Critical shortages of the ADHD drug Adderall and the antibiotic amoxicillin have left families reeling as the medicines their loved ones need become harder to find.

It's become a familiar struggle as supply and demand have fallen out of sync during the pandemic, with manufacturers of various consumer goods struggling to keep up.

Drugmakers have offered little insight into the reasons for the shortages, other than to blame surging demand. In the case of amoxicillin, demand has become particularly acute amid a so-called tripledemic of Covid, respiratory syncytial virus, or RSV, and the flu that are converging this season.

But according to experts, drug companies face few repercussions for not disclosing key information about the production of these medications, such as which third parties manufacture them, or where and how they are produced.

As a result, U.S. consumers remain at the mercy of drug companies when it comes to learning the cause of the shortages or how and when they might be resolved.

"It’s very opaque," said Erin Fox, a senior pharmacy director at University of Utah Health based in Salt Lake City. "Medications are one of the things we purchase and spend large amounts of money on, but we have no idea where they're made, or even which company is making them."

The Food and Drug Administration's website currently lists amoxicillin and Adderall, also known as mixed amphetamine salts, as being in short supply. For amoxicillin, the reason for the shortages by drugmakers either state "demand increase for drug" or "other." In the case of Adderall, one company's description says the drug is "backordered" and another says there will be "supply constraints through January 2023." Neither of these companies elaborated.

"It's all voluntary," Fox said. "They don't have to tell us."

NBC News reached out to two of the drugmakers responsible for producing both Adderall and amoxicillin. Israel-based Teva, one of the largest generic drugmakers in the world, did not respond to multiple requests for comment.

In August, it blamed shrinking Adderall supplies on a temporary labor shortage and said there would be intermittent delays. In October, the FDA said Teva was continuing to experience "ongoing intermittent manufacturing delays," and that there was not yet sufficient supply from other manufacturers to meet U.S. market demand.

Michelle Bauman, a representative of the Swiss American generic medications company Sandoz, a unit of Novartis, said it is facing "a significant demand uptake resulting in a supply situation for some of our Sandoz antibiotic medicines," such as amoxicillin and its alternatives. She highlighted investments that she said Sandoz is making to increase output capacity, in part by hiring additional personnel at its manufacturing facility in Kundl, Austria.

She said Sandoz now projects its output to more than double this year compared with 2021, but did not specify exactly when it expects key shortages to be resolved.

FDA announces amoxicillin shortage

Nov. 16, 202203:58

"The combination in rapid succession of the pandemic impact and consequent demand swings, manufacturing capacity constraints, scarcity of raw materials and the current energy crisis means we currently face a uniquely difficult situation," Bauman said. She did not address the Adderall shortage.

As the Covid pandemic bore down, the National Academies of Sciences, Engineering and Medicine convened a team of researchers, including Fox, to study the security of America’s medical product supply chain. The group concluded this spring that a lack of transparency and deference to confidentiality "conflicts with public health needs and puts the public’s health at risk."

Drug manufacturing is a commercial business, and companies by and large compete on the open market. But when makers of generics compete mainly on price and aren't forced to consider reliability, the marketplace can break down when demand surges or supply chains are disrupted, according to Ozlem Ergun, a distinguished professor of mechanical and industrial engineering at Northeastern University, who served with Fox on the committee.

"It is not like a regular marketplace," she said of the pharmaceutical industry. "The shortages are a symptom. It shows the marketplace doesn’t really work."

In 2020, Congress passed the Mitigating Emergency Drug Shortages Act, which aimed to address some of these issues. One requirement was that drug companies provide critical manufacturing data to the FDA. But the agency is not required to disclose that information to the public — and Fox said the FDA has so far proved limited in its ability to enforce the act beyond naming companies that are not complying.

"There are no real teeth for noncompliance — no fees, etc, just a naughty list," she said in an email.

Another legislative effort is underway to address the issue. Sens. Susan Collins, R-Maine, and Gary Peters, D-Mich., have sponsored the Registration of Certain Foreign Establishments Act, which would require foreign manufacturers that distribute medical products in the U.S. to register with the FDA and identify all other facilities where manufacturing may have occurred.