NEW YORK — For many patients, the inability to pay for drugs is enough of a problem, but what if the drugs they need aren’t available at all?

According to a new report by the Premier Healthcare Alliance, more than 240 drugs were hard to find or entirely unavailable, while more than 400 generic versions of branded drugs were backordered for more than five days. Premier said shortages had more than tripled since 2005, with the frequency and effects rising to critical levels and affecting all segments of health care.

More than three-quarters of the drugs that experienced shortages last year were sterile injectables, particularly those used in emergency situations, according to the report.

According to a Premier survey of 311 pharmacy experts at 228 retail pharmacies, infusion and oncology centers, surgery centers, long-term care centers and hospitals, 89% of respondents experienced shortages that may have caused a medication safety issue or patient-care error, 80% experienced shortages resulting in a delay or cancellation of patient care intervention and 98% experienced shortages that increased costs.