Giardia is one of those things that makes you poop your brains out! Keep in mind that this is on a spectrum ranging from maybe 2 or 3 bouts of diarrhea a day to not being able to leave the toilet for any appreciable length of time. The person infected also has foul smelling gas, sulfurous burps, sometimes loses weight, and sometimes has floating greasy poop. It spreads via the oral-fecal route and is commonly acquired through drinking out of lakes or streams. Drinking standing water near a beaver dam is particularly risky because it’s standing water the beavers are pooping in, hence the term “beaver fever.”
As I learned recently (oops!), it can also be transmitted through sex or other intimate contact that involves the butt. Sometimes that oral-fecal route gets to be pretty direct!
If you don’t do anything, your symptoms may well resolve in 4-6 weeks but you’ll still be able to pass it on to others, even while you feel fine. I am not finding good data yet on how long a person can give this gift that keeps on giving… Also, sometimes the symptoms just don’t go away on their own- so there’s that, too.
It’s a decent idea to go ahead and treat it both because that’s the community-minded thing to do and because during that 4-6 weeks that you have giardia the intestine is getting all fucked up and the more fucked up it gets, the longer it takes to really get back to normal afterwards. There are a couple of antibiotic choices you’d have to go to a clinic to get, one of them is cheaper and you can’t drink alcohol on it (for real, you’d get crazy sick) and one is more expensive but you can drink alcohol while you’re on it.
A small medical study showed success treating giardia with an herbal drug called “‘Pippali Rasayana” 1gram by mouth, three times a day for 15 days, so that might be something to try instead of antibiotics.
Some people find they have a temporarily lower tolerance to milk (lactose) right after they’ve had giardia- so you may want to avoid large amounts of dairy while you have giardia and for maybe a couple weeks after successful treatment just in case.
Avoid it by treating questionable water, washing your hands, and being careful about who’s butt your mouth goes near!