agonize

verb4

1. •
   To writhe with agony; to suffer violent anguish.

   • His Touch, if tremblingly alive all o’er, / To smart, and agonize at ev’ry pore? — 1733
2. •
   (literary) To struggle; to wrestle; to strive desperately, whether mentally or physically.
3. •
   To cause agony or anguish in someone.
4. •
   To act as an agonist upon; to combine with a receptor on a cell to produce a physiological reaction.