Terms such as analogues and immediate precursor were included in the legislation in an attempt to keep abreast of and deal with chemical derivatives of controlled drugs, which are synthesized to circumvent scheduling and hence not be considered illegal. Another component of the 1990 legislation was the provision of emergency scheduling as a method of combating emerging designer drugs. If a drug or chemical is deemed to be an imminent hazard to public safety, the substance can be scheduled without administrative delay. This provision of the bill has been invoked many times, for example when chemical modifications of “bath salts” chemicals and synthetic marijuana made their way into the drug abuse world. The Uniform Controlled Substances Acts are actually successors to earlier laws such as the Harrison Narcotics Tax Act of 1914 and the Uniform State Narcotic Drug Act of 1934, which dealt with what we now refer to as controlled substances. In reality, the first government attempt to regulate drugs in the United States occurred with passage of the Pure Food and Drug Act of 1906 (FDA, 2019b). The act was designed to prevent the manufacturing, selling, and transporting of adulterated, misbranded, poisonous, or deleterious foods, drugs, medicines, and liquors. Prior to the Pure Food and Drug Act, labels on patent medicines were full of glowing endorsements of what these medicines could cure, but disclosed no information about their ingredients. Such patent medicines or “nostrums” often contained unregulated amounts of cocaine, opium, morphine, and even heroin. These early examples of legislation regulating food and drugs were essentially the beginnings of the FDA in the United States (FDA, 2019b). Although, technically speaking, drug regulation was first begun under the Pure Food and Drug Act, this legislation was primarily a “labeling law.” It did not address two important subjects: drug safety and efficacy. These important subjects were not addressed until much later under the Food, Drug and Cosmetic Act of 1938 (drug safety; FDA, 2018b) and the Kefauver-Harris Amendments of 1962 (efficacy; Greene & Podolsky, 2012). The first legislation dealing with what are now called controlled drugs was the Harrison Narcotics Tax Act of 1914. The purpose of the act was: To provide for the registration of, with collectors of internal revenue, and to impose a special tax upon all persons who produce, import, manufacture, compound, deal in, dispense, sell, distribute, or give away opium or coca leaves, their salts, derivatives, or preparations, and for other purposes (Harrison Narcotics Tax Act, 1914a). Far from being a prohibition law, the Harrison Narcotics Tax Act was instead a law for the orderly marketing of opium, morphine, heroin, and other drugs – in small quantities over the counter and in larger quantities on a physician’s prescription. Indeed, the
right of a physician to prescribe was spelled out in apparently unambiguous terms: Nothing contained in this section shall apply … to the dispensing or distribution of any of the aforesaid drugs to a patient by a physician, dentist, or veterinary surgeon registered under this Act in the course of his professional practice only (Harrison Narcotics Tax Act, 1914b). Registered physicians were required only to keep records of drugs dispensed or prescribed. Because the Harrison Narcotics Tax Act was primarily a revenue-producing act, the Conference of Commissioners on Uniform State Laws developed the Uniform State Narcotic Drug Act in 1934. This act was written to make the law uniform in various states with respect to controlling the sale and use of narcotic drugs. The commissioners intended to effectively safeguard and regulate narcotic drugs throughout all the states. Until passage of the Uniform Controlled Substances Act of 1970, the use, taxing, and distribution of narcotic drugs was regulated by the legislative acts of 1914 and 1934. Two important laws were enacted between 1934 and 1970 that did not deal specifically with controlled substances, but rather with the safety and efficacy of drug products. The Food, Drug, and Cosmetic Act of 1938 extended the labeling requirements of earlier laws to include proof that the drug was safe. After years of legislative turmoil in the 1930s, a series of deaths attributed to elixir of sulfanilamide helped to bring this legislation to fruition (Wax, 1995; West, 2018). Sulfanilamide, an early sulfa drug, was safe. However, a concoction designed for pediatric consumption used a toxic chemical, diethylene glycol, to dissolve the drug. The provisions of the 1938 legislation were quite extensive, but still did not require a drug to be effective; it needed only to be safe. In 1962, in response to the birth defects caused by thalidomide in several countries, the passage of the Kefauver-Harris Amendments was accomplished (FDA, 2012; Tantibanchachai, 2018). These amendments stated that a drug had to be safe and effective for the specific disorder for which it was marketed. Moreover, the amendments essentially established the FDA as the government entity that had to grant approval before any human trials of a drug could be approved. Although a discussion of all the legislation enacted in the past century to control prescription drugs is beyond the scope of this course, one final item relating to controlled substances should be mentioned. The Anabolic Steroids Control Act of 1990 added anabolic steroids to the list of controlled substances as Schedule III drugs in response to extensive abuse of these drugs in sports. The Anabolic Steroid Control Act of 2004 added prohormones (hormone precursors) as Schedule III drugs. The Designer Anabolic Steroid Control Act of 2014 added new designer anabolic steroids to the list (Council for Responsible Nutrition, n.d.).
PHYSIOLOGY AND PHARMACOLOGY OF DRUG ABUSE
Drugs may stimulate or inhibit neurotransmitter release, mimic neurotransmitter action, block receptors, inhibit metabolizing enzymes, or block presynaptic reuptake. Drug abuse (including abuse of prescription drugs) often involves interactions in various “reward systems” in the brain, often involving the neurotransmitter dopamine. The three most commonly abused prescription drug categories produce activity in one or more of the reward areas of the brain (as do nonpharmacological rewards such as food, music, and sex). displace stored neurotransmitters from adrenergic nerve endings or they inhibit the reuptake of neurotransmitters already released – either way increasing synaptic residence time and the amount of adrenergic receptor interactions. For the most part, therapeutically available stimulants are indirect-acting agents that displace stored neurotransmitters. In contrast, the most common illicit stimulant, cocaine, is an indirect-acting chemical that inhibits neurotransmitter reuptake.
The brain is a communication center consisting of billions of neurons. Neuronal networks pass messages back and forth to different structures within the brain, the spinal cord, and the peripheral nervous system. Communication between neurons is accomplished by release of neurotransmitters from presynaptic neurons that pass through a cleft or gap ( synaptic cleft ) and bind to receptors on the postsynaptic neuron. Neurotransmitter activity is terminated by synaptic enzymes or by reuptake into the presynaptic neuron. Virtually all drugs that work in the brain do so by affecting this system in one way or another. sympathomimetics . These agents mimic the effects of the sympathetic nervous system, which causes the fight or flight response in the body (e.g., increased heart rate, pupil dilation). They mimic both central and peripheral effects of adrenergic agonists such as norepinephrine and dopamine, either directly or indirectly. Direct-acting agents specifically interact with and activate adrenergic receptors. Indirect-acting agents either Stimulants Pharmacologically, stimulant drugs are classified as
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