Self-assembling peptides or self-assembling peptidomimetics ("SAP") can treat inflammation or inflammatory diseases, or reduce one or more symptoms of diseases and disorders associated with undesirable inflammation. Topical and injectable compositions of SAP for local administration to a site of inflammation for reduction or prevention of symptoms of inflammatory diseases and disorders are described. The compositions include one or more SAP in an amount and concentration effective to reduce or prevent one or more symptoms of undesirable inflammation. The SAP can assemble prior to or after the composition is administered. The SAP form a structure within or at the surface of the body that prevents and/or reduces symptoms associated with inflammation and other dysregulated immune processes. The peptides can assemble upon contact with bodily fluids (e.g., synovial fluid), or can be contacted with ionic solutions to initiate assembly.
