It’s a non-steroidal anti-inflammatory drug for dogs and it’s been linked to too many deaths. This has been well documented but Dogster wants to make sure everyone is aware. You can do a Google search for Caprofen / Rimadyl. More than 1 in a 1000 dogs suffer negative side effects from the drug, some of which are very slight. Of the .18% that suffer side effects, sadly 13% died or were put to sleep. Here is a FDA report with all the details: http://www.fda.gov/cvm/CVM_Updates/rimadyl2.html.
Rimadyl continues to be recommend and any vet should know this situation better then all most anyone, but we’d recommend double checking on any prescribed usage just in case.
[Correction: I originally made a big mistake by saying 13% of dogs that used the medicine died. What I should have said was 13% of those that suffered negative effects (which is .18%) died. This is still way too many in my book, but far far far fewer than what I implied at first. Also note the FDA changed their URLs, the above URL now points to the new posting place of the data.]