(for veterinary information only)

BRAND NAME: FELDENE

BACKGROUND

The need for non-steroidal anti-inflammatory drugs (NSAIDS) in human medicine is profound. There are a plethora of products both over the counter for routine aches and pains (aspirin, ibuprofen, ketoprofen etc.) and stronger prescription products (celecoxib, rofecoxib etc.) Piroxicam is one of the prescription products for human use.

Arthritis pain is an important cause of loss of mobility in the dog as it is in humans.  Before there were NSAIDs available for dogs, human medications were used. Aspirin was the staple medication but when aspirin was not effective there were few alternatives.  Piroxicam was sometimes used for such cases.

NSAIDS exert their anti-inflammatory effects by inhibiting an enzyme called "cycloxygenase." The problem, in a very simplified summary, was that there were two types of cycloxygenase (called "COX-1" and "COX-2"). The one responsible for creating most unpleasant inflammatory is COX-2 but the NSAIDs were inhibiting both.  This created the potential for serious NSAID side effects: development of kidney insufficiency, stomach/intestinal ulceration,  and blood clotting disruption through platelet cell deactivation (all because of its inhibition of COX-1).

Currently, COX-2 selective NSAIDs are available and medications such as piroxicam have become less popular.  Piroxicam might have completely faded into obsolescence were it not for possible anti-tumor effects found especially useful in the treatment of bladder cancers. Questions persist as to how piroxicam is able to suppress such tumors and currently it is believed that this effect relates to immune system related effects rather than direct action against the tumor cells.

HOW THIS MEDICATION IS USED

The Transitional Cell Carcinoma of the urinary bladder is the most common target of this medication though it is also used against mammary adenocarcinoma, squamous cell carcinoma, and transmissible verereal tumors.

Piroxicam is also used in some cases of Feline Lower Urinary Tract Disease which have been refractory to other therapies.  Cats seem to be especially sensitive to NSAID side effects so this would be considered a "last resort" treatment.

INTERACTIONS WITH OTHER DRUGS

Piroxicam should not be used in combination with other COX-1 inhibiting drugs such as steroids or other NSAIDs.

The use of piroxicam reduces the necessary dose of the chemotherapeutic medication Methotrexate. 

SIDE EFFECTS

As with other NSAIDs, side effects include GI ulceration, prolonged bleeding, and potential for kidney insufficiency. This medication should not be used in patients where such conditions are pre-existing.

Humans taking this medication occasionally report ringing of the ears and headaches. We, obviously, do not have a good way to assess whether animal patients also experience these side effects.

CONCERNS AND CAUTIONS

Piroxicam should be stored so as to protect it from light exposure.

Vomiting or diarrhea may indicate that GI ulceration has occurred. If either of these symptoms are noted, discontinue the medication and contact your veterinarian promptly.

This medication is usually given once a day or every other day.

Some blood test monitoring may be recommended with long term use.