NPR had a hit with this headline recently: “World's Most Popular Painkiller Raises Heart Attack Risk.” Sensational, and not wrong. Diclofenac in particular is an extremely popular drug — we’re talking oral here — and it is associated with serious cardiovascular risks: “There is increasing regulatory concern about diclofenac. … Diclofenac has no advantage in terms of gastrointestinal safety and it has a clear cardiovascular disadvantage” (McGettigan et al). But the difference between oral and topical is extremely important. Topical is not the same thing as swallowing at all. Volatren Gel (or Emulgel) is still a useful product. It has a proven benefit and much lower risks than oral. Scott Gavura wrote about this for ScienceBasedMedicine.org today:
The main advantage of topical NSAIDs is the reduced exposure of the rest of the body to the product, which reduces the side effect profile. Given the toxicity of NSAIDs is related in part to the dose, it follows that topical treatments should have a better toxicity profile. Consequently, the cardiovascular risks of topical diclofenac … should be negligible with the topical forms.
I’ve updated my article on this topic: