Is diclofenac (Voltaren) more potent than an 800 mg dose of ibuprofen?

Diclofenac (Voltaren) is Stronger Than Ibuprofen 800 mg

Diclofenac demonstrates superior analgesic potency compared to ibuprofen 800 mg, with diclofenac 100 mg achieving a number-needed-to-treat (NNT) of 1.8 versus ibuprofen 800 mg's NNT of approximately 2.7, meaning fewer patients need to be treated with diclofenac to achieve the same pain relief. 1, 2

Comparative Efficacy Data

Direct head-to-head comparisons show diclofenac's superiority:

• Diclofenac 100 mg has an NNT of 1.8 (95% CI 1.5-2.1) for achieving at least 50% pain relief 1, 2
• Ibuprofen 800 mg (closest available data from 600 mg studies) has an NNT of approximately 2.4-2.7 1, 2
• Lower NNT values indicate greater efficacy—diclofenac requires treating fewer patients to achieve meaningful pain relief 1

In a direct comparison trial of osteoarthritis patients, sustained-release ibuprofen 1600 mg daily was rated "good or excellent" by 80% of patients versus only 38% for diclofenac 100 mg daily, though this paradoxically favored ibuprofen despite diclofenac's superior NNT in acute pain studies 3. This discrepancy likely reflects differences between chronic versus acute pain management and tolerability issues.

Critical Safety Considerations

However, diclofenac's greater potency comes with significantly higher cardiovascular and gastrointestinal risks:

• Diclofenac has the worst cardiovascular safety profile among commonly used NSAIDs, with excessively increased risk for stroke, myocardial infarction, and major bleeding 4
• High-dose ibuprofen (2.4 g daily, which includes 800 mg three times daily) may be no safer than intermediate-risk NSAIDs like diclofenac 5
• Ibuprofen has the lowest gastrointestinal risk among non-selective NSAIDs and is considered the safest NSAID option 5
• Diclofenac carries moderate risk for serious upper gastrointestinal events, particularly during the first 6 months of treatment 6

Clinical Decision Algorithm

For most patients requiring NSAID therapy, follow this hierarchy:

1. Start with ibuprofen 1.2 g daily (400 mg three times daily) rather than jumping to 800 mg doses, as this provides adequate efficacy with lower risk 5

2. Reserve diclofenac for patients who fail adequate trials of ibuprofen, recognizing its superior potency but accepting higher cardiovascular and gastrointestinal risks 5

3. Consider topical diclofenac gel as first-line for localized musculoskeletal pain, which provides equivalent pain relief to oral NSAIDs with markedly fewer systemic adverse events 7, 8

4. For patients with cardiovascular risk factors, avoid both high-dose ibuprofen and diclofenac entirely—naproxen may be preferred in these cases 6, 4

Important Caveats

The "strength" comparison is context-dependent:

• In acute postoperative pain, diclofenac 50 mg showed no significant difference compared to ibuprofen 400 mg in direct comparisons 1, 2
• Topical diclofenac was probably less efficacious than oral ibuprofen 400 mg for acute low back pain in emergency department patients, with ibuprofen improving Roland Morris Disability Questionnaire scores by 10.1 points versus 6.4 points for topical diclofenac 9
• The practical clinical difference between these agents may be modest despite statistical differences in NNT values 1

Common prescribing pitfalls to avoid:

• Don't prescribe ibuprofen 800 mg three times daily (2.4 g/day) assuming it's safer than diclofenac—at this dose, ibuprofen's safety advantage disappears 5
• Don't combine multiple NSAIDs, as this increases risk without providing additional benefit 6
• Don't use modified-release preparations, as there's no evidence they're more effective than standard formulations and they cost significantly more 5