The United States is currently in the middle of a heroin and opiate epidemic. According to the Centers for Disease Control and Prevention (CDC), the rate of heroin-related overdose deaths nearly quadrupled between 2002 and 2013. Heroin claimed the lives of over 8,200 Americans in 2013.

We have seen heroin epidemics in the U.S. before, but this latest one is a little different in that a large percentage of addicts have made the transition from prescribed opioids to heroin. Many are making the move because heroin is both easier and cheaper to obtain than prescription pain relievers like OxyContin and Percocet.

Here are a few interesting facts about heroin that you may or may not be aware of.

Heroin and products containing it were once sold over-the-counter.

Heroin was first synthesized in 1874 from morphine, but it was not introduced for medical use until 1898, when The Bayer Company of Germany (today known as just Bayer) released it as a safer alternative to morphine for pain relief. The name heroin was coined from the German word meaning “heroic, strong” because of the effects it was having on patients.

At the time, heroin was marketed as a non-addictive painkiller in products such as cough syrup and sold over-the-counter. Some physicians were even recommending it as a sleep aid.

Within a few years, instead of being less addictive than morphine, heroin was found to actually be far more addictive, as much as two to three times as much. In 1924, the United States Congress banned its manufacture, sale, and import.

Heroin comes in three different colors.

Heroin is sold as a white or brown powder or sometimes as “black tar heroin”, a sticky black substance.

Heroin from Columbia, Pakistan, and Afghanistan is usually brown. The white powder version typically comes from Southeast Asia and is more pure. It is becoming increasingly rare in the U.S. Often times the white powder version has fillers and/or contaminants added to it such as sugars or powdered milk.

Black tar heroin is only produced in Mexico. When the drug is cold, its appearance is similar to a Tootsie Roll, but more solid. When it is warmed, it becomes more sticky like tar.

Black tar is the lowest grade and least pure version. It often has other forms of opioid drugs added into it.

Severe itching is a common side effect of heroin use.

An often unexpected side effect of heroin use is severe itchiness. Opiates can cause histamines to be released in your body. Histamines are the compounds a body produces during an allergic reaction. They irritate the skin, often times causing itchiness.

Many users think the itchiness is a sign of lower purity in their heroin, but the opposite is actually true. The more pure the heroin is, the more likely it is to cause itchiness.

Heroin has many nicknames.

Heroin goes by H, horse, thunder, smack, and junk on the streets. Sometimes it is also referred to by its appearance, such as brown sugar or black tar.