Also indexed as: Cataflam, Voltaren, Voltaren XR
Combination drug: Arthrotec

Diclofenac is used in the treatment of osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis. It is in a class of medications known as non-steroidal anti-inflammatory drugs (NSAIDs).
Summary of
Interactions with Vitamins, Herbs, and Foods
In some cases, an herb or supplement may appear in more than one category, which may seem
contradictory. For clarification, read the full article for details about the summarized
interactions.
|
Calcium Lithium L-tryptophan* |
|
|
Stinging nettle |
|
|
Trikatu Willow* |
|
| Side effect reduction/prevention |
None known |
| Adverse interaction |
None known |
An asterisk (*) next to an item in the summary indicates that the interaction is supported only by weak, fragmentary, and/or contradictory scientific evidence.
Calcium
Diclofenac decreases the amount of calcium lost in the urine,1 which may help
prevent bone loss in postmenopausal women.2
L-tryptophan
Diclofenac causes complex changes to L-tryptophan levels in the blood,3 but the
clinical implications of this are unknown. More research is needed to determine whether
supplementation with L-tryptophan is a good idea for people taking diclofenac.
Lithium
Lithium is a mineral that may be present in some supplements and is also used in large amounts
to treat mood disorders such as manic-depression. Diclofenac may inhibit the excretion of
lithium from the body, resulting in higher blood levels of the mineral.4 Since
minor changes in lithium blood levels can produce unwanted side effects, diclofenac should be
used with caution in people taking lithium supplements.
Stinging
nettle (Urtica dioica)
In a controlled human study, people who took stinging nettle with diclofenac obtained similar
pain relief compared to people taking twice as much diclofenac with no stinging
nettle.5 More research is needed to determine whether people taking diclofenac
might benefit from also taking stinging nettle.
Trikatu
Trikatu, an Ayurvedic herbal preparation that
contains Piper nigrum (black pepper), Piper longum (Indian Long pepper), and
Zingiber officinale (ginger), decreased both blood levels and the medicinal effect of
diclofenac in a study in rabbits.6
Willow
(Salix alba)
Willow bark contains salicin, which is related to
aspirin. Both salicin and aspirin produce anti-inflammatory effects after they have been
converted to salicylic acid in the body. The administration of aspirin to individuals taking
diclofenac results in a significant reduction in blood levels of diclofenac.7
Though there are no studies investigating interactions between willow bark and diclofenac,
people taking the drug should avoid the herb until more information is available.
Food
Taking diclofenac with food may lower the maximum concentration of the drug in the blood and
may delay, but not decrease, absorption.8 NSAIDs such as diclofenac should be taken with a meal
to reduce stomach irritation.
Smoking
Injury to the stomach caused by NSAIDs such as
diclofenac can resolve naturally despite continued administration of the drug. However, the
stomach lining of smokers is less likely to adapt to injury, leading to continued damage from
the drug.9
Alcohol
Chronic consumption of alcohol can aggravate injury to the stomach and duodenal lining caused
by diclofenac.10 To prevent added injury, consumption of alcoholic beverages should
be avoided in individuals taking diclofenac.
1. Sharma S, Vaidyanathan S, Thind SK, et al. The effect of diclofenac sodium on urinary concentration of calcium, uric acid and glycosaminoglycans in traumatic paraplegics. Br J Urol 1991;68:240–2.
2. Bell NH, Hollis BW, Shary JR, et al. Diclofenac sodium inhibits bone resorption in postmenopausal women. Am J Med 1994;96:349–53.
3. Davies NM, Anderson KE. Clinical pharmacokinetics of diclofenac. Therapeutic insights and pitfalls. Clin Pharmacokinet 1997;33:184–213.
4. Davies NM, Anderson KE. Clinical pharmacokinetics of diclofenac. Therapeutic insights and pitfalls. Clin Pharmacokinet 1997;33:184–213.
5. Chrubasik S, Enderlein W, Bauer R, Grabner W. Evidence for antirheumatic effectiveness of Herba Urticae dioicae in acute arthritis: a pilot study. Phytomedicine 1997;4:105–8.
6. Lala LG, D'Mello PM, Naik SR. Pharmacokinetic and pharmacodynamic studies on interaction of Trikatu with diclofenac sodium. J Ethnopharmacol 2004;91:277–80.
7. Davies NM, Anderson KE. Clinical pharmacokinetics of diclofenac. Therapeutic insights and pitfalls. Clin Pharmacokinet 1997;33:184–213.
8. Davies NM, Anderson KE. Clinical pharmacokinetics of diclofenac. Therapeutic insights and pitfalls. Clin Pharmacokinet 1997;33:184–213.
9. Lipscomb GR, Campbell F, Rees WD. The influence of age, gender, Heliobacter pylori and smoking on gastric mucosal adaptation to non-steroidal anti-inflammatory drugs. Aliment Pharmacol Ther 1997;11:907–12.
10. Sifton DW, ed. Physicians Desk Reference. Montvale, NJ: Medical Economics Company, Inc., 2000, 2889–91.