Heroin is sold in three different forms -- black tar heroin, brown powder heroin, and white powder heroin, and each contains slightly different ingredients.
What is sold as heroin is usually a mixture of diacetylmorphine and filler ingredients that share the appearance of heroin, some of which are other opiates, and share some of the psychoactive effects of heroin, and some of which are simply white powders or other cutting agents that share the appearance of the form of heroin it is cut with.
Heroin itself is made from morphine, a highly potent painkiller which occurs naturally in the latex sap of the seed pod of the opium poppy, known as opium. The opium poppy grows in many parts of the world, including Asia, Australia, some parts of Europe, most notably Turkey, Afghanistan, Colombia and Mexico. This opiate is the main psychoactive ingredient in heroin, which produces the heroin high.
Black tar heroin, which looks like a sticky or hard ball or chunk of blackish brownish substance, is produced by a very crude process, in which the opiate that is produced is relatively unrefined compared to white powder heroin. It contains several partially processed forms of opiate, which differ from heroin. Although black tar heroin has been around for over 100 years, its popularity in the United States began in the 1970s due to being cheaper and easier to make than white powder heroin. Further processing and cutting with lactose can produce brown powder heroin.
Street heroin may contain a variety of other street and prescription drugs, including methamphetamine. Although meth effects and heroin effects are in some ways opposite, meth being a stimulant and heroin being a relaxant, both produce euphoria, so a drug dealer can often get away with mixing any euphoria-producing psychoactive drug with heroin if it is available at a cheaper price. Meth carries its own risks and typically contains toxic chemicals.
The process of making diacetylmorphine or heroin from opium varies, depending on the methods used, and the facility for making it. These range from state-of-the-art legitimate laboratories run by fully qualified chemists, to clandestine labs run by illicit drug manufacturers, to makeshift processes using old oil drums and outdoor fires, run by local growers with little or no education in chemistry. Recently, heroin has been manufactered in home labs, by people attempting to convert prescription painkillers such as OxyContin into street heroin. When you buy heroin from a dealer, you have no way of knowing the original source of the heroin itself.
The heroin available through street dealers ranges from highly potent, carrying an increased risk of overdose, to highly impure and containing many contaminants. Some are by-products of the manufacturing process, which include chemicals such as calcium oxide, ammonia, chloroform, hydrochloric acid and acetic anhydride.
Street heroin may contain local anesthetics, such as xylocaine. Although anesthetics themselves are pure and legally used for medical and dental purposes, they do carry risks, may have side effects, and are potential allergens.
Filler ingredients are added to bulk up the heroin, so that dealers can increase their profit margin. They vary from benign substances, such as talc, flour, cornstarch, powdered milk and various sugars, to very harmful substances. For example, the tarry color and consistency of black tar heroin has led to the use of unusual diluents, including ground paper fiber soaked in black shoe polish. Quinine is sometimes added to white powder heroin for its bitter flavor. Dirt may be added to black tar heroin, leading to severe consequences -- see toxic ingredients below.
White powder heroin, in its purest form, is a salt form of the drug, known as diacetylmorphine hydrochloride, although it will typically be mixed or "cut" with other white powders, which reduce the potency, and increase the risk of contamination, and vein damage if the drug is injected. Typically, the purer the heroin, the whiter and shiner it appears, while the more heavily cut the heroin, the duller the white powder appears.
Although it is relatively rare for poisonous ingredients to be mixed into heroin, the dangers are severe, so you should seek medical help immediately if you or someone else has taken heroin and is experiencing adverse effects.
Strychnine is a toxic ingredient, sometimes mixed with heroin, that is used in rat poison and can cause death in humans. Psychological symptoms of strychnine poisoning include anxiety, restlessness, agitation and an increased startle response, and physical symptoms include jaw tension, muscle pain and spasms, rigidity of the arms and legs, and arching of the neck and back. Call 911 if these symptoms appear after using heroin.
Black tar heroin may be cut with soil, which can contain the spores of a toxic contaminant called Clostridium botulinum -- this has increasingly affected drug users in the United States and the United Kingdom over the past decade. If these spores get into a wound, which commonly occurs when injecting black tar heroin, they can germinate and cause wound botulism (WB). Even though the wound may appear small, the infection is extremely serious. Wound botulism produces local neurotoxins, which cause a symmetrical, flaccid, descending paralysis of the voluntary muscles -- meaning you can't move your muscles when you try, progressing to becoming unable to breathe without assistance, and eventually death if untreated. Call 911 if these symptoms appear after using heroin.
Contaminated black tar heroin has also been associated with cases of tetanus due to Clostridium tetani, necrotizing soft-tissue infections due to a variety of clostridia, and toxic shock syndrome previously reported to be characteristic of toxin-mediated Clostridium sordellii infection.
Brett, M., Hallas, G. and Mpamugo, O. "Wound botulism in the UK and Ireland." Journal of Medical Microbiology, 53:555–561. 2004.
CDC Facts About Strychnine. 14 May 2003. Retrieved 22 June 2011.
Frances, R., Miller S. and Mack, A. (Editors). Clinical Textbook of Addictive Disorders. 3rd edition. New York: Guilford. 2005.
Kimura, A., Jiga, J., Levin, R., Simpso, G., Vargas, Y. and Vugial, D. "Outbreak of Necrotizing Fasciitis Due to Clostridium sordellii among Black-Tar Heroin Users." Clinical Infectious Diseases 38:87–91. 2004.
National Drug Intelligence Center. Heroin Fast Facts. Product No. 2003-L0559-003. 2003.
Passaro, MD, MPH, D., Werner, MD, MPH, S., McGee, MSPH, J., Mac Kenzie, MD, W., and Vugia, MD, MPH, D. "Wound Botulism Associated With Black Tar Heroin Among Injecting Drug Users". JAMA 279:859-863. 1998.
PBS Online. "Tranforming Opium Poppies into Heroin." PBS and WGBH/Frontline. 1998.
Sobel, J. "Botulism." Clinical Infectious Diseases 41:1167–73. 2005.