Elevated calcium and vitamin D blood levels are commonly found in people with sarcoidosis. In one individual with sarcoidosis, taking flubiprofen lowered elevated blood calcium levels, but did not alter the concentration of vitamin D.¹ One controlled study showed that flurbiprofen reduced blood levels of vitamin D in people with frequent calcium Reference kidney stones.² Further research is needed to determine whether flurbiprofen reduces blood calcium and vitamin D levels in healthy people.

Elevated calcium and vitamin D blood levels are commonly found in people with sarcoidosis. In one individual with sarcoidosis, taking flubiprofen lowered elevated blood calcium levels, but did not alter the concentration of vitamin D.³ One controlled study showed that flurbiprofen reduced blood levels of vitamin D in people with frequent calcium Reference kidney stones.⁴ Further research is needed to determine whether flurbiprofen reduces blood calcium and vitamin D levels in healthy people.

Nonsteroidal anti-inflammatory drugs commonly cause damage to stomach and intestinal tissue. Though the mechanism by which NSAIDs cause this side effect is unknown, some researchers believe that free-radical damage is involved. A test tube study showed that flurbiprofen increases free-radical activity in stomach cells, which is blocked by the antioxidant N-acetyl cysteine.⁵ Additional research is needed to determine whether people taking flurbiprofen together with N-acetyl cysteine might experience fewer gastrointestinal side effects.

White willow bark (Salix alba) contains salicin, which is related to Reference aspirin. Both salicin and aspirin produce anti-inflammatory effects after they have been converted to salicylic acid in the body. The administration of salicylates like aspirin to individuals taking oral NSAIDs may result in reduced blood levels of NSAIDs.⁶ Though no studies have investigated interactions between white willow bark and NSAIDs, people taking NSAIDs should avoid the herb until more information is available.