Loss of Drug Potency
Some hospital pharmacists have been in touch with us recently to report potency issues with certain medications prepared in advance in 3 mL or 5 mL BD syringes. One of the medications is fentaNYL citrate injection diluted to 10 mcg per mL for pediatric use, which was prepared in a hospital pharmacy. One hospital sent 3 syringes of diluted fentaNYL 10 mcg/mL to an outside laboratory for testing. At 48 hours, the potency had declined to 67% on average, and by day 6, the potency was at 55%. Another hospital tested syringes of fentaNYL 5 mcg/mL in 3 mL syringes and found a range of potencies between 10% and 70%. Retesting at two other laboratories showed similar results. A third hospital reported inadequate patient analgesia, also with diluted fentaNYL
We spoke with a BD representative, who confirmed that an issue exists. The issue may be related to black plunger rod stoppers from a secondary supplier that affect “pH sensitive” medications such as fentaNYL citrate, methadone hydrochloride, and possibly a few others. BD continues to investigate the matter and is planning to send a letter shortly to pharmacy directors to provide more details. Potency problems have not been identified with BD 1 mL, 10 mL, and larger syringe sizes, and no problems have been reported with other manufacturers’ syringes.
According to BD, the loss of potency is also time dependent. At 24 hours, fentaNYL remains between 90 to100% potent, but by 48 hours, some deterioration may already be underway, as noted above. Patient safety could be compromised if subpotent opioid doses cause a dose elevation that is followed by administration of a fully potent opioid at the higher dose via a syringe that does not have this issue.
Until further information is available from BD and the problem is resolved, hospitals using BD 3 mL and 5 mL syringes should prepare medication syringes as close to the time of administration as possible. One of the hospitals that identified the problem is providing a 1 mL dose of fentaNYL 10 mcg per mL in a 2 mL vial for now.