There are not many differences between diclofenac sodium and diclofenac potassium, since they are rooted from diclofenac.
some of the differences between them are:
diclofenac potassium is more soluble in water than diclofenac sodium with that, it relieves the pain of the patient in a faster time. making it more useful for acute pain.
diclofenac sodium tablets (Voltaren) are delayed or extended release while diclofenac potassium tablets ( Cataflam) are immediate release.
Delayed- and extended-release forms of diclofenac sodium were initially developed with the goal of improving the safety profile of diclofenac and providing convenient, once-daily dosing for the treatment of patients with chronic pain.
New drug products consisting of diclofenac potassium salt were associated with faster absorption and rapid onset of pain relief.
So diclofenac sodium tablets are more suitable for patients with chronic pain, while diclofenac potassium is suitable for acute pain.