The therapeutic recommended dosages were 12.5, 25, and 50 mg with an approximate bioavailability of 93%. Rofecoxib crossed the placenta and blood–brain barrier, and took 1–3 hours to reach peak plasma concentration with an effective half-life (based on steady-state levels) around 17 hours. The metabolic products are cis-dihydro and trans-dihydro derivatives of rofecoxib which are primarily excreted through urine.
