The present disclosure relates, in general, to compositions comprising phosphatidylcholine and phosphatidylcholine derivatives, e.g., DLPC (1, 2-dilauroyl-sn-glycero-3- phosphocholine) or DPPC, for the treatment of fibrosis, including liver fibrosis and associated conditions such as fatty liver disease, non-alcoholic steatohepatitis (NASH) and cirrhosis, or lung fibrosis and conditions associated with lung fibrosis.