Well, we live in a hot zone--lower Hudson--with lots of deer, lots of deer ticks, and (from testing), a high percentage of ticks that carry Lyme and related co-infections.
There's some good info in this thread, but also a few posters who think it is prudent to avoid the antibiotics. My personal opinion--if you have been bitten, take the Doxy immediately--and then take a probiotic to keep your digestive tract in order. I can't stress this enough--the consequences of leaving the Lyme spirochete in your body untreated are far worse than the disruption of the antibiotic. And the doctors in the 'hot zones' know this, and know that the first "test" will come back negative, and by the time the (inadequate) test comes back positive, the little bastids could have gone anywhere.
As my doc says, Lyme is the new syphilis--and it can infect internal organs, joints, brain (one friend has permanent memory problems from an untreated infection).
So don't be "manly" about it--if you have been bitten by a deer tick, and you live where Lyme is prevalent--get the Doxy and take it! (Dog or brown ticks do not carry the infection). Second--if you start to feel crappy and live where ticks are prevalent, insist that your doctors do a Lyme test as part of your blood panels--you may have to argue the point, but tell them that you spend a lot of time outside.)
I'm at four infections and counting--first was classic (bullseye rash) and it laid me low for months, and took over a year for me to recover to a functional state (and the first test came back negative!), and took me a lot longer to really feel like myself.
Second was another full-blow co-infection (Babesiosis) that attacks your white blood cells--no visible signs, I just kept getting weaker and feeling worse until my wife piled me into the car and took me to Emergency (Never saw the tick, never had a rash). They tested, it came back positive for the Lyme coinfection and they started me on blood transfusions immediately. (Good news--Doxy kills the co-infections as well).
Third was no rash/bullseye, just slow decline with flu-like symptoms. I preemptively started on Doxy that time, and it seemed like it did not get a real foothold.
Fourth was this summer--I was outside a lot painting the house, was bitten, never saw the tick, no rash, no real catastrophic symptoms--I was just getting slower and feeling more tired (which I put down to the hard work of painting the house)--until I finally went to the doctor, and almost as an afterthought asked if they would run the Lyme test--and it came back positive/active infection yet again. Twenty one days of Doxy, and I am still feeling the after-effects with arthritis-like symptoms. Already checked in with the Doc, and it is in reversal, and I'll do a followup checkup at the 6 month stage.
Don't mess with Lyme, it will destroy your health if you let it.
On this page (Loudon County VA) is a great brochure that they issued--on the RH side, click on the image with the picture of the tick) and it will open a PDF that is the best single document that tells you what you need to know:
https://www.loudoun.gov/index.aspx?NID=1273