I started Doxycycline Hyclate several days ago (100 mg 2x daily) ...

I started Doxycycline Hyclate several days ago (100 mg 2x daily) as part of 3 week regimen to treat Lyme Disease. I have had some stomach upset, a generally reduced appetite, and cottonmouth... but by far and large the biggest effect has been this overwhelming exhaustion. Went to bad at 9:30 last night and woke up at 9:00 am this morning but could not drag myself outta bed until almost noon. Its now the middle of the afternoon and I feel like a complete zombie. Spacy and unmotivated, my head might as well be made of wood and can't pull it together to even take a shower yet. I am a real outdoors guy and keep up a busy routine of work and exercise. Another 2 and a half weeks of this is gonna drive me nuts. I guess it is better than having Lyme, but does it get any easier?