FILE - Adderall XR capsules are displayed on Feb. 24, 2023. Drug shortages are growing in the United States, and experts see no clear path to resolving them. The U.S. Food and Drug Administration announced last fall a shortage of the attention deficit/hyperactivity disorder treatment Adderall due to a manufacturing problem. (AP Photo/Jenny Kane, File)
CNN  — 

Amid an ongoing shortage of prescription stimulants in the US, federal agencies are calling on drugmakers to boost manufacturing and on health care providers to closely monitor prescribing practices.

The US Food and Drug Administration announced a shortage of Adderall, a common treatment for attention-deficit/hyperactivity disorder (ADHD), in October. The stimulant shortage was initially expected to last a few months but persists nearly a year later.

“The FDA and DEA do not manufacture drugs and cannot require a pharmaceutical company to make a drug, make more of a drug, or change the distribution of a drug,” FDA Commissioner Dr. Robert Califf and Drug Enforcement Administration leader Anne Milgram wrote in a joint letter Tuesday. “That said, we are working closely with numerous manufacturers, agencies, and others in the supply chain to understand, prevent, and reduce the impact of these shortages.”

A surge in prescriptions for stimulant drugs in recent years, coupled with the residual effects of manufacturing delays that one key drugmaker experienced last fall, are among the “many factors” contributing to the shortage, they wrote.

Stimulants are controlled substances, and the DEA does set limits on the amount that can be produced. But an internal analysis suggests that manufacturers fell 30% short of the full quota in 2022, leaving about 1 billion potential doses on the table. And there’s a “similar trend” this year, according to the letter.

The DEA says it is “committed to reviewing and improving” the quota process but asks that manufacturers relinquish any quota they can’t meet so it can be redistributed.

The letter also highlights “widespread misuse” of prescription stimulant drugs and calls for “accelerate(d) efforts to support appropriate diagnosis and treatment of ADHD,” including more robust clinical guidelines for diagnosing ADHD in adults and alternative treatment options.

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report published this year by the US Centers for Disease Control and Prevention highlighted a surge in demand for prescription stimulants during the Covid-19 pandemic, especially among adults.

The FDA tracks the manufacturers that have reported shortages of prescription stimulants on its website. The listed reasons for the shortages include “demand increase,” “shortage of active ingredient” or no reason at all. Estimated recovery dates range from this summer to December.

“The lack of availability of certain medications in recent months has been understandably frustrating for patients and their families,” Califf and Milgram wrote in their letter.

“We will consider additional actions to prevent non-medical use and identify efforts to better understand and strengthen the supply chain. We also hope that we can all work together to assure that those who need stimulant medications can get them based on the best clinical knowledge about when they are effective, and avoid them when there is no indication for their use.”