Uric Acid, Pain & Diclofenac
Gout sufferers must manage their levels of uric acid – pain relief is usually a separate issue.

Some gout patients worry that their pain relief drugs might interfere with their uric acid levels.
Diclofenac (usually sold as Voltaren) is especially feared.
Is this another gout myth? Read on to see why this gout story came about, and why this gout myth is difficult to disprove.
Diclofenac gave vultures visceral gout.
Humans were tested and found to have nowt.
Are blood tests OK? Still there is doubt.
Just listen to GoutPal. He’ll soon sort you out.
Rubbish verse! Interesting uric acid & pain relief story.
Visceral Gout
There have been widespread problems in the Indian subcontinent where huge numbers of vultures died from a disease labeled visceral gout. The vultures contracted this disease as a result of feeding from the corpses of cattle treated with diclofenac. Meteyer et al [1] report:
Diclofenac, a nonsteroidal anti-inflammatory drug (NSAID), has caused sustained population declines in Gyps vultures of Pakistan, India, and Nepal.
Visceral gout describes a form of gout that affects the organs (viscera) of the body [1]:
In addition to the kidney, uric acid crystals were seen most commonly in liver, spleen, lung, and heart, but were also noted in skin, adrenal gland, and parathyroid gland.
In the vultures studied, the visceral gout is secondary to kidney problems caused by diclofenac poisoning. Visceral gout, as opposed to articular gout (gout in the joints), appears not to affect humans.
However, this still leaves the question: can diclofenac raise uric acid levels?
Diclofenac & Uric Acid
Diclofenac is a commonly prescribed anti-inflammatory treatment for gout pain, but there is not much research into it’s effects on uric acid in humans.
I’ve found two studies that indicate that diclofenac has no effect on uric acid:
- Jelić-Ivanović et al[2] studied the effects of 5 anti-inflammatory drugs on uric acid and 11 other blood components. They found that diclofenac had no effect on uric acid – it’s only effect being to raise urea, which increased significantly in the first 2 weeks of the trial, but returned to normal during the next 10 weeks. The only drug in this study that affected uric acid was ibuprofen, which lowered uric acid. Though only 8 ibuprofen taking subjects were measured, the average uric acid level fell from 5.35 to 3.86 mg/dL.
- Al-Arfaj et al[3] studied the effects of 5 different drugs (unfortunately not including ibuprofen). Interestingly, they were investigating the combined effects of these drugs with fasting. The fasting experience showed increased uric acid after 10 days of fasting, falling back to slightly below the starting point after 15 days. This pattern repeated across all drug groups and the control. Diclofenac showed a very slight uric acid increase, deemed to be insignificant.
The conclusion from these studies is that diclofenac has little or no effect on uric acid in humans. However, the first of these 2 studies brings into question some tests results.
Diclofenac & Blood Tests
There are several ways of testing uric acid levels, but their reliability depends on accurate test procedures. If the test for uric acid is affected by traces of drugs, then the results are unreliable.
Prior to reporting that diclofenac had no effect on uric acid, Jelić-Ivanović et al had published previous investigations into the affects of drug on laboratory tests[4]. They report that:
Glucose, uric acid and iron values were altered in the presence of diclofenac.
They also note that uric acid tests were affected by ibuprofen and acetylsalicylic acid (aspirin). Though they adjusted their own results, other studies may not be strictly accurate.
Does this mean it is pointless to rely on uric acid tests if the patient is taking diclofenac, or other pain relieving drugs?
Diclofenac: GoutPal View
My view is that uric acid testing is vital to gout control. Any slight variations to test results should not affect normal gout management, though they should be factored into any scientific research.
The correct use of diclofenac is a short term pain relief medication. It’s patient information sheet, as for all similar NSAIDs, warns of risks associated with long-term use.
If gout is managed correctly, the control of uric acid means that pain relief will only ever be required as a short term measure – if at all.
Next Uric Acid Pain Steps
You have seen how diclofenac can be useful as a short term pain reliever. Like all NSAIDs, it is not without risk.
Gout treatment for pain relief should always be viewed as a short term measure until uric acid is lowered to suitable levels.
You should establish a clear plan for lowering uric acid with your doctor, and discuss if diclofenac is suitable in your circumstances, or if a better pain relief treatment is available.
Uric Acid Pain References
- Meteyer CU, Rideout BA, Gilbert M, Shivaprasad HL, Oaks JL. Pathology and proposed pathophysiology of diclofenac poisoning in free-living and experimentally exposed oriental white-backed vultures (Gyps bengalensis). J. Wildl. Dis. 2005;41(4):707-716. Visceral Gout Vulture Diclofenac Poisoning Full Text (PDF)
- Jelić-Ivanović Z, Spasić S, Majkić-Singh N, Todorović P. Effects of some anti-inflammatory drugs on 12 blood constituents: protocol for the study of in vivo effects of drugs. Clin. Chem. 1985;31(7):1141-1143. – Uric Acid & Pain Relief: Blood Effects Abstract (PDF) – Uric Acid & Pain Relief: Blood Effects Full Text (PDF)
- Al-Arfaj HF, Alballa SR, Alhaider AA, et al. Effect of short-term use of different non-steroidal anti-inflammatory drugs on renal function during fasting in ramadan. Saudi J Kidney Dis Transpl. 1995;6(1):9-14. – Uric Acid & Pain Relief: Kidney Function Effects Full Text (PDF)
- Jelić-Ivanović Z, Majkić-Singh N, Spasić S, Todorović P, Zivanov-Stakić D. Interference by analgesic and antirheumatic drugs in 25 common laboratory assays. J. Clin. Chem. Clin. Biochem. 1985;23(5):287-292.
~GoutPal
Tags: Clin. Chem., diclofenac, ibuprofen, J. Wildl. Dis., Saudi J Kidney Dis Transpl, uric acid pain
