In a 2018 study, the U.S. Centers for Disease Control and Prevention reported Fentanyl is now the deadliest drug in America, with over 18,000 overdose deaths in 2016, the most recent year for which statistics are available.

It's the first time the synthetic opioid has been the nation's deadliest drug. For the previous four years (2012 to 2015), heroin topped the list.

But what is Fentanyl?

Fentanyl is a powerful synthetic opioid that is similar to morphine but is 50 to 100 times more potent.

It is a schedule II prescription drug, and it is typically used to treat patients with severe pain or to manage pain after surgery.

It is also sometimes used to treat patients with chronic pain who are physically tolerant to other opioids.

In its prescription form, fentanyl is known by such names as Actiq®, Duragesic®, and Sublimaze®.

Street names for fentanyl or for fentanyl-laced heroin include Apache, China Girl, China White, Dance Fever, Friend, Goodfella, Jackpot, Murder 8, TNT, and Tango and Cash.

Overdoses are soaring 

On average, in each year from 2013 to 2016, the rate of overdose deaths from fentanyl increased by about 113 percent per year. In fact, the CDC says that fentanyl was responsible for 29 percent of all overdose deaths in 2016, up from just 4 percent in 2011.

Overall, more than 63,000 Americans died of drug overdoses in 2016. This is an average of 174 deaths per day.

After fentanyl, heroin, cocaine and methamphetamine were the deadliest drugs in 2016.

According to the National Institute on Drug Abuse, people us fentanyl in many ways. When prescribed by a physician, fentanyl is often administered via injection, transdermal patch, or in lozenges. 

However, the fentanyl and fentanyl cousins associated with recent overdoses are produced in clandestine laboratories. This non-pharmaceutical fentanyl is sold in the following forms: as a powder; spiked on blotter paper; mixed with or substituted for heroin; or as tablets that mimic other, less potent opioids. People can swallow, snort, or inject fentanyl, or they can put blotter paper in their mouths so that fentanyl is absorbed through the mucous membrane.

Like heroin, morphine, and other opioid drugs, fentanyl affects the brain by binding to the body's opioid receptors, which are found in areas of the brain that control pain and emotions.

When opioid drugs bind to these receptors, they can drive up dopamine levels in the brain's reward areas, producing a state of euphoria and relaxation. 

Fentanyl's effects resemble those of heroin and include euphoria, drowsiness, nausea, confusion, constipation, sedation, tolerance, addiction, respiratory depression and arrest, unconsciousness, coma, and death.  

Why is fentanyl dangerous

According to the National Institute on Drug Abuse, the opioid receptors are also found in the areas of the brain that control breathing rate. High doses of opioids, especially potent opioids such as fentanyl, can cause breathing to stop completely, which can lead to death.

The high potency of fentanyl greatly increases risk of overdose, especially if a person who uses drugs is unaware that a powder or pill contains fentanyl. Fentanyl sold on the street can be mixed with heroin or cocaine, which markedly amplifies its potency and potential dangers.

The medication naloxone is an opioid receptor antagonist that reverses opioid overdose and restores normal respiration.Overdoses of fentanyl should be treated immediately with naloxone and may require higher doses to successfully reverse the overdose.

RELATED: 2 police officers exposed to deadly drug during traffic stop in Brentwood

RELATED: 'All of my friends are dead' | Former heroin addict rebuilding her life

RELATED: Missouri Network leads the state in overdose revivals thanks to Naloxone distribution

RELATED: Mother charged after 2-year-old exposed to fentanyl, meth

RELATED: Fentanyl now America's deadliest drug, federal health officials say

From the Archives | Fentanyl to blame for 5 overdoses in 12 hours