Cheese (recreational drug)

"Cheese" is a heroin-based recreational drug that came to the attention of the media inside and outside the United States after a string of deaths among adolescents in the Dallas-Fort Worth Metroplex, between 2005 and 2007. As of 2012 the drug use is now among older people who were teenagers around the period the drug was first discovered.

Cheese is a combination of drugs, made by combining heroin with crushed tablets of certain over-the-counter cold medication, such as Tylenol PM. Such cold medications contain acetaminophen (paracetemol), the active ingredient in Tylenol, and the antihistamine diphenhydramine, the active ingredient in Benadryl. Cheese samples obtained in north Dallas contained between 2% and 8% heroin, in contrast to the 30% commonly found in black tar heroin. Users commonly take the powder by insufflation ("snorting") rather than by intravenous injection. This mixture is also known as "Tylenol With Smack", by analogy to the Tylenol With Codeine series.

Due to the high concentrations of non-opiate substances relative to the diamorphine content of the drug, abuse and overdose of cheese are more dangerous than pure-form opiate overdoses. Emergency personnel must address the overdose effects of each component of the drug, since the contents and concentrations of each component vary widely among batches they must wait for either the completion of the toxicology report to begin treatment or wait for the effects of each drugs overdose to manifest. The acetaminophen content of the drug induces severe, irreversible damage to the liver when taken in high doses for long periods of time. Very high doses of acetaminophen are capable of producing acute liver failure and death within hours, patients who survive this acute phase of the toxicity generally require dialysis and eventually a liver transplant. Due to the many methods of preparation a user can not know how much acetaminophen is in any given batch and therefore can not reliably determine a safe dose. A dose of the last batch which produced no toxic effects may produce lethal effects in the next batch.

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