Diclofenac Use in Intractable Radicular Pain

Evidence and Recommendations

The American College of Physicians found insufficient evidence for NSAIDs in radicular low back pain due to inconsistent results, but a 2-week trial of diclofenac is reasonable given established efficacy in other pain conditions and low risk with short-term use in appropriate patients 1
The guideline evidence from the Annals of the Rheumatic Diseases recommends NSAIDs, including diclofenac, at maximum tolerated doses for 2-4 weeks as first-line treatment for spinal inflammatory conditions, with treatment response evaluation at this timeframe 2
Diclofenac dosing for radicular pain should start at 150 mg/day in divided doses, with maintenance of 75-100 mg/day in divided doses, and treatment response should be evaluated at 2-4 weeks 2
The American College of Cardiology is not mentioned in this context, however, the MMWR Recommendations and Reports notes that the cardiovascular risks of diclofenac are dose-dependent and increase with duration of use, particularly beyond the first 6 months, and uncontrolled hypertension is a relative contraindication requiring careful risk-benefit assessment 3
The use of lowest effective dose is recommended, and gastroprotection (PPI or misoprostol) should be considered if any GI risk factors are present 4, 5

Diclofenac carries increased cardiovascular risk compared to other NSAIDs, with a relative risk of 1.63 for vascular events versus placebo, and the risk is highest in the first 6 months but remains present even with short-term use 3
Contraindicated in patients with recent myocardial infarction or coronary artery bypass graft surgery, and relative contraindications requiring careful risk-benefit assessment include heart failure or significant edema, uncontrolled hypertension, chronic kidney disease, and history of peptic ulcer disease without gastroprotection 3

For chronic inflammatory conditions, both diclofenac potassium and sodium formulations are comparable in efficacy to aspirin and indomethacin in rheumatoid arthritis, with no evidence suggesting superiority of one formulation over the other 6, 7, 8
The American College of Cardiology and other guideline societies imply that diclofenac, regardless of salt form, increases the risk of serious cardiovascular thrombotic events, myocardial infarction, and stroke, with a relative risk of 1.63 for vascular events versus placebo 9, 10
Registry data demonstrate a relative risk of 1.54 for recurrent myocardial infarction and 2.40 for mortality with diclofenac use 9, 10

The American Heart Association and other organizations suggest that no particular NSAID, including diclofenac formulations, should be designated as the universally preferred treatment option, and selection should consider patient-specific factors such as past NSAID response, cardiovascular and gastrointestinal risk factors, renal function, and comorbidities 6, 7, 8
Both diclofenac formulations are contraindicated for perioperative pain in the setting of coronary artery bypass graft surgery due to increased cardiovascular risk 9, 10