A dangerous mix of prescription-strength codeine and sugary soda that has been a popular drug in the southern rap community for decades -- and has caused numerous deaths -- could spread to a younger generation through social media, according to a professor of behavioral sciences at the University of Texas.
After a health scare landed multi-platinum rapper Lil' Wayne in a Los Angeles hospital last week and prompted rumors of his death, a spotlight has been placed on the dangerous recreational narcotic drink Wayne and other rappers have sung about.
The concoction has only just started to be referred to as "sizzurp." It is more commonly called "sippin' syrup," "oil," "purple stuff," "drank," "lean" and in one form of the mixture, "mud."
When people on the street want to sell you some, they might ask, "Do you need an oil change?"
"Sippin syrup" is promethazine/codeine syrup mixed with high-caffeine or fruit-flavored soda or alcohol. Fruit-flavored candy is often added to increase its sweetness. According to one expert who has studied its influence in Houston, where the drink originated, "sippin syrup" is "extremely addictive" and remains "very common."
"It is still considered to be the champagne and caviar of drugs here in Houston," said Ronald Peters, an associate professor of behavioral sciences at the University of Texas Health Science Center. Peters has been conducting studies on "sippin' syrup" for 13 years.
Peters said "drank" was first popularized in the 1970s, with Robitussin and codeine. People "would cut it with beer back then," he said, and it was particularly popular in the Third Ward, in Houston's south side.
The next Houston generation grew up with the emergence of hip-hop in the 1990s, and the message of people drinking "sippin syrup" spread like wildfire.
Hip-hop producer Robert Davis, better known by his stage name DJ Screw, created an innovative form of hip-hop music called "Screw music." While others in the southern hip-hop scene were using fast beats, Screw was the first to "slow it down," Peters said, and in his music, "he simply told the world what was going on in Houston."
In one 1996 song by Screw called "Sippin Codeine," his rap opens with the line, "I sip codeine/It makes a south side playa lean."
From Houston, which Peters called the "mecca of hip-hop music in the '90s," "sippin syrup" spread to other states as it gained popularity across southern hip-hop circles. From there, its popularity spread to another new generation that has embraced YouTube, Twitter and other social media.
In the Houston area, people would often drink "sippin syrup" out of Styrofoam cups -- so much so that local law enforcement has picked up people who were spotted holding such a cup while walking down the street.
The Styrofoam cup became a sort of symbol for the drink in the Houston area. Wayne and other rappers have been seen holding large Styrofoam cups in pictures and videos.
But the concoction of promethazine, which is an anti-histamine, codeine, which has opulent properties, mixed with alcohol or caffeine -- the combination of three substances in one -- can be dangerous.
Drinking enough of "sippin syrup" can produce a high very similar to that of heroin, and it can be as addictive.
Peters said not a lot of studies had been done about "sippin syrup." But in one study he conducted in 2003 with around 100 high school-age kids, who said they were current "sippin syrup" users, Peters said many of them reported feeling high after the first time trying it.
"Some of them had issues with insomnia, where they couldn't sleep without it, made them irritable," Peters said. "They reported having 'syrup comas,' you know, that was the extreme."
Codeine is a sedative that is also used in prescription cough syrup as a pain reliever and to make people sleepy. It can depress the respiratory rate, heart rate and blood pressure.
It was an overdose of codeine, mixed with drugs, that caused the death of DJ Screw. Big Moe, another Houston native and a protégé of DJ Screw, named albums "City of Syrup" and "Purple World" for the "drank" and died in 2007 of a heart attack at the age of 33. Many speculated that "sippin syrup" led to his death.
Rapper Pimp C, whose real name was Chad Lamont Butler, also died in 2007. According to the Los Angeles County Coroner's Office, Butler died of respiratory depression caused by the promethazine/codeine in his system, coupled with a pre-existing sleep apnea condition. Sleep apnea causes breathing to pause or go shallow during sleep.
It is still unclear exactly what happened to Lil' Wayne, with some people saying that he suffered from seizures while others have indicated that he might be back on "sizzurp" -- a topic of many of Wayne's songs.
The National Institute of Health lists seizures as one of the serious side effects of codeine. Overdosing on dextromethorphan, a main ingredient in cough medicine, can also lead to seizures.
Wayne, 30, whose real name is Dwayne Michael Carter Jr., was admitted to Cedars-Sinai Medical Center in Los Angeles Friday after suffering multiple seizures. Rumors of his imminent death began to swirl online after TMZ.com reported that he had been given last rites and his family was rushing to be by his side, after doctors had pumped his stomach three times in an attempt to flush substances from his system.
But Wayne's camp and the rapper himself quickly dispelled the rumors. Late Friday Wayne tweeted, "I'm good everybody. Thx for the prayers and love."
He was released from the hospital Monday, according to Mack Money, an associate of Wayne's record label Young Money.
Citing an anonymous source close to Wayne, Us magazine said Saturday that Wayne had overdone it with the "sippin syrup" concoction.
"He drank too much 'sizzurp' to get a better high," the source said. "He needs rehab but he's not close to death or anything. He's fine and just coming down off the high."
References to syrup are plentiful in Wayne's songs.
"Up in the studio me and my drank/Please let me be and let me do my thang/Thinkin about a certain ... certain somebody/That perfect somebody sexy purple body," he raps on "Me and my Drank."
In 2010, Wayne said that he gave up the drink. In a video posted online, the rapper said he was drinking Patron tequila and "RIP to the syrup."
Representatives for Wayne did not return ABC News' calls.
Dr. Jacqueline French, the president to of the American Epilepsy Society and a professor of neurology at NYU's Langone Medical Center, said there were several factors that could trigger seizures, including stress, if the brain was not receiving enough oxygen, not getting enough sleep and narcotics.
"Anything that compromises the brain can bring on a seizure," French said. "Certain drugs can lower the seizure threshold."
Dr. Dan Lowenstein, a professor of neurology at the University of California, San Francisco, said codeine, a sedative, would not necessarily be "pro-seizure" but that one of the concerns with cough syrup was that if it contained a stimulant, that could "offset the balance in the brain."
"There are a myriad of substances that can affect brain excitability and stimulants are one of them," Lowenstein said. "There are people who have a very low threshold for having seizures, and if they get exposed to the wrong combination of events, such as a stimulant drug and sleep deprivation, they then may develop a seizure and epilepsy."
Even still, the cause of Wayne's seizures remains unclear. But nonetheless, it has opened discussions for the dangers of "sippin syrup."