opium, substance derived by collecting and drying the milky juice in the unripe seed pods of the opium poppy, Papaver somniferum. Opium varies in color from yellow to dark brown and has a characteristic odor and a bitter taste. Its chief active principle is the alkaloid morphine, a narcotic. Other constituents are the alkaloids codeine, papaverine, and noscapine (narcotine); heroin is synthesized from morphine. Morphine, heroin, and codeine are addicting drugs; papaverine and narcotine are not. A tincture of opium is called laudanum; paregoric is a mixture of opium, alcohol, and camphor.

Effects and Addictive Nature

Opium and its various constituents exert effects upon the body ranging from analgesia, or insensitivity to pain, to narcosis, or depressed physiological activity leading to stupor. Opium users describe experiencing a feeling of calm and well-being. Opium addicts in otherwise good physical and mental health whose drug needs are met are thought to experience no debilitating physiological effects from their addiction, although there is some evidence that immune function is compromised. However, their preoccupation with the drug and its acquisition can lead to malnutrition and general poor self-care and an increased risk of disease.

Medical Uses

Opium was commonly used as an analgesic until the development of morphine. Morphine continues to be prescribed for relief of severe pain, but fears of its addictive potential have limited its use. Laudanum was used in the 1800s to promote sleep and alleviate pain; codeine suppresses coughing; paregoric stops diarrhea. Medicinal opiates were freely available in the United States and Europe in the 19th cent., and the number of addicted people surged as a result.

History

The medicinal properties of opium have been known from the earliest times, and it was used as a narcotic in Sumerian and European cultures at least as early as 4000 B.C. The drug was introduced into India by the Muslims and its use spread to China. Early in the 19th cent., against Chinese prohibitions, British merchants began smuggling opium into China in order to balance their purchases of tea for export to Britain, an act that set the stage for the Opium Wars. Chinese emigrants to the United States, who were employed to build the transcontinental railroad, brought the opium-smoking habit to the West Coast.

During the 19th cent. opium was grown in the United States as well as imported. Besides indiscriminate medical use, opiates were available in the United States in myriad tonics and patent medicines, and smoking in opium dens was unhindered, resulting in an epidemic of opiate addiction by the late 1800s. The generous use of morphine in treating wounded soldiers during the Civil War also produced many addicts.

Importation of opium by Chinese nationals was prohibited in 1887; in 1906 the Pure Food and Drug Act required accurate labeling of patent medicines. The Harrison Narcotics Act of 1914 taxed and regulated the sale of narcotics and prohibited giving maintenance doses to addicts who made no effort to recover, leading to the arrest of some physicians and the closing of maintenance-treatment clinics. Since then, numerous laws attempting to regulate importation, availability, use, and treatment have been passed, and the concern with opium addiction per se has largely been replaced by concern with heroin, cocaine, marijuana, and other illegal drugs.

Large quantities of opium are still grown, some for legitimate use, on opium poppy farms in Southeast Asia (the "Golden Triangle," primarily in Myanmar), Southwest Asia (primarily Afghanistan and Pakistan), and Latin America (primarily Colombia). The opium gum may be crudely refined and smoked (e.g., "brown sugar") or converted to morphine and heroin. Growers usually make more for opium than for other crops, and the cultivation and refining employ hundreds of thousands of people, but the real profits go to the drug traffickers. It is estimated that the street price for heroin is 153 to 183 times that of the opium bought from the farmer. Despite laws and agreements to control its use, a worldwide illicit opium traffic persists.

See also drug addiction and drug abuse.

Opium Wars, 1839-42 and 1856-60, two wars between China and Western countries. The first was between Great Britain and China. Early in the 19th cent., British merchants began smuggling opium into China in order to balance their purchases of tea for export to Britain. In 1839, China enforced its prohibitions on the importation of opium by destroying at Guangzhou (Canton) a large quantity of opium confiscated from British merchants. Great Britain, which had been looking to end China's restrictions on foreign trade, responded by sending gunboats to attack several Chinese coastal cities. China, unable to withstand modern arms, was defeated and forced to sign the Treaty of Nanjing (1842) and the British Supplementary Treaty of the Bogue (1843). These provided that the ports of Guangzhou, Jinmen, Fuzhou, Ningbo, and Shanghai should be open to British trade and residence; in addition Hong Kong was ceded to the British. Within a few years other Western powers signed similar treaties with China and received commercial and residential privileges, and the Western domination of China's treaty ports began. In 1856 a second war broke out following an allegedly illegal Chinese search of a British-registered ship, the Arrow, in Guangzhou. British and French troops took Guangzhou and Tianjin and compelled the Chinese to accept the treaties of Tianjin (1858), to which France, Russia, and the United States were also party. China agreed to open 11 more ports, permit foreign legations in Beijing, sanction Christian missionary activity, and legalize the import of opium. China's subsequent attempt to block the entry of diplomats into Beijing as well as Britain's determination to enforce the new treaty terms led to a renewal of the war in 1859. This time the British and French occupied Beijing and burned the imperial summer palace (Yuan ming yuan). The Beijing conventions of 1860, by which China was forced to reaffirm the terms of the Treaty of Tianjin and make additional concessions, concluded the hostilities.

Organic compound, a narcotic drug known since ancient Greek times, obtained from exuded juice of immature fruit capsules of the opium poppy. Opium has legitimate medical uses, as the source of the alkaloids codeine and morphine and their derivatives. It is also used illicitly, either raw or purified as alkaloids and their derivatives (including heroin). Opium alkaloids of one type (e.g., morphine, codeine) act on the nervous system, mimicking the effects of endorphins; they are analgesic, narcotic, and potentially addicting (see drug addiction). Those of a second type, including papaverine and noscapine, relieve smooth muscle spasms and are not analgesic, narcotic, or addicting. Habitual opium use produces physical and mental deterioration and shortens life. Overdose can cause death by depressing respiration.

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Two trading wars of the mid-19th century in China. The first (1839–42 was between China and Britain, and the second (1856–60; also called the Arrow War or Anglo-French War) was between China and a British-French alliance. Trade developed between China and Western countries from the late 16th century. The Chinese, accustomed to tributary relationships with others, required that Westerners pay for Chinese goods with silver currency. To offset a growing negative flow of silver at home, the British created a market for opium in China and began importing it there illegally. As demand for opium grew, China tried to stop the practice, and hostilities broke out. Britain quickly triumphed, and the resultant Treaty of Nanjing (Nanking;1842; the first of a series of unequal treaties between China and Western countries and, eventually, Japan) was a blow to China. The outbreak of the second war resulted in the Treaty of Tianjin (Tientsin; 1858), which required further Chinese concessions. When China refused to sign subsequent treaties, Beijing (Peking) was captured and the emperor's summer palace burned. The overall result of these conflicts was to weaken the Chinese imperial system, greatly expand Western influence in China, and pave the way for such uprisings as the Taiping and Boxer rebellions. Seealso Canton system; British East India Company; Lin Zexu.

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