"We are very aware that while the risk of infection from insulin pen re-use is extremely small, cross-contamination from an insulin pen is possible, " Finan said.

WSJ: 2nd NY hospital warns of insulin pen infection

"Interviews with nursing staff indicated that the practice of using one patient's insulin pen for other patients may have occurred on some patients, " said Timothy Finan, president and chief executive of Upper Allegheny Health System, the parent company of the Olean hospital.

WSJ: 2nd NY hospital warns of insulin pen infection

"Regardless, to the extent there may be a chance, however remote, that any patient was provided insulin from an insulin pen other than their own, Olean General Hospital has decided to be proactive and aggressive with respect to notification of our patients, " the release said.

WSJ: 2nd NY hospital warns of insulin pen infection

Today, in lieu of injecting with a needle or pen, some patients carry an insulin pump loaded with the shorter-acting insulin.

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Meanwhile, as Pfizer had to conduct long safety studies to deal with the lung capacity issue, insulin shots got less painful as companies like Becton, Dickinson developed less painful needles and drug firms started to market insulin in easy-to-use pre-packaged "pen" devices.

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