DH 236 Ch. 1 Pharmacology Introduction PDF

Pharmacology DH 236 Chapter 1 Information Sources, Regulatory Agencies, Drug Legislation Ruth Bushby, R.D.H., Med., BScDH, dip. D.H. Pharmacology for the Dental Hygienist 9th Edition  Course Learning Outcomes 1. apply the general principles of pharmacology i...

Pharmacology DH 236 Chapter 1 Information Sources, Regulatory Agencies, Drug Legislation Ruth Bushby, R.D.H., Med., BScDH, dip. D.H. Pharmacology for the Dental Hygienist 9th Edition  Course Learning Outcomes 1. apply the general principles of pharmacology in a clinical setting in order to provide safe client care – 1.1 discuss the history of pharmacology and its relationship to the oral health care provider – 1.2 define the ways in which drugs are named and the significance of each – 1.3 describe the acts and agencies designed to regulate drugs – 1.4 identify the phases of clinical evaluation involved in drug approval and the drug schedules – 1.5 describe the elements of a drug prescription  History Pharmacology began when human ancestors noticed that ingesting certain plants altered body functions and awareness  Ancestors From humans’ earliest beginnings the use of medicinal plants has been a part of the Indigenous people’s healing traditions worldwide. Indigenous peoples have identified over 400 different species of plants (as well as lichens, fungi and algae) with medicinal applications.  Indigenous Medicines When Europeans and other newcomers arrived in Canada, they quickly learned about and adopted many of the plant medicines used by Indigenous peoples. One famous example is how French explorer Jacques Cartier and his crew, suffering from scurvy when they were overwintering what is now called Quebec City) in 1536, were saved by local Haudenosaunee. The Haudenosaunee brought them a coniferous tree (which Cartier named “tree of life”) and told them how to prepare it as a medicine.  Indigenous Medicines In turn, Indigenous peoples in Canada learned to use medicines from Europe and other parts of the world – latex of the common dandelion (Taraxacum officinale) to remove warts – fragrant pineappleweed (Matricaria discoidea) to make a medicinal tea  Indigenous Medicines New diseases were also introduced by the Europeans, not originally known or widespread in Canada, but soon after European contact, spread in epidemic proportions among the Indigenous populations. – Smallpox, measles, tuberculosis, and some venereal diseases Existing medicines were applied to treat these new ailments, and in some cases new medicines were developed. – Sweetflag (Acorus americanus), already an important medicinal plant of the boreal forest region and eastern Canada, was used to treat smallpox. – Barestem lomatium (Lomatium nudicaule), was used to treat tuberculosis. – Inner bark of devil’s-club (Oplopanax horridus, a shrub in the ginseng family, Araliaceae), is now used to treat Diabetes which is now prevalent among Indigenous populations.  Indigenous Medicines Medicinal plants are treated with great reverence and respect, in acknowledgement of their gifts and service to people. Healers carefully prepare themselves for their work, and follow strict cultural protocols relating to harvesting, preparing and administering their medicines. Con College Indigenous Garden Research: Jerusalem Artichoke Research: Sweet Grass, White Cedar and Anise Hyssop Research: Sugar Maple, Tamarack and Purple Corn Flower  Pharmacology Pharmacology – Pharmaco “drug” or “medicine” – logy “study” The study of drugs & their effects on living organisms What is a drug?  A drug is…………. Chemical compound with a specific chemical structure Medically, it is defined as a therapeutic agent in the prevention, diagnosis, alleviation, treatment & or cure of disease Drugs produce effects by influencing the cells of the body  According to Canada’s Food and Drugs Act A drug is…………. Defines: as any substance or mixture of substances manufactured, sold or represented for use in: a) the diagnosis, treatment, mitigation or prevention of a disease, disorder or abnormal physical state, or its symptoms, in human beings or animals; b) restoring, correcting or modifying organic functions in human beings or animals; or c) disinfection in premises in which food is manufactured, prepared or kept. Drugs can be prescription or non-prescription. Are herbs Drugs? Minerals? Vitamins?  