Why is there an opioid crisis? What can be done to stop it?

Drug overdoses are the leading cause of death for Americans under 50, and deaths are rising faster than ever, primarily because of opioids.
Overdoses killed more people last year than guns or car accidents, and are doing so at a pace faster than the H.I.V. epidemic at its peak. In 2015, roughly 2 percent of deaths — one in 50 — in the United States were drug-related.

Florida's lawsuit suggests the main cause is profits for big pharma:
http://www.tampabay.com/opinion/editorials/Editorial-Bondi-holds-drug-industry-accountable-for-Florida-opioid-crisis_168349934

From the National Institute on Drug Abuse:
Every day, more than 115 people in the United States die after overdosing on opioids. The misuse of and addiction to opioids—including prescription pain relievers, heroin, and synthetic opioids such as fentanyl—is a serious national crisis that affects public health as well as social and economic welfare. The Centers for Disease Control and Prevention estimates that the total "economic burden" of prescription opioid misuse alone in the United States is $78.5 billion a year, including the costs of healthcare, lost productivity, addiction treatment, and criminal justice involvement.

How did this happen?
In the late 1990s, pharmaceutical companies reassured the medical community that patients would not become addicted to prescription opioid pain relievers, and healthcare providers began to prescribe them at greater rates. This subsequently led to widespread diversion and misuse of these medications before it became clear that these medications could indeed be highly addictive. Opioid overdose rates began to increase. In 2015, more than 33,000 Americans died as a result of an opioid overdose, including prescription opioids, heroin, and illicitly manufactured fentanyl, a powerful synthetic opioid. That same year, an estimated 2 million people in the United States suffered from substance use disorders related to prescription opioid pain relievers, and 591,000 suffered from a heroin use disorder (not mutually exclusive).

What do we know about the opioid crisis?
• Roughly 21 to 29 percent of patients prescribed opioids for chronic
pain misuse them.
• Between 8 and 12 percent develop an opioid use disorder.
• An estimated 4 to 6 percent who misuse prescription opioids
transition to heroin.
• About 80 percent of people who use heroin first misused
prescription opioids.
• Opioid overdoses increased 30 percent from July 2016 through
September 2017 in 52 areas in 45 states.
• The Midwestern region saw opioid overdoses increase 70 percent
from July 2016 through September 2017.
• Opioid overdoses in large cities increase by 54 percent in 16 states.

What can be about it?
In response to the opioid crisis, the U.S. Department of Health and Human Services (HHS) is focusing its efforts on five major priorities:

1. Improving access to treatment and recovery services
2. Promoting use of overdose-reversing drugs
3. Strengthening our understanding of the epidemic through better
   public health surveillance
4. Providing support for cutting-edge research on pain and addiction
5. Advancing better practices for pain management