Drugs dictionary

Opium

There were no legal restrictions on the importation or use of opium until the early 1900s. In the United States, the unrestricted availability of opium, the influx of opium-smoking immigrants from East Asia, and the invention of the hypodermic needle contributed to the more severe variety of compulsive drug abuse seen at the turn of the 20th century. In those days, medicines often contained opium without any warning label. Today, there are state, federal, and international laws governing the production and distribution of narcotic substances. Although opium is used in the form of paregoric to treat diarrhea, most opium imported into the United States is broken down into its alkaloid constituents. These alkaloids are divided into two distinct chemical classes, phenanthrenes and isoquinolines. The principal phenanthrenes are morphine, codeine, and thebaine, while the isoquinolines have no significant central nervous system effects and are not regulated under the CSA.

Morphine

Morphine is the principal constituent of opium and ranges in concentration from 4 to 21 percent. Commercial opium is standardized to contain 10- percent morphine. In the United States, a small percentage of the morphine obtained from opium is used directly (about 20 tons); the remaining is converted to codeine and other derivatives (about 110 tons). Morphine is one of the most effective drugs known for the relief of severe pain and remains the standard against which new analgesics are measured. Like most narcotics, the use of morphine has increased significantly in recent years. Since 1998, there has been about a two-fold increase in the use of morphine products in the United States. Morphine is marketed under generic and brand name products including MS-Contin®, Oramorph SR®, MSIR®, Roxanol®, Kadian®, and RMS®. Morphine is used parenterally (by injection) for preoperative sedation, as a supplement to anesthesia, and for analgesia. It is the drug of choice for relieving the pain of myocardial infarction and for its cardiovascular effects in the treatment of acute pulmonary edema. Traditionally, morphine was almost exclusively used by injection. Today, morphine is marketed in a variety of forms, including oral solutions, immediate and sustained-release tablets and capsules, suppositories, and injectable preparations. In addition, the availability of highconcentration morphine preparations (i.e., 20-mg/ml oral solutions, 25-mg/ml injectable solutions, and 200-mg sustained-release tablets) partially reflects 20