Today, Moss’s side project is hailed as the next billion-dollar drug. And the once-disinterested pharmaceutical industry is bombarding doctors and the public with information about a serious, if previously unrecognized, condition common among the millions of Americans who take prescription painkillers. They call it “opioid-induced constipation,” or “OIC.”

The story of OIC illuminates the opportunism of pharmaceutical innovators and the consequences of a heavily drug-dependent society. Six in 10 American adults take prescription drugs, creating a vast market for new meds to treat the side effects of the old ones.

Opioid prescriptions alone have skyrocketed from 112 million in 1992 to nearly 249 million in 2015, the latest year for which numbers are available, and America’s dependence on the drugs has reached crisis levels. Millions are addicted to or abusing prescription painkillers such as OxyContin, Vicodin and Percocet. Statistics from the Centers for Disease Control and Prevention show that, from 1999 to 2014, more than 165,000 people died in the United States from prescription-opioid overdoses, which have contributed to a startling increase in early mortality among whites, particularly women — a devastating toll that has hit hardest in small towns and rural areas.

The pharmaceutical industry’s response has been more drugs. The opioid market — now worth nearly $10 billion a year in sales in the United States — has expanded to include a growing universe of medications aimed at treating secondary effects rather than controlling pain.