Neither, it is a central nervous system depressant. Problems with blood clots might occur if the user is injecting the drug since this is usually done with less than sanitary equipment and the veins...
Celebrex is a COX-2 inhibitor grouped into drugs called NSAID's (nonsteroidal anti-inflammatory drugs). Some NSAID's thin the blood, so individuals taking blood thinners or anticoagulants should...