Prescribed and Dispensed Disciplines that can prescribe and dispense (may have restrictions/guidelines according to province/state) Physicians Veterinarians Dentists Dental Hygienists – Chlorhexidine & Fluoride Optometrists Nurse Practitioners Pharmacists  Role & Responsibility of the Dental Hygienist 1. As a health care provider we must have foundation knowledge (pros & cons) We must be aware of the relationship between the tasks & learning: Foundational knowledge For example: What is the connection between plaque & calculus if the client has a heart valve replacment?  Importance of Foundational Knowledge of Pharmacology Professional Competency (Be Able Foundation Knowledge to) Dental Hygienist Debridement of biofilm Does the client have a and calculus history of any cardiac conditions associated with Infective Endocarditis (IE)? Dentist Extraction of a tooth Does the client have a history of any cardiac conditions associated with Infective Endocarditis (IE)? Do these clients need prophylactic antibiotics?  Infective Endocarditis (IE) Also called bacterial endocarditis (BE), is an infection caused by bacteria that enter the bloodstream and settle in the heart lining, a heart valve or a blood vessel. IE is uncommon, but people with some heart conditions have a greater risk of developing it. Invasive dental procedures cause bacteremia, which can be complicated by infective endocarditis in those at increased risk of the disease Antibiotic prophylaxis reduces the incidence of bacteremia, but high level studies confirming that this reduces the incidence of infective endocarditis are lacking  Joint Replacements The evidence-based 2016 COA/CDA/AMMI “Consensus Statement on Patients with Total Joint Replacements having Dental Procedures” states that routine antibiotic prophylaxis is not indicated for clients with total joint replacements, nor for clients with orthopaedic pins, plates, and screws. For considerations on whether prophylactic antibiotic coverage is required or recommended for a specific medical condition (whether related to joint replacement or not), consult the CDHO Knowledge Network. – Consult with orthopedic surgeon Consult the Joint Replacement Fact Sheet; the vast majority of clients with prosthetic joints do not require, nor are recommended to be given, prophylactic antibiotics. CDHO antibiotic prophylaxis for the prevention of infective endocarditis and hematogenous joint infection  Table 2 Note: Prior or ongoing antibiotic use for another condition should be considered before prophylactic antibiotics are prescribed, because resistant organisms may develop. If the need for prophylaxis closely follows prior antibiotic exposure or is coincident with ongoing antibiotic use, a prophylactic antibiotic from a different antibiotic class is likely indicated.  (Role & Responsibility continued) 2. Health History: *medications must be listed *allergies are noted *avoid interactions during dental procedures *educate the client - antibiotics - upset stomach? birth control less effective? - calcium channel blockers for hypertension –xerostomia? - Aspirin to prevent heart attack & stroke – increase in gingival bleeds? - BCP may cause gingivitis? * allows us to provide the best care for client/client doesn’t understand relationship of systemic disease & oral health  ensure that medical emergencies are avoided  “follow up” on yes responses & use “open ended” questions For example: Do your gums bleed? Why do you think they bleed?  (Role & Responsibility) 3. Administration of Drugs in Dental office Knowledge of these drugs is crucial *fluoride/chlorhexidine *local anesthetics-may react with marijuana, amphetamines & cocaine (epinephrine may cause increase in BP and tachycardia) * NO2- contraindicated in pregnancy - spontaneous abortion & birth defects *antibiotics – BCP, candidiasis *interventions to manage oral side effects of medications Saliva replacement therapy, antifungal, lidocaine rinse, topical ointments (Zovirax) 4. Emergencies: Knowledge on how to prevent, recognize and handle emergencies * CPR & anaphylactic shock * Latex allergy 5. Appointment scheduling: Special handling * Asthmatics in the P.M.- less stress * Diabetics 1-11/2 hrs. after meds. taken if morning appt. *Latex-free 6. Nonprescription Medication: Self medication - OTC drugs – Nutriceuticals *Can cause adverse effects and interactions with other drugs *Antihistamines, decongestants & relationship to BP, chronic xerostomia & may need position adjustment *Most “nutriceuticals” are dietary supplements, although a smaller percentage are medical foods and food additions 7. Nutritional or Herbal Supplements: Self-Medication or Prescribed *Although vast majority do not have FDA approval may clients sue them *Can cause adverse effects and interactions with other drugs *Clients can forget to report these OTC drugs A thorough health history must include these drugs 8. Discussion with clients and other professionals: Knowledge required of drugs using *proper terminology *adverse reactions *Pharmacist, Dentist, Client, Physician, Specialist What are the risks in treating this client??? Pharmacology involves lifelong learning Drugs are constantly changing  Pharmacology and Oral Health Care Provider Roles Obtain a health history Administer drugs in the office Handle emergency situations Plan appointments Discuss nonprescription medication Discuss nutritional or herbal supplements Discuss drugs and interactions  Sources of Information Mosby or Lippincott, Williams, Wilkens Merck Physician’s desk reference www.mayoclinic.com www.fda.gov/medwatch - Must be current (1-2 years) – check publication date - Keep chair side/in office at least 1 reference text - Electronic resources - Need info. about OTC drugs and prescription drugs - Judge by lack of bias - Other sources - Pharmacist & computer software & Internet (must be reliable)  Physicians’ Desk Reference – Also referred to as the “PDR” – An updated source of information supplied by drug companies about their products – Available as a bound text or CD-ROM  Package Inserts – Information sheet describing the drug for the patient Side effects Adverse or long-term effects Precautions Contraindications Dosage and route  Drug Names All drugs have at least 2 names - sometimes more 1. chemical - when drug is being investigated - determined by its chemical structure - “code name” - example RU-468 or lidocaine (2-diethylamino-2-6 acetorylate) 2. generic - name before marketing (only 1) - official name (ibuprofen & lidocaine) - small letters & only one name - regulatory agencies determine name  (Drug names continued) 3. Trade/Brand Name - this is the marketing name (more than 1) - often the company name - it is Capitalized - Motrin, Advil, Xylocaine  Trade/Brand vs. Generic Valium diazepam Aspirin acetacylic acid Xylocaine lidocaine Tylenol acetaminophen *It is important to know the generic name in cases of allergies *Generic name is older *Trade name is newer *Some drugs are difficult to discuss as may have many ingredients -Multiple-entity drugs  Drug Substitution Drugs can be judged “similar” in several ways: Chemically equivalent – Two formulations of a drug meet the chemical and physical standards established by regulatory agencies Biologically equivalent – Two formulations of a drug produce similar concentrations of the drug in blood and tissues Therapeutically equivalent – Two formulations of a drug have an equal therapeutic effect  Generic Equivalence After 17 years the patent of the original drug expires – Other companies can market same compound under a generic name Drug meets standards set by regulatory body & is chemically equivalent EXAMPLE- Life brand acetaminophen =Tylenol Difference: THE PRICE $$$$$$ The 2 drugs produce the same effect, have the same % in body tissues & are biologically the same Generically equivalent drugs can be substituted for each other  Drug Index Good reference for dental hygienist to refer to Many client’s don’t remember names and spelling of drugs they take Found in page 321 (back of textbook) List is always changing  DRUG LEGISLATION Food & Drug Act (FDA) 1906 – protects public from risks in sale & drug manufacturer by ensuring they are both safe and effective – grants approval for drugs to be marketed Harrison Narcotic Act 1914 – established regulations for opium, opiates & cocaine – Marijuana Laws added in 1937 Controlled Substance Act 1970 (replaced Harrison Narcotic Act and Drug Abuse Control Amendments) – established requirements for control & safe keeping of narcotics (Demerol, codeine) – Sets current requirements for writing prescriptions Omnibus Budget Reconciliation Act 1990 – Pharmacists must provide patients with counseling and a prospective drug utilization review (DUR)for Medicaid patients – Although this law only mandates Medicaid patients Pharmacy Boards interpret this to cover all patients  Canadian drugs are controlled @ the federal level Health protection branch is responsible for monitoring safety or adverse reactions Provincial government does not directly regulate the sale or manufacture of drugs Process of New Drug Development  Clinical Evaluation of a New Drug Testing has 4 Stages - 12 years and over 350 million dollars from time drug is synthesized to availability 1. Preclinical Stage -Testing or Toxicity Tests - done on animals -takes 3 years - look for carcinogenicity & tetragenicity - How is drug broken down or eliminated from the body? 2. Clinical Stage-Trials on Human - Prior to this stage the drug must be submitted for Investigational New Drug (IND) approval before moving to clinical trials - 3 Phases in this stage: Phase 1- small and then increasing doses on limited # of subjects, tests safety, drug toxic effects, dose range Phase 2- larger # of subjects, tests dose range & effectiveness - Adverse reactions reported to FDA Phase 3- large # of subjects, tests safety, dose & efficacy 3. NDA Review -In this stage the drug must be submitted for New Drug Application (NDA) approval before moving to Postmarketing Surveillance 4. Postmarketing Surveillance Phase 4 -drug is released and marketed under supervision -toxicity of the drug is recorded and can be removed from the market if considered serious *If drug is approved then there is unlimited marketing  Role of R.D.H. in Rx Writing 1. Check for errors 2. Answer the client’s ???? 3. Give client instructions: dose, how long to take, when, why?, side effects & interactions – have client repeat 4. Chart everything 5. Watch for drug shoppers 6. Safeguard Rx pads 7. Safeguard Rx drugs 8. Scope of practice – may Rx depending on province/state  Classical Format for Prescriptions 1.Superscription - client information & Rx symbol – “take thou of” 2.Inscription - drug name, form & amount 3.Subscription - directions to pharmacist 4.Transcription/Signature - directions to client Modern Format for Rx Writing 1. Heading - contains Name, address, phone # of the DDS./DR. - name, address, phone #, age of the client - date of the Rx 2. Body - contains Rx (take thou of) symbol - name & dosage of the drug - amt. to be dispensed - directions to the client ( sig.) - example page 8 3. Closing - prescriber’s signature - drug enforcement # - refill instructions  A typical prescription…. 1. Heading 2, 3 & 4 Body Remainder is closing Signatura (Sig) includes information on how much drug to take, how to take it, and how often to take it. Prescription Writing  Prescription Label Regulation The law requires that all prescriptions be labelled with the following: Also included: – Pharmacy’s name, address, phone number – Patient’s and Dentist’s names – Directions for use – Name of the medication and strength – Original date and refill date – Quantity dispensed – Number of refills remaining – Generic name must be accompanied by the manufacturer – Trade name does not need manufacturer  Prescription Label Figure 01-04. Sample of a typical prescription label.  Electronic and Fax Prescribing Allowed in many provinces Prevents errors and also client tampering Record kept in client’s chart  Common abbreviations (Table 1.3) Complete Activity Sheet Canadian Classification of Drugs and Drug Scheduling A drug schedule is a method of classification that places drugs in certain categories according to various characteristics. Ontario adopts the National Drug Scheduling System model developed by the National Association of Pharmacy Regulatory Authorities (NAPRA) as the provincial model. This scheduling system uses three schedules or four categories of drugs that Ontario uses. Schedule 1 Drugs: – These drugs require a prescription. In Ontario, chlorhexidine gluconate is the only schedule 1 drug that dental hygienists are able to prescribe, dispense or sell. – However, dental hygienists may buy and use other schedule 1 drugs while providing therapeutic services to clients. – For example, minocycline hydrochloride (Arestin®), and doxycycline hyclate gel (Atridox®) are schedule 1 drugs typically used by dental hygienists in conjunction with scaling and root planing to treat chronic periodontitis.  Canadian Classification of Drugs and Drug Scheduling Schedule 2 Drugs: – These drugs do not require a prescription. – However, they do require professional intervention with an appropriately qualified health care professional. – These items must be sold from an area where the public cannot access them and there is no opportunity for client self-selection. – An example of a schedule 2 drug that is purchased in dental hygiene practice is nitroglycerin (typically found in the medical emergency kit). Schedule 3 Drugs: – These drugs are suitable for client self-selection but may pose risks for certain groups of people and should be sold where an appropriately qualified health care professional is available to provide advice when required. – For example, fluorides used for the prevention of dental caries, contain 1 mg or less of the fluoride ion per dosage unit and therefore do not require a prescription, but clients can only buy them from pharmacies. A treatment dose (a thin ribbon) of PreviDent® 5000 Dry Mouth (Rx) contains approximately 2.5 mg fluoride Canadian Classification of Drugs and Drug Scheduling Unscheduled Drugs: – These drugs can be sold without professional intervention. – The labelling of these drugs is considered to be sufficient enough to ensure that the client will make a safe and effective choice and will use the drug according to its directions. – These drugs are not included in schedules 1, 2 or 3 and may be sold from any retail outlet. – Examples of unscheduled drugs recommended by dental hygienists are acetaminophen, ibuprofen, and aspirin.  US Scheduled Drugs from Text Not relevant in Canada These are controlled substances divided into 5 schedules according to abuse potential US Requirements for Rx Controlled Drugs 1. DEA # needed (Drug enforcement administration) 2. Schedule II – IV drugs require a Rx 3. Dental Hygienist may write but the Dentist must sign 4. Schedule II drug cannot be phoned in unless Rx follows within 72 hrs (written in ink) 5. Cannot be refilled if schedule II drug 6. Different rules in different countries (triplicate forms)  Recommending, Prescribing and Using Prescribing is a privilege available to dental hygienists who have demonstrated the appropriate skill, knowledge and judgment by successfully passing the Drugs in Dental Hygiene Practice Examination (DDHPE). Principles must be followed by dental hygienists when issuing a prescription to ensure that a client is given a safe and effective drug regimen. Recommending and using drugs must follow the same principles as prescribing even though issuing a prescription is not a requirement for a schedule 2, 3 and unscheduled drug. Patient of record refers to the person for whom the Rx is written Expectations before prescribing, when prescribing and after prescribing Before Prescribing: Ensure that prescriptions are only issued for individuals with whom you have a dental hygienist-client relationship -Client of record Only prescribe drugs for the purposes of treating a client’s oral condition. Review the health history including the drugs the client is currently taking. Consideration must be given to the most appropriate drug in treating the current condition to achieve optimum oral health. Consideration must be given to potential interactions between current medications and the drug that is being prescribed.  Expectations before prescribing, when prescribing and after prescribing When Prescribing: Written, verbal and faxed Use a handwritten or typed prescription on a formal prescription template to reduce the chance of misinterpretation associated with verbal or faxed transmissions.  Verbal prescriptions should be used in urgent situations only.  Faxing should be used with caution: -some pharmacies may not accept -transmissions may be subject to random marks (fax noise) leading to misinterpretations -a follow-up may be needed for clarification or verification purposes; -a prescription must only be faxed to a single pharmacy.  Expectations before prescribing, when prescribing and after prescribing When Prescribing: Written, verbal and faxed Prescriptions must be understandable, legible, and contain the following information:  the name and address of the person for whom the drug is prescribed  the name, strength (where applicable) and quantity of the drug that is prescribed  the directions for use  the member’s name, address, telephone number, title and registration number issued by the College the member’s signature the date on which the drug is prescribed the number of refills, if applicable  Expectations before prescribing, when prescribing and after prescribing When Prescribing: Prescribing is limited to chlorhexidine and its salts. Fluoride (topical and systemic delivery) used for caries prevention does not require a prescription because it contains less than 1 mg of fluoride ion per dosage unit and falls under schedule 3 of the National Drug Scheduling System. Drugs purchased from a pharmacy for use in a dental hygiene practice should have a clear notation on a prescription that it is “FOR IN OFFICE USE”. An accurate copy of the information recorded on the client’s prescription must be recorded in the client’s health record. Photocopies and carbon copies are acceptable and convenient.  Expectations before prescribing, when prescribing and after prescribing After Prescribing: Educate clients about why the drug was prescribed, how the drug works, how and when to take it including missed doses, and any possible side effects. Ensure that client’s right to choose a pharmacy is respected and take any steps necessary to help accommodate this. Respond in a timely matter when contacted by a healthcare provider for purposes of verifying a prescription or questions about the drug prescribed. Ensure that an on-going evaluation of the client’s response to the prescribed drug(s) allows for a timely refill, modification or discontinuation of the prescription as required. Report any adverse reactions regardless of severity to Health Canada ‒ MedEffect Canada (This information can be found on the Relevant Links and Telephone Numbers section of this document.)  Black Box Warning Purpose: To draw attention to safety concerns associated with the drug Educates both prescriber and patient about serious safety concerns associated with the drug  Orphan Drugs Drugs developed to treat rare medical conditions Treat diseases that occur in less than 200,000 people  Labeled and Off-Label Uses Labeled use indicates that the FDA has approved the drug for specific use Off-label use is use outside the stated FDA indications Diabetes medication Ozempic taken as a weight loss aid  Drug Recall Medications are taken off the market if there is a reasonable probability that use will result in serious adverse health consequences or death – Blood pressure medication Quinapril was voluntarily recalled recently over concerns it could increase the risk of cancer.  Skills Assessment 1. Define pharmacology 2. Why does an oral health care provider need this knowledge? 3. Explain the importance of health/medication histories. 4. Why should a dental practice keep more than 1 type of drug reference book 5. Define and give an example of: a) Chemical name b) Generic Name c) Trade Name d) Brand Name  Case Study The client is a 36-year-old female with a periodontal abscess associated with a 6-mm pocket on the mesiobuccal surface of tooth 4.7 (No. 30). After thorough periodontal debridement under local anesthesia, the client is given oral hygiene instructions for keeping the site clean. The client also is instructed to take ibuprofen 200 mg for pain as necessary and given prescriptions for penicillin 500 mg qid for 10 days and 0.12% chlorhexidine for rinsing bid. The client is scheduled to return in 10 days for evaluation. When the client returns, the site is still inflamed, and exudate is draining from the periodontal pocket. On questioning the client states, “My gum looked so sore that I was afraid to touch it, but the medicine made it feel better after about 3 days, so I didn't think that I needed it anymore. Besides, it was giving me an upset stomach, so I figured that it was all right to stop taking it. The mouthwash left an aftertaste, which didn't help my upset stomach, so I rinsed my mouth out with water, but it made it taste even worse. I used it though, every day.” Furthermore, the client took the ibuprofen twice on the day of the procedure only, then stopped, as she reported no addition. (Darby, Michele Leonardi. Dental Hygiene: Theory and Practice, 3rd Edition. W.B. Saunders Company, 032009. 12.2.2.8.2).  Case Analysis Assessment of the client's compliance suggests that she did not understand the need for the antibiotic or what to expect while taking this medication. The client should have been informed about: (1) the gastrointestinal upset that commonly occurs with antibiotic use and how to manage this side effect (2) the importance of taking the antibiotic until it was gone to ensure that the infection was treated completely and to reduce the risk of bacterial resistance (3) This client demonstrated willingness to comply with the mouth rinse but should have been informed about taste alteration as a side effect. By rinsing with water after using the 0.12% chlorhexidine mouthwash, the client was rinsing away the flavoring agent and ended up tasting more of the medication that remained (4) Chlorhexidine will not resolve the remaining infection deep within the pocket. With the incomplete course of antibiotic therapy, the infection persists and now requires re-treatment. (Darby, Michele Leonardi. Dental Hygiene: Theory and Practice, 3rd Edition. W.B. Saunders Company, 032009. 12.2.2.8.2.1).