I wonder what the long term effects are of using diclofenac patches (e.g. one patch applied daily and kept for 24 hours positioned on the lateral epicondyle of the humerus). By long term I mean several months or more.
diclofenac by itself has a weak COX-2 selectivity and inhibition of COX-2 can cause or exacerbate hypertension and increase the likelihood of thrombotic events
what is the most important information I should know about medicines called NSAIDs? new or worse high blood pressure; heart failure; liver problems including liver failure; kidney problems including kidney failure; low red blood cells (anemia); life-threatening skin reactions; life-threatening allergic reactions. fda side effects
fda info regarding more specifically to your question it may represent an increased factor of hepatotoxicity
Physicians should measure transaminases at baseline and periodically in patients receiving long-term therapy with diclofenac, because severe hepatotoxicity may develop without a prodrome of distinguishing symptoms. [...] However, severe hepatic reactions can occur at any time during treatment with diclofenac.
Long-term administration of NSAIDs has resulted in renal papillary necrosis and other renal injury.
and finally the GI tract
NSAIDs, including diclofenac, cause serious gastrointestinal (GI) adverse events including inflammation, bleeding, ulceration, and perforation of the esophagus, stomach, small intestine, or large intestine, which can be fatal.
in summary we could sum up all of this with
Because serious GI bleeding, hepatotoxicity, and renal injury can occur without warning symptoms or signs, consider monitoring patients on long-term NSAID treatment