Two and a half weeks after Pharmacia stopped the sale of the Cox-2 inhibitor parecoxib (DYNASTAT), the company is telling professionals about "important new safety information" (1). Life-threatening hypersensitivity disorders have been documented in association with valdecoxib (USA: BEXTRA), the active metabolite of parecoxib, such as anaphylaxis, angioedema, erythema multiforme, exfoliative dermatitis, STEVENS JOHNSON syndrome and toxic epidermal necrolysis (LYELL syndrome).
Parecoxib and valdecoxib are sulphonamide derivatives. Some of the adverse reactions affect patients with known sulphonamide allergy. Sulphonamide allergy is therefore now listed as a contraindication (1).
The process has revealed deficiencies in competency among manufacturers and the European licensing authorities with regard to preventive consumer protection:
What we found fault with upon introduction to the market is now being corrected: "Sulphonamide hypersensitivity reactions can be expected. This is not mentioned in the data sheet" (a-t 2002; 33: 62-3).
No official information has been provided regarding the incidence and severity of the observed harmful effects. According to information, which pharmaceutical representatives have passed on as "confidential", there have been reports of the following: STEVENS JOHNSON syndrome (7), exudative erythema multiforme majus (5) and LYELL syndrome (1).
While the company has temporarily stopped factory sales, it has not withdrawn the product from the market. However, when sales are stopped because of risk, there is a legal requirement for recall (AMG § 69, para. 1 clause 2, no. 4), to prevent patients from being put at risk by products whose package leaflet does not reflect current knowledge.
We regard "postoperative pain relief", the officially authorised indication for parecoxib, as a contraindication: nonsteroidal anti-inflammatory agents like parecoxib impair the autoregulation of renal perfusion. In situations of stress, such as in the first few days after an operation, this can result in acute renal failure.
CONCLUSION: in view of the danger of severe hypersensitivity reactions and the paradox listing of "treatment of postoperative pain" as an indication we once again caution against the use of the Cox-2 inhibitor parecoxib (DYNASTAT).