Information about Drugs
The area of health care concerned with drugs and medicinal therapies is pharmacology. Health-care professionals who dispense prescription drugs are pharmacists, who may be registered pharmacists (RPh) or doctors of pharmacy (PharmD).
This section, “Drugs,” presents an overview discussion of pharmacologic concepts and entries about drugs and their use for the maintenance of health and the treatment of infection, injury, and disease.
Pharmaceutical Traditions in Medical History
The earliest written medical documents reference often elaborate preparations of botanicals used as medicines to treat a broad spectrum of ailments, ranging from HEADACHE and itching to weak PULSE and infected wounds. Healers in the times of ancient Babylonia, Mesopotamia, Egypt, and China relied on extensive collections of herbs, roots, barks, and seeds from which they concocted tinctures, teas, poultices, and other remedies. Ancient pharmacopeias outlined the formulations and uses of hundreds of plant forms for medicinal purposes.
ALCOHOL, too, was a major weapon in the early physician’s pharmaceutical arsenal, serving as a topical antibacterial as well as an ingested analgesic (PAIN reliever) and quasi-anesthetic. Opium poppies and coca leaves yielded the first NARCOTICS, opium and COCAINE. Coffee beans and tea leaves yielded CAFFEINE, a potent stimulant. Tobacco leaves, chewed or smoked, were the source of another powerful stimulant, NICOTINE. Coca leaves and tobacco leaves acquired such high value in some early cultures that they served as currency.
Today medicinal herbs and botanicals remain the mainstay of TRADITIONAL CHINESE MEDICINE (TCM) and form the foundation of the modern pharmaceutical industry. As many as 5,000 medicinal plants grow in various regions around the world, many in the rain forests of South America. About 25 percent of modern medicines trace their derivations directly or indirectly to plants. Laboratories now produce synthetic forms of many drugs once extracted from plants, such as the antiarrhythmia DRUG digoxin (digitalis from the foxglove plant), the pain reliever aspirin (salicin from the bark of the willow tree), and the antimalarial drug quinine (quinaquina from the bark of the chinchona tree). Other drugs, such as the anticancer drug paclitaxel (Taxol), which is an extract from the bark of the Pacific yew tree, still derive from their botanical sources.
Drug Controls and Regulations
The regulation of drugs—from effectiveness and safety to production and availability—that is the foundation of today’s pharmaceutical industry is a modern phenomenon. Until the early 20th century narcotics such as opium and HEROIN were freely available in the United States. Patent medicines (an odd assortment of liniments, elixirs, tinctures, nostrums, bitters, extracts, and compounds) dominated the druggist’s apothecary. From Lydia E. Pinkham’s Vegetable Compound, which contained far more alcohol than vegetable, to Mrs. Winslow’s Soothing Syrup, a sedating preparation of morphine, patent medicines claimed to treat just about any ailment ... and many claimed to treat just about every ailment.
The Pure Food and Drugs Act of 1906 was the beginning of the end for patent medicines; requiring medicine labels to list the product’s ingredients and spawning the federal oversight agency that was to become the US Food and Drug Administration (FDA). In 1938 the Food, Drugs, and Cosmetics Act extended the authority of the FDA to regulate the safety and therapeutic effectiveness (and labeling claims thereof) of drugs, requiring manufacturers to prove a drug’s safety before being allowed to market the drug. The regulations arose from the sometimes deleterious adulteration of drug products, brought to the forefront of public outrage when the use of poisonous wood alcohol in a sulfa preparation caused the deaths of more than 100 people. Shortly thereafter the FDA established separate classifications for prescription drugs and OVER-THE-COUNTER (OTC) DRUGS, prescription drugs being those whose safe use required a physician’s oversight and guidance and OTC drugs being those that individuals could safely use without the guidance of a doctor or pharmacist.
Drug advertising remained under the jurisdiction of the Federal Trade Commission (FTC) until the Drug Amendments of 1962, the first of several key amendments to the Food, Drugs, and Cosmetics Act. The 1962 Drug Amendments also gave the FDA the regulatory authority to require evidence of a drug’s safety as well as effectiveness before granting approval for the drug. The Dietary Supplements and Nutritional Labeling Act of 1994 drew back some authority from the FDA, however, reclassifying herbal and botanical products as dietary supplements and removing from FDA regulatory oversight.
Challenges in Pharmaceutical Therapy
Drugs have transformed health care over the past half century, relegating to insignificance many infections and diseases that in previous generations meant lifelong disability or early death. Drugs treat INFECTION, DIABETES, CARDIOVASCULAR DISEASE (CVD), kidney disease, LIVER disease, gastrointestinal disease, neurologic disorders, and cancer. Doctors in the United States write more than 14 billion prescriptions a year for nearly 3,000 different drugs, and another 2,000 medications are available in over-the-counter (OTC) products that are available without a doctor’s prescription. Indeed, there are few health conditions for which there are not pharmaceutical treatments. Nonetheless, significant challenges exist. Health experts worry that the expense of drugs puts them out of reach for many people who need them and that collectively people are developing habits in regard to drug therapies that ultimately put health at greater risk.
