The gel came close to the best pills, and raised no side-effect risk
In a network of 192 trials, topical diclofenac at 70 to 81 mg a day had at least a 92% chance of clearing the smallest pain drop patients notice, with no raised adverse-event risk.
What the study found
Topical diclofenac matched the best pills for knee and hip pain
In a network of 192 trials, topical diclofenac at 70 to 81 mg a day had at least a 92% probability of clearing the smallest pain reduction patients notice, close to the best oral options. No topical preparation showed a raised risk of any adverse event, against 29.8% of oral ones.
The caveat · About half improved on plain gel
About half the people using the carrier gel alone also counted as a success, roughly twice the usual response to a dummy pill, so part of what people feel comes from the vehicle and the act of rubbing rather than from the drug. Every trial in the topical review was in osteoarthritis, almost all of it knee osteoarthritis. Up to 6,000 participants' worth of completed but unpublished data was unavailable to the reviewers. Trials with fewer than 100 patients per group were excluded from the network.