Drug Interactions PDF

Drug Interactions Assist.Prof.Dr. Nevzat Birand- [email protected] Drug Interactions Medicines help us feel better and stay healthy. But sometimes drug interactions can cause problems.  HOW DOES DRUG INTERACTION OCCUR??? **An interaction can occur when the effects of one drug are c...

Drug Interactions Assist.Prof.Dr. Nevzat Birand- [email protected] Drug Interactions Medicines help us feel better and stay healthy. But sometimes drug interactions can cause problems.  HOW DOES DRUG INTERACTION OCCUR??? **An interaction can occur when the effects of one drug are changed by the presence of other drugs, herbs, food, drink. **Drug interaction is defined as the pharmacological activity of one drug is altered by the concomitant use of another drug or by the presence of some other substance.  HOW DOES DRUG INTERACTION OCCUR??? ***Drug interactions occur when patients frequently take more than one drug. They may take multiple drugs because of ✓ a single disorder ✓ multiple disorders ✓ OTC (Over The Counter) They may take caffein, nicotine, alcohol, herbal medicine and drugs concurrently. Factors contributing to drug interactions; Multiple drug therapy (Polypharmacy) Multiple prescribers. Multiple pharmacological effects of the drug. Multiple diseases (Hepatic diseases, Renal diseases) Poor patient compliance. Advancing the age of the patient. Drug-related factors. There are three types of drug interactions. (1)Drug-Drug Interactions (2)Drug-Food Interactions (3)Drug-Diseases Interactions (1)Drug-Drug Interactions Drug-drug interactions occur when two or more drugs react with each other. It’s the most common type of interactions. This drug-drug interaction may cause minor or severe or unexpected side effects. For example, If a patient takes pain-killer medication and antihistamine medication, at the same time, the patient can observe more drowsiness effects due to the drugs' side effects. (2)Drug-food interactions Food can cause clinically important changes in drug absorption which can happen in the Gastrointestinal (GI). Therefore, certain drugs should not be taken with certain food. Food frequently decreases the rate of drug absorption. (2)Drug-food interactions Medications can interact with foods. For example, Grapefruit juice Kiwi Pomegranate Green tea Sage tea Milk products Alcohol EX: Tetracycline is an oral antibiotic in the tetracyclines family of medications. Calcium containing foods (milk, cheese and other dairy foods) Calcium is Insoluble and Unabsorpable complex Tetracycline+Calcium Impact: Absorption reduce and Antibacterial effects may be lost. EX: Grapefruit juice is an inhibitor of CYP3A4 in the liver and intestinal wall. Grapefruit juice can inhibit the metabolism of certain drugs, thereby raising blood levels. Grapefruit juice can increase the blood levels of atorvastatin. EX:Food may also (rarely) have direct impact on drug action Foods rich in Vitamin K (broccoli, Brussels sprouts, cabbage) can reduce the effects of warfarin. Vitamin K may reduce the effectiveness of warfarin. warfarin acts by inhibiting Vitamin K-dependent clotting factors. (3) Drug-Disease Interactions Drug interactions don’t always occur with just other drugs or foods. A medical condition can impact the way a drug works. For example; Over-the-counter oral decongestants like pseudoephedrine may increase blood pressure and can be dangerous if patient have high blood pressure *** Drug interactions can cause increased costs in healthcare. *** A serious drug interaction could result in injury, hospitalisation, or rarely, death. ***Not all drug interactions are bad*** Mechanisms of Drug Interactions Drug interactions can be related to the following mechanisms: ✓ Pharmaceutical interactions ✓ Pharmacokinetic interactions ✓ Pharmacodynamic interactions ***An interaction occurs when pharmacokinetics or pharmacodynamics of drug are changed. ***Sometimes the drug interaction can be caused by more than one mechanism, although usually only one mechanism is more significant. Pharmaceutical interactions **Interactions that occur prior to systemic administration. For example: Incompatibility between two drugs mixed in an IV fluid. These interactions can be physical (e.g. with a visible precipitate) Pharmacokinetics Interactions Pharmacokinetics is ‘what the body does to the drug’. ✓ One drug alters the rate or extent of absorption, distribution, metabolism or excretion of another drug. ✓ A change in blood concentration causes a change in the drug’s effect (the so-called ADME interactions).  Alterations in absorption Drug absorption may be enhanced or reduced by drug interaction EX: Ketoconazole is an anti-fungal medication that is used to treat certain infections caused by fungus. Ketoconazole +Antacids Proton Pump Inhibitors H2 receptor blockers Impact: Antacids, Proton Pump Inhibitors and H2 receptor blockers can decrease the absorption and blood levels of ketoconazole and make the medication less effective against fungal infections. Therefore, these drugs must be separated by at least 2 hours at the time of administration of both. EX: A-Digoxin (AF, HF)- 40% or more of the administered dose is metabolised by the intestinal flora. B-Antibiotics kill a large number of the normal flora of the intestine Digoxin+Antibiotics Impact: Increase digoxin concentration and increase its toxicity. Pharmacodynamic Interactions Pharmacodynamic drug-drug interactions (DDIs) occur when the pharmacological effect of one drug is altered by that of another drug in a combination regimen. If drug A and drug B are both toxic to the same organ, taking them together will cause more injury than if they were not combined. Ex. Isoniazid and rifampin are hepatotoxic. Drug Interactions Categories Each