Drug costs and availability
Pharmaceutical manufacturers spend millions of dollars every year to develop new drugs. Yet as many as 20 promising drug concepts may die in the laboratory for every one that makes it clinical testing. For the length of time a drug remains under patent after its approval, an average of 14 years, the drug’s manufacturer has an exclusive piece of a multibillion-dollar market. Though few dispute a pharmaceutical company’s right to expect a financial return on its investment, the high cost of drugs still under patent makes the drugs unaffordable for many people. Older people take the hardest hit, caught in an intersection between increasing health-care needs and a fixed income.
One major effort to reduce drug costs is generic drugs, which are identical to their trade name counterparts (innovator drugs) in terms of active ingredients, DOSE, form, and efficacy (action in the body). The Government Accountability Office (GAO), the official expenditure watchdog of the federal government, estimates that generic drugs save Americans more than $10 million a year.
The high cost of drugs in the United States has fueled interest in purchasing drugs from countries in which they are not as expensive, such as Canada and Mexico. Although US law prohibits bringing imported drugs into the country, many people order them from Internet and mail-order sources nonetheless to save hundreds to thousands of dollars each year.
Patient compliance and lifestyle choices
Treating or preventing a health condition can be as easy as taking a few pills a day. However, though precise statistics are difficult to determine health experts estimate that perhaps half of people for whom doctors prescribe regular medications do not take them as directed. They may miss doses, combine drugs to consolidate dosages, take a reduced dose to “stretch” the prescription, or take the drug only when they feel symptoms. In some situations, however, taking a drug improperly is more of a health hazard than not taking the drug at all. The problem is significant enough to support a thriving secondary market that sells various “medication minder” methods. Unfortunately thousands of Americans require additional medical care for circumstances, including unintentional OVERDOSE, that develop as a consequence of failing to follow label instructions.
Health experts also worry that medications are becoming substitutes for healthful changes in lifestyle habits. For example, people who take drugs such as lipid-lowering medications may become complacent about making lifestyle changes that would allow them to stop taking the medication while reducing their risk for cardiovascular disease. Often it is easier to take the pill rather than to change EATING HABITS and exercise habits, another method for lowering blood lipid levels.
The first antibiotics, sulfa and penicillin, became lifesavers during and after World War II. Antibiotics put a rapid end to the often deadly infections rampant at the time, such as PNEUMONIA, TONSILLITIS, GONORRHEA, and TUBERCULOSIS. Within 25 years, however, infections began to appear that were resistant to penicillin, the most commonly used antibiotic, and doctors had to prescribe newly developed alternatives.
ANTIBIOTIC RESISTANCE emerged as a full-blown health issue in the latter decades of the 20th century with the appearance of multiple-drug-resistant infections of tuberculosis, gonorrhea, and pneumonia. By 2002 some strains of Staphylococcus aureus, a BACTERIA family accountable for a wide range of infection, including pneumonia and wound infections, had acquired resistance even to the most powerful antibiotic available, vancomycin. Of the most critical concern are NOSOCOMIAL INFECTIONS, infections that result from exposure to bacteria that thrive in environments such as hospitals and extended-care facilities. These bacteria have often evolved to a high level of multiple-drug resistance, making the infections they cause very difficult to treat.
Interactions among drugs
An estimated 30 million Americans take multiple prescription medications. Though these drugs keep potentially disabling or deadly health conditions in check, the risk for serious drug interactions increases exponentially with each additional drug. Factor in OTC drugs and herbal remedies, and drug interactions become more likely than not to occur. Such interactions can result in reduced or potentiated effectiveness of any or all of the drugs the person is taking. Doctors and pharmacists urge people always to tell each doctor who provides care, whether or not the doctor writes a prescription, about all drugs they are taking because sometimes the health problems that send them to the doctor result from interactions among their medications.
Breakthrough Research and Treatment Advances
Pharmaceutical research began to focus on pharmacogenomics the interactions between genetics and medications—in the 1990s. Doctors have known for quite some time that some people metabolize certain drugs more or less efficiently than do other people. This can result in altered efficacy. Researchers have been able to identify genes, some of which regulate CYTOCHROME P450 (CYP450) ENZYMES, the collective of enzymes that metabolize most drugs that enter the body. Subtle differences in protein encoding may slow or speed drug absorption, METABOLISM, or length of time in the BLOOD circulation. Particularly in areas such as cancer treatment, researchers are searching for ways to use pharmaceuticals to manipulate genetic encoding. Other research focuses on developing “smart” drugs, which specifically and narrowly target certain kinds of cells.