The present invention provides methods for treating a disorder, and methods for inhibiting a stress-activated protein kinase (SAPK) in a cell in an individual, the methods generally involving administering to an individual in need thereof an effective amount of pirfenidone or a pirfenidone analog; comparing a post-treatment SAPK activity level in a biological sample from the individual with a pre-treatment SAPK activity level; and adjusting the dose of the pirfenidone or pirfenidone analog based on the results of the comparison step. The present invention provides methods for treating a disorder, and methods for inhibiting a SAPK in a cell in an individual, the methods generally involving administering to an individual in need thereof an effective amount of pirfenidone or a pirfenidone analog; comparing a second post-treatment SAPK activity level in a biological sample from the individual with a first post-treatment SAPK activity level; and adjusting the dose of the pirfenidone or pirfenidone analog based on the results of the comparison step.