A composition having proanthocyanidin compounds having an average degree of polymerization of at least about 6. A method of administering to an immunosuppressed patient or a patient diagnosed with sepsis or septic shock a composition having a proanthocyanidin. A method of administering to a patient diagnosed with a gram negative bacterial infection a composition having proanthocyanidin compounds having an average degree of polymerization of at least about 6.