deteriorate, lapse, relapse, decline, set someone back, revert, degenerate, worsen, regress, slide back, fall (into decline), take a turn for the worse, suffer a relapse, get ill again, slip back, backslide, get worse, act up, test (positive)

cramp, chafe, scratch, curl up, twitch, sweat, perspire, flush, bleed, pant, black out, burn, narrow, drain, put up with, sting, flag, huff, prickle, linger, gasp, twinge, vomit, barf, cough, itch, ache, curdle, dry out, get the runs, pulsate, sneeze, wheeze, faint, turn over (stomach), come down with, catch (a cold), run (nose), break out in, buckle (at the knees), swoon

seize, hack, choke, contract, shake, quiver, stink, smell, bleed, flail, tremble, shrink, dilate, riddle, leak, flare, pale, discolor, impair, inflame, hurt, putrefy, convulse, vomit, swell, fester, dehydrate, give off (an odor), bloat, malinger, wheeze, pass out, faint, break out in, erupt in (hives), slough off (skin), sink into (a coma), grow (a tumor), metastasize, distend, pus, rattle (lungs), struggle for air, hemorrhage

crack, droop, shrivel, break down, perish, die, age, shrink, bury, wane, weaken, sink, vanish, disappear, decay, disintegrate, deteriorate, succumb, fail, relapse, decline, expire, flag, mutate, wither (away), dissolve, degenerate, waste away, grow old, disfigure, rot, fade away, go limp, lose color, ossify, calcify, give up the ghost, pass away/on, buy the farm, cash in one's chips, kick the bucket, meet one's maker, lay down one's life, bite the big one, croak, atrophy, cremate