Updated

Shortages of drugs for attention deficit hyperactivity disorder (ADHD) had patients and their families on a hunt Tuesday for pharmacies with drugs in stock.

Some families are paying more for pricey alternatives, or cutting back usage to stretch supplies.

"It's a huge inconvenience," says Erin Fox, manager of the drug-information service at the University of Utah Hospital & Clinics. "Parents and patients are running around and calling pharmacies to see who has their product."

Recent shortages of Adderall XR and its generic equivalents, also known as amphetamine mixed salts, as well as of methylphenidate, a generic version of the brand-name drug Ritalin, have been reported in Pennsylvania, Maryland, Minnesota, Washington state and elsewhere.

The shortages affect drugs that generated a combined 24.2 million prescriptions in 2010, according to data provided by IMS Health.

Matt Cabrey, spokesman for Shire, the maker of Adderall and generic versions, said increased diagnoses of ADHD can make it difficult to forecast ingredient needs. But the current shortage, Cabrey said, is due to a delay last year at the US Drug Enforcement Administration (DEA) in releasing extra supplies of the drug's active ingredients.

Because of the potential for abuse, the DEA regulates the active ingredients of some ADHD drugs as controlled substances. DEA spokesman Lawrence Payne said the agency has approved enough supply to allow for uninterrupted distribution of the drugs and it is up to manufacturers to allocate the ingredients among their various products.

ADHD causes children and adults to have difficulty focusing, controlling their actions and remaining still or quiet. ADHD drugs generally act as a stimulant to alleviate symptoms but can be habit-forming and associated with side effects such as increased heart rate and loss of appetite.

Rebecca Brown, diagnosed with ADHD as an adult nearly a decade ago, said the shortages have created "chaos" in her life. A 51-year-old retail worker, Brown was recently taking generic versions of Adderall. But earlier this year, she was unable to refill her prescription at pharmacies near her Media, Pa., home.

She cut her dosage to stretch her supply, then went off the drug completely for about a week -- which she said left her feeling "foggy" and unmotivated. Eventually, she switched to a branded version of Adderall.

Click here to read more on this story from the Wall Street Journal.