to even remotely normal, and another year for it to get all the way back.
Here, at this site, it says nothing about dizziness with giardia. But when I told my friend I had finally found out I had giardia, she came back with a search in about 8 minutes, finding someone else who was finally diagnosed who had written on some medical board who also had dizziness and no diarreah.
Within one month of my cure, my friend started having symptoms similar to mine (dizziness, nausea, bloating, digestion problems) and with diarreah. She asked her doc if it could be giardia.
He said "no" because she hadn't been out in the woods or anything, where she could catch it.
She insisted on getting the test, since she had been with me through my misery. She tested positive.
Also not on this website in how you catch giardia: poopy diapers, particularly through day care. She had two diapered kids in day care at that time. She had them tested, even though there were no symptoms. One had giardia.