If Lyme is caught very early in the infection (and many of us never knew when we were bitten),
doxycycline can work, but only against
Lyme: perhaps half of all 'Lyme' ticks also carry other diseases unrelated to Lyme which do NOT respond to doxycycline at all. These infections include bartonella, babesiosis, ehrlichiosis and others, and are often referred to as a group as 'co-infections'.