Interact monograph is assigned a risk rating of A, B, C, D, or X. Or It is sometimes shown that Major, Moderate or Minor interaction. Drug Interactions Data have not demonstrated either pharmacodynamic or pharmacokinetic A No Interaction interactions between the specified agents Data demonstrate that the specified agents may interact with each other, but there is little to no evidence of clinical concern resulting from their B No action needed concomitant use. Data demonstrate that the specified agents may interact with each other in a clinically significant manner. The benefits of concomitant use of these two medications usually outweigh the risks. An appropriate C Monitor therapy monitoring plan should be implemented to identify potential negative effects. Dosage adjustments of one or both agents may be needed in a minority of patients. Data demonstrate that the two medications may interact with each other in a clinically significant manner. A patient- specific assessment must be conducted to determine whether the benefits of concomitant therapy outweigh the risks. D Specific actions must be taken in order to realize the benefits and/or minimize the toxicity resulting from concomitant Modify regimen use of the agents. These actions may include aggressive monitoring, empiric dosage changes, choosing alternative agents Avoid Data demonstrate that the specified agents may interact with each other in a clinically significant x combination manner. The risks associated with concomitant use of these agents usually outweigh the benefits. These agents are generally considered contraindicated. Drug Interactions Drug Interactions ***alprazolam: management of anxiety disorders, specifically panic disorder or generalised anxiety disorder ***Ramipril:Anti-hypertension Drug Interactions Drug Interactions Drug Interactions Drug Interactions Drug Interactions ***This is for Turkish Students ***This is for Turkish Students Drug Interactions- Practice Course Drug Interactions- Practice Course Drug Interactions- Practice Course Drug Interactions- Practice Course Drug Interactions- Practice Course  Community Pharmacy Design- Patient Counselling Assist. Prof. Dr. Nevzat Birand  How to be a Good Community Pharmacy!!!!! The American Association of Colleges of Pharmacy AACP recommends that consumers OR patients choose a pharmacy at which they can have a consulting relationship with the pharmacist. Being timely includes both processing the request quickly and having drug stock available to fill the prescription. Some patients need medications delivered to their home, and maybe they select a pharmacy which offers that service.  How to be a Good Community Pharmacy!!!!! A community pharmacy might offer healthcare services like Vaccination; Smoking cessation; Measurement of blood pressure, glucose, weight, Chronic disease management; Up-to-date technology at a pharmacy can assist a patient with prescription reminders and alerts about potential drug interactions, and so reducing medical errors. Community Pharmacy Services aim to achieve the ‘triple aim’: Better quality of care Better health outcome Lower costs Core Community pharmacy services are: Dispensing; Compounding; Emergency care (emergency contraception) and minor disease management. Medication management (unit dose packaging, new medicines service, medicines use review);  Community Pharmacy Layout Design "Layout primarily refers to the floor plan and the arrangement of equipment in front of you, which reflects how you want to flow your space and present your products". Community pharmacy layout can have an impact on your customer or patients experience, for better or for worse. ***The factors on which the success of community pharmacy depends are: Location Physical Environment Sufficient Finance Staff experience, and behaviour **Before designing a layout one must consider the following: Objective of the design Type of community pharmacy (Local, chain, independent pharmacies) Type of layout design Ideal Community Pharmacy Layout Design Chair Chair Pharmacy Layout is much more essential than pharmacy design. The prescription or dispensing area generally requires more lighting than the sales area (OTC drugs section). Most non-selling areas such as the walls and floors should be a neutral color. Lighter colours make the pharmacy appear more spacious, and the colourful merchandise becomes the attention getter. Avoid Retail Pharmacy Layout Designs on the floor covering that cause the space to look smaller and attract attention!!!!!!!!!! Dispensing Area. The dispensing area should have sufficient work bench space and shelving. The area should not be crowded so that staff can move around easily. Workflow is an important component in the dispensing area.  Dispensary area - Dispensary area should be wide and designed to support communication between the pharmacist and the patient. - There should be space to give advice and counselling to the patient in privacy. Dispensing prescriptions Dispensing prescriptions Reading and checking of prescription Pharmacy staff should check patients’ prescriptions. Patient’s name and address Age of patient if under 12 years Name, dose and quantity of medicine Date Prescriber’s name and address Signature of prescriber PATIENT COUNSELING Patient counseling is defined as a face-to-face, interactive meeting designed to change patient knowledge or behavior. It also refers to the process by which the pharmacist listens to his patients' concerns about medication and provides education appropriate to the patient's needs.  MEDICATION ERROR “Medication error is any preventable event that may cause or lead to inappropriate drug use or patient harm while in the control of healthcare professionals, patients, or consumers.” Medