Understanding Drugs A New Interdisciplinary Course Mlldred H. Evans Erie Community College-South,
4140 Southwestern Blvd., Orchard Park, NY 14127
We are living in a drug-oriented world. Daily we are homharded with ads for "extra-strength" pain reliever, Brand X, which neutralizes more acid, or similar products. Many of us ingest our daily dose of caffeine each morning or "relax" with an inhalation of nicotine after dinner. For the ill and aging a vast spectrum of drugs is prescribed. Some people have a veritable drugstore of prescription and over-the-counter medications on their kitchen table or in their hathroom cahinet. To bring some understanding of the chemical make-up and physiological responses of some of these drugs and medications, my colleague, Mary Losi (who teaches anatomy and physiology) and I (a chemist) decided to organize alayman's interdisciplinary course, which we entitled "Understanding Drugs." Who Takes the Course While this course is being offered at our local community college, it has no prerequisites. No prior chemical or biological knowledge is presumed. The course is presented at a level that could he adapted to secondary school curricula. At our community college we have three sources of clientele for this course. First, the course is used as a science elective for nonscience curricula such as Business Administration, Secretarial Science, and Liberal Arts Social Science. Second, Allied Health students (students in Nursing, Medical Technology, pre-Medical, or pre-Pharmacy curricula) find this course helpful in preparing for subsequent pharmacy comes. The third source of students is the general public-adults or young people who take the course as a matter of personal interest. Course Credit and Gradlng Policies This one-semester course consists of three 50-min class periodslwk and earns the student three credits. Course grades are determined as follows: Weekly short answer quizzes are averaged. This quiz average is added to the three multiplechoice, hour exam grades and divided by four. A plot of the resulting final averages is used to determine letter grades for the course. Source Materials Materials covered on the quizzes and exams comes from a wide variety of sources: current journals, newspapers, pharmacology texts, medicinal chemistry texts, Food and Drug Administration publications, etc. A partial list of sources is included in the Bibliography at the end of this paper. The search for a satisfactory text continues. The closest we have come to the type of text we want is "Drugs and the Human Body: With Implications for Society" by Ken Liska. We have used this book as a reference text, omitting the "Implications for Society" since our course is designed to he a factual course rather than a "use-and-abuse'' course. We cover the physiological and chemical properties of the drugs and medications hut do not attempt to preach or moralize. In general, our students have little science background. To maintain their interest and to help them conceptualize the
Table 1.
Fllm Llst
Mr. Galen Comea to Town Roman physician visits modem drug stwe. (1971) 28 min.. color. Menell Dow Film Lit~ary,Merrell Dow PharmaceNicals Inc.. Subsbaii of the Dow Chemical Company, 1269 Gest Street, Cincinnati. OH 45203. Panem of Pain F a n professionalsdisuss pereeptimof p i n as rekted to the nervous sysmm. (1979) 28 mi"., cola. (Produced by Canadian Broadcasting Cap.) Filmakers Library. Inc., 133 East 58lh Street. Suite 703A. New York. NY 10022. FetalAlcohol Syndrome (1975) 13 min.. color. Film $21907. The Pennsylvania State University. Audb visual Services. University Park. PA 18802.
- -
R V r, .-.h n a r t.i.u.a Discuses me physiological effects of five classes of drugs: alcohol, opiates. stimulants, hallucinogens, marijuana. (1978) 29 min., color. Film $32172, The Pennsylvania State University, Audiovisual Services. University Park. PA 18802.
Valium A segmem of a "80 Minutes" pmgram repiing on Valium use. (1978) 18 min.. miat. Film $2-14125. Syracwe University Film Center. 1455 East Cobin Sbset Syracuse. NY 13210. FIX for Hope A shoR film depictingmat help is available fadepessed patients. 15 min.. cola. Film $15278. Modern Talking Picture Service, Film Scheduling Center. 5000 Park Sheet North. St. Petersburg. FL 33709. LSC-25 Chemical and physiological propdies of LSD. (1968) 27 min.. colw. Film #31254. The Pennsylvania State University, Audiovisual Services. University Park. PA 16802. Angel b a t h (Pm Shows physiologicalproperties of PCP. (1980) 33 mln.. color. Film $%15241. Syracuse University Film Center. 1455 East Colvin Street. Syracuse, NY 13210.
fundamentals, we sprinkle the course liberally with audiovisuals in the form of slides, transparencies, films, and filmstrip-cassette programs. A partial list of 16-mm films used is aiven in Table 1. It should he noted that some of the filmsused contain societal considerations. Sources that are strictly factual are rare. A few examples of material used in transparency form are included in Figures 1-3. Figure 1is used as a color transparencv to show the students what an onium wnnv looks like and ho; the green seed pod is scored to Lollect the opium exudate. Figure 2 is a reproduction of a turn-of-the-century advertisement for heroin and aspirin. Before 1912 heroin was marketed leeallv as a coueh sunoressant and nain reliever. At that time h;roi;l was thought he nonaddictive. Figure 3 which shows the similarity of codeine to morphine, is used as an example of structure-related activity. Examples of structures of drugs which hear similarity to neurotransmitters also are used in appropriate topic areas. For example we show how drugs such as am~hetaminesand halluciuonens mimic norepiGephrine.
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Volume 61 Number 6 August 1964
67 1
BAYER
ASPIRIN HEROIN The Sadstire for Cough",
Figure 1. Opium pappy. The graen seed pad scored to collect W e opium exmte is de~ictedat left WIII.
Reassuring the Student while Teaching Chemlstry Most students taking this course have a fear of chemistry. Constant reassurance is needed to remove their anxieties when they see com~licatedstructures such as those of mornhine. codeinr, or neurotransmitters. We do not expect memorization of such formulus but use them as illustrati~miof tho fact that many families of drugs have almost identical structures except for variance a t a particular position on the molecule. For example the replacement o f a n -OH group by an -OCH3 group - changes morphine t o codeine. Again, hicause so many students taking this course suffer from chemistry-anxiety, we have to "sneak" chemistrv into this chemistry/biology interdisciplineary course. For ins&ce, the course outline (Table 2) shows a section on Mild and Moderate Pain Relievers. This section includes the chemical make-up and physiological comparison of aspirin and acetaminophen (marketedunder trade names such as Tylenol@, Datril", etc.), medications which are widely used in overthe-counter (OTC) combination remedies. Manv of these OTC remedies also contain antacid suhstances. This gives us an o ~ ~ o r t u n ito t v~rovidesome chemical information about acids i d bases and ihe pH scale. Acids are defined as suhstances which provide H+ ions. Examples given include acetic acid (vinegar), CHBCOOH,citric acid in oranges and lemons, and hydrochloric acid, HCI, the "stomach acid" present in gastric juice in the stomach. Students learn that i t is normal for the contents of the stomach to be acidic and that the linine of the stomach is normally protected from attack by this k i d by mucous secretions. We explain that it is common to express the degree of aciditv in pH units which ranee rowhlv from 1for verv acidic y some &mmon subs&ces to 14 for basic suh&mce~~ i i d i t of substances are located on a diagram of the pH scale (vinegar a t about 3, coffee a t about 4, milk a t abo& 6, baking s k a (sodium bicarbonate) a t about 8, and household ammonia a t about 12. Neutral suhstances such as pure water would have a pH value of 7 on this scale. I t is explained that a substance with a pH of 6 is 10 times more acidic than pH 7; a substance with a pH of 5 is 100 times more acidic than pH 7; a substance with a pH of 4 is 1000 times more acidic than pH 7, etc. Thus gastric juice with a pH of 1to 2 is very acidic. Antacids are defined as substanceswhich are anti-acid, or substances which react with and thus remove H+ ions, I t is pointed out that sodium hicarbonate and calcium carhunnte are used as antacids, hut hnvr the disadvantage of promoting "acid rehound" in which the stomach srrrrtes additional gastric acid which nullifies the effect of the antacid. Addi672
Journal of Chemical Education
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FARBENFABRIKEN OF ELBERFELD CO. 40 Stone Street, N e w York, *ll.l.,.ll
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Figure 2. Old advwisement for heroin and aspirin.
MORPHINE
CODEINE Figure 3. Structures of morphine and codeine, emphasizing chemical similarity. tionally, sodium birarbonate should be avoided by penons on a low sodium diet. Aluminum hydroxideand magnesium hydroxide avoid the prohlem of arid retwund and are oftrn used together. V h e laxative effects of magnesium hydroxide (milk ofmagnesia) counteract the constipating effect of aluminum hydroxide.) Recent studies, however, have implicated aluminum ions injested in antacids as a possible causative factor in Alzheimer's disease. All of the above factors illustrate to the student the complexity of drug usage. The therapeutic henefits need to he weighed against the undesirable side effects.
Table 2.
Course Outline for UnderstandlnaDrum
I. Introdunion Brief Overview 01 Course Purpose and Contents.
11. Analpsics 1. The Cenual N e m u s System 2. The Neuron: Nature of the Nerve Impulse
3. The Nature and Measurement of Pain
4. Mild and MDderate Pain Relieving AgenO: Aspirin. Acetsminophen. and Related Compounds 5. Agents That Relieve Severe Pain: The Opiates (a) Opium and Its Derivatives: Morphine and Codeine (b) Semisynlhetic Narcotics Including Heroin (c) Synthetic Narcotics Including Methadone. Meperldine, and Fmpoxyphene (d) Antagonists (9) Endosenous Opiates
Ill. Factam Affecting Dmg Usage 1. Generic versus Brand Names 2. Administration Methods 3. Dosage. Side Effects, and Conhaindicatims
4. Drug Interactions (a) D w a r u s Interactions (b) DrusFaod Interactions (c) Drug-Smoking lntwactions 5. Allergic Reactions 6. Use of Physicians' Desk Retw-
IV. Depressants 1. Alcohol as a h u g 2. Anesthetics (a) General (b) Local 3. Barbiturate and Nonbarbiurate Sedatives and Hypnotics 4. Tranquilizws (a) Minw Tranquilizers (Antlanxiety Agents: Meprobamate, Valium. Libriuml (b) M 4 w Tranquilizers (Antipsychotics Including Thorazine) V. Stimulants 1. Antidepressants (a) Tricyclics (b) M A 0 lnhlbitors 2. Reflex Stimulants 3. Spinal Cord Stimulants 4. Cerebral Stimulants (a) Cocaine (b) Amphetamines (c) Xanthenes: Caffeine. Theobromine, Theophylline (d) Nicotine Vl. Hallucinogem 1. LSD, DMT, Psilocybin. Buf+ tenine 2. Mescaline (*om Peyote) and Related Compounds
3. PCP Vll. Cannabis: Mariiusna
ence
When we discuss opiates, we define alkaloids and show that the oresence of a nitroeen atom in these comoounds makes them bases (related to ammonia) arrd allows them M, react with an acid to form asalt. We mint out that this salt formation is extremely important because it makes these large molecules soluble in water. thus allowing them to be iniected with a hypodermic needle. Using a hall-and-stick model we show what a large, complicated molecule morphine is and that it is an asy&netric molecule. This asymmetry is likened to aleft hand. We show that an asymmetric object such as a left hand has a mirror image--the right hand. We explain that just as the left and right hands are mirror images, so, too, asymmetric molecules such as morphine also exist as mirror images, one of which is called the (-)-isomer and the other which is called the (+)isomer. Then using a pair of gloves it is shown that the left hand will fit into the left glove, but not into the right This infor- glove. . mation is likened to a drug fitting into a receptor site. Morphine isolated from the opium poppy is the (-)-isomer. I t is physiologically active because it fits the morphine receptor sites in the body. ArtificiaUy synthesized (+)-morphine does not fit the receptor site Gust as your right hand does not fit your left glove) and, therefore, is not pharmacologically active. Other chemical principles are similarly inserted in appropriate spots. Summary This interdisciplinary course covers the chemical and physiological properties of selected drugs and medications. Since students in the course are mostly nonscience majors, ~ extensive use of audiovisuals and a relaxed avoroach h e l to overcome their science anxiety. The health o&tation ofthe course lends relevance.
Acknowledgment I thank my colleague, Mary Losi, for her encouragement, stamina, and congeniality during the planning phases of the course and in our team-teaching experiences. Thanks also to Lawrence Seyfried for his assistance in the administrative processes of new-course approval.
Angel. Jack E.. (publisher). "Phyaidana' D e k Reference: 37th ed.. Medical EEoaomies Company, Oradell, NJ. 196.3. Andre&, JiU H., "Chaoslng the Right Aspitin Can Be a Pain," C a ~ u m e r aDigost. 11, (JanuaryiFebruary, 1982). "Aspirin: Is Bayer Better: Conrumer Reports, 347 (July 1982). ~ a * e r charies~., , JI. (pubrieher),"~hysicians'~ek~efrence for~onpreseriptianm ~ , " 2nd ed., Medical Eeonomica Compsny, Oradell, NJ, 1981. Bany, Brian W.."DTU~Delivery Systems: Chernfoeh. 38 (Jsnuary 1983). 40 Clark, Matt. Shspim. Dan, and Lindsay. J o b J., "Atterm New Inaight=,"Ne~uawe~k. (August 23,19321. h t a n m . James, and Banks, Yvetta. "What toEat and Not to&t WhenTaLing Modication: O w d Housaheeping. 1% (July 1982). 1983). "Cough Remedies: Which On- Work Beat?" ComumerRoporta.59 (FebDunean,David,and Goid, RoberZmDmgsandthe Whol~Person,"John Wilev&Sone, Near York, 1382. D W ~ ~orothy, , and Girdano, Daniel A,. "mugs-A FactualAceouni," 3rd ed., AddisionWesley PublishingCo., Reading, MA, 1980. Editma of Consumer Guide with Nimla Giacona, "Proscription Drugs: PuhlicationaInternstionel, Ltd..Skokie, IL,1983. Engs.Ruth C., "Responsible Drug and AleohalUa%"MaunillanPuhlishingCo.,lnc., Near York, 1979. FDA Consumer, Department of Healthand HumanSeNices.PuhiicHealthService,Fmd end Drug Adminiatration, Office of Public Affairs, Raekville. MD (Many different reprints fmm this journal are used.) Gerald. Michael C.."Pharmaeolaev-An lntrodudion to Drum," 2nd ed., Prentice-Hall, I..., ~ " ~ 1 - cliffa, d ~~,ig81. Gmedon, Ja, "ThePeoplek Pharmacy-2," AwnBmks, Near York, 1980. ~itt. w . . d ~ ~ ~ ~.."~hemistn~~d~~h:a~~lg~~b~ishiog~a..~io~ t . ~ ~ ~ ~ t h ~ nrapoliolis. MN. 1978. Hoffman. Phllio C.. '"Meehaniama of h e Action." NSF Chautauoua Short Comas for the ~dvaneementof ~ & g e +eacbera, conducted by t h e v h n c & h i a t i o n i& Science,Temple Univ.. Philadelphia,PA, Mareh 196.3."HoarToChAn Antacid," Consumer Reporfe. 412 (August 1983l."SameBiaehwistry ofSedati~a: J. Olar EDUC. 56,402 (1979). Jon=-Witten, Pstrieia, and Wittera, We1don;'hgsandSaeiety-ABiologicalPerapective: Wsdawarfh. he.. Belmont, CA. 1983.
Volume 61 Number 8 August 1984
673
Julien, Robert M.,"APrimer of DrugAnion,"3rded., W. H, heeman and Company, Ssn Franciaeo, CA, 1981. Korolkouss, Andrejus, and Burckhalter. Joseph H.,"Fmmtials of Medicinal Chemistry,' John Wiley 8 Sons,Inc.. New York, 1976. Levins, Ruth R.,"Pharmaeology: Drug Actions and Reactions," 2nd ed., Little, Brown and Company, Boston. 1978. Krieger, Dorothy T.."Brian Psptidea: Whet, Where, and When," Seiems.975 (ZDeeembu ,9119,
Liska, Ken. "Drugs and the Hum= Body-With Impllcationa for Soeicty," Maemillan Publishing Co., NewYork, 1981. Long, James W., M.D., "The Eracntial GuidetnPresoiptbn Drugs." 3rd ed., H w e r and R o w , Publishers, New Yark, 1982. Marry, Robert I.. "Human Physiology? 2nd ed., Prentiee-Hall, Ine.. E"g11woad Cliffs, NJ, 1975. Morganthau, Tam, C o p ~ ~ lVmnnt. a. Pate, James L., Abmmaob Pamela. Shannm, Elaine. and Fmte, Donna. "Guns, Gras-and Maney,"Nemsweok, 36 (October 25,1982). W ,and Godbey. Asa L.."HowYou Can Ne*n, Marian, Godbey,Kamlyn,Ncwton,David Improve the Effechuenesa of Psychotropic Drug Therapy." NurmLg 78. 46 (July 1WP)
Niear. Michael J.. "Marijuana Use and Abuse," Chemistry. 17 (January 1979). Personal Business Supplement, "Ancsthek New Ways," Busineaa Week, 166 (February 15,1982).
674
Journal of Chemical Education
"PillsThat Compete With Aspirin: C o ~ u m eReports. r 395 (August 1982). Plat< W e r i r i W.. "Better Home+ and Garden. Handbook of C a m o n Medicines," Meridith Carp., Den Moinea, IA, 1980. Reed, T. Edward, "One Man's Tipple is Another Man's Poimn,"Neu Scientist, 748 (8 Dccemher 1983) Rodman, Morton J.,"The Drug Interactions We All Overlmk," RN, 61 (April 1981). Rodman, Morton J.. "Underatanding Mediations: The Haws and Whys of Drug Therapy," Medical Economics Company. Oradell, NJ, 1981. Stern. Edward L. "Praeri~tionDrum and Their Side Effects." Gr-tsndDuolao. . New York, 1975. Stine, William R., "Amlied Chemistry," 2nd ed., Allw and Bscon, he., Baston, MA. 1981. "The Merck Index, An Encycloped~aof Chemistry and Drum," loth ed., M a c k and Co.. Inc., Rahway, NJ, 1983. U q . S~lly."No-nameDrugsAreMakingaNameforThemseluea,"ChomicolMorksting Reports, 9 (March 7,1983). Waaan, John. "Natural and Synthetic Nmotie Dmge," Amatiron Scientist, 69, 318 (1981). Drugs," GoodHousekee~ing.77 2immerman.David R.. "AGuide to 100 Nonp-iption (April 1983). ZoUer,Uri, and Weias,Shhana. "Hashishand Marijuans, C h e m k b y h the SocialSew+ce Curriculum: J. CHEM EDUC.,58.42 (1981).
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