There are no real symptoms from liver flukes that you would notice casually. (Except at the hyperinfection stage, when you will have all sorts of symptoms but very diffuse ones: fatigue, lethargy, brain fog, water-swollen abdomen from liver damage (a pseudo-beer-belly, basically), elevated bilirubin levels, etc.)
I had all of the above symptoms when mine got to the hyperinfection stage, and I had no idea it was liver flukes (I had no idea what a liver fluke was). Until one obese fasciola hepatica or gigantica got stuck in a gallbladder duct, giving me a severe gallbladder attack that required a 911 call, an ambulance ride to the emergency room, and three days in the hospital while the puzzled emergency-gallbladder-surgery team that had been assembled to remove my gallbladder looked in vain for any sign of Gallstones
in my gallbladder.
are the usual cause in the West of gallbladder attack, i.e., biliary duct obstruction. I have no gallstones; in my case, it was presumably a big fat fluke.)
Anyway, I was very lucky to have an honest surgeon in charge of the team who did not whack out my gallbladder (the malpractice-defensively-safe thing for her to do), but instead told me she had no idea what had caused my gallbladder attack but since ultrasounds and CT scan had shown no signs of gallstones, and I had passed whatever was jammed in my bile duct, and 3 days of IV doxycillin had cured the resulting inflammation/infection, she was releasing me with my gallbladder intact.
And a medical mystery that it took me about ten minutes to half-solve on Google, which told me there is of course another cause of thickened gallbladder wall, inflamed/infected gallbladder, and bile-duct obstruction besides gallstones -- liver flukes.
The other half of the mystery was solved when three days later I passed a bolus of dead flukes. Something they did in the hospital killed them -- the scans or the doxy, presumably, as that's all that could have. Since some were fasciola, that is, big honkers, I sorta saw them in my stool just looking at it (after blood and mucus on the tp alerted me I might want to take a look in the bowl). I went to the CDC site, found their Parasite Image Library, matched my critters to the pics of fasciola and c.sinensis, and had my answer -- I had liver flukes. I Googled the treatment protocol, which brought me here and also to various public-health sites, which have variants. I used the fluke treatment protocol here while waiting 2 weeks for an appointment with an ID doc, because I wanted the things out as soon as possible, given their tendency to land me in the ER & then the hospital.
Which was a good idea. The protocol here works, whereas the Infectious Disease doc, with his lucrative travel medicine practice, prestigious hospital affiliations, and MD from Columbia, told me the whole specimen I brought in looked like a piece of zucchini (my telling him I don't eat zucchini made no impact) and diagnosed me officially with constipation and unofficially but obviously with delusional parasitosis. I begged for a stool test (not yet knowing about the notorious unreliability of stool tests), which request he very reluctantly granted, and which of course came back negative anyway, even though I had put quite a few of the most obvious dead flukes and a lot of ova in both containers, along with some stool.
Lung flukes are also asymptomatic until they get really bad. Or, you scare them "awake" by taking prazi for your liver flukes. Either way it starts, the symptom is that you begin to have to compulsively spit, because the back of your throat tickles. And you spit up really thick, bubbly, mucus-y spit that's tinged pale brown (that's blood, I later read). The latter happened to me when I was doing the prazi for my c. sinenses, & went on for two days and then stopped. I think the prazi got most of them. And I think I have finished off the rest now -- I rested a while and then ordered triclabenzadole for the fasciola from Dr. Chieu and that seemed to do for most of the rest; after the tricla course, there was only the faintest tinge of pale brown when I spat after brushing my teeth. A final course of prazi a bit later has cleared that up, and my spit is clear again.
Now for the tapeworms, and then the hookworms. (Sigh.)