Disclosed are novel anti-inflammatory pharmaceutical compositions and related methods that exhibit potent and selective inhibition of the cycloooxygenase-2 (COX-2) enzyme. The formulation can comprise a hops extract that exhibits COX-2 selectivity as defined by dividing the IC50 COX-2/IC50COX-1 concentrations that are determined by testing with the William Harvey Whole Blood Assay (WHMA), and can fall within the range of 0.011 to 0.2. Such compositions may also optionally contain high levels of alpha acids and low levels of beta acids, some flavonoid compounds, and virtually no essential oils. Such compositions are useful for treating conditions that manifest as inflammatory pain, or are impacted by the COX-2 enzyme. The recited compositions are particularly beneficial for treating osteoarthritis and rheumatoid arthritis, and can be used for chronic pain with reduced gastric side-effects.