U.S. Senator Pat Toomey (R-PA), this week criticized the limitations of a new Medicare and Medicaid opioid prescription-monitoring program set to start next year.

Toomey said just 44,000 patients will fall under the umbrella of a new Centers for Medicare & Medicaid Services initiative, or “less than 3 percent of the people that the Centers for Disease Control believes are at risk based on the quantities that they are receiving.”

His comments came during a special hearing in his district Tuesday reported on by the local PBS affiliate.

Mary Denigan-Macauley, acting director for healthcare at the U.S. Government Accountability Office, testified that the program was designed to detect beneficiaries who may be filling prescriptions from multiple doctors or pharmacies, rather than those who are given high doses from a single prescriber. The approach would essentially ignore long-term care residents, who typically receive their prescriptions by an affiliated pharmacy and may not have family caregivers to raise questions about appropriate dosing or alternative treatments.

“There are still many, many people getting very large quantities of prescription opioids through federal government programs, and their consumption of these opioids is not being properly monitored,” said Toomey, quoted by WHYY.

Toomey said patients on high doses are at higher risk for addiction. But Medicare has no existing or publicly announced plan to ensure they’re not being prescribed too many pills.

“We made a recommendation in our 2017 report that (CMS) decouple that and to be able to track what you’re asking them to track,” said Denigan-Macauley, whose full testimony is available here.

The Centers for Disease Control and Prevention issued guidelines in 2016 recommending providers use caution when prescribing opioids at any dose, reassess evidence of individual benefits and risks when increasing dosages and avoid or carefully justify dosage at 90 mg.That same year, 1.6 million Medicare beneficiaries were receiving prescriptions at the 90mg threshold, Toomey said.

One out of three people enrolled in Medicare’s prescription drug benefit plans received an opioid in 2016, according to the U.S. Department of Health and Human Services, making the federal government the nation’s largest buyer of them.