according to the link Arcoxia should be monitored in patients when first administered or the dose is changed (if taking Warfarin)
www.medsafe.govt.nz/Profs/Datasheet/a/Arcoxiatab.htm - 31k -
was the link i found - there are tons of others with varying degrees of jargon by googling with 'Arcoxia warfarin contra indications'
best luck