I was prescribed the generic for Bactrim for the last ten days for cellulites around a bug bite.........fortunately, i did not have as many of the horrible side effects reported by some, but i realize now that about 7 days into taking it i started to develop a small lump on back of my neck, right below hairline, tender to the touch, now after i have finished day 10, i have two more bumps.....i freaked out, but now after reading some of these posts, it seems it might just be a common side effect with this medication for some.........guess they're just swollen glands.......since I'm done taking already, i guess there's not much to do but to wait for the glands to return to normal!! thanks for the posts, it helps to validate my experience!!