As you may have guessed, celecoxib (Celebrex) is the answer to the question: “If blocking COX-1 is so much of a problem, why does it have to happen?” Of course, the real answer is that it is extremely complicated to formulate a drug that is so selective.
Celecoxib was developed as a drug for arthritis. It is a selective COX-2 inhibitor, so it annihilates inflammation, kills pain, brings down fevers, and causes vasoconstriction (which also helps quell the inflammation), all without touching the homeostatic, protective side of things. So, great, right?
Well, celecoxib does its job well, but a little too well in some respects. Although it doesn’t mess with protective COX-1, it does cause an awful amount of vasoconstriction. It’s possible that the fact that non-selective NSAIDs mess with platelet aggregation actually makes this a little less of a problem with them.
Celecoxib carries a big risk for heart attack and stroke, primarily due to vasoconstriction. Since the blood isn’t thinned at all by this drug (a purposefully-avoided side effect!), the constriction of the blood vessels can be very problematic. Also, the people to whom this drug is marketed (those with arthritis) tend to be older and thus at greater risk for these complications anyway!
Ah, well it was a good try. Celecoxib is an effective and selective drug, but we have to be very watchful of its dangerous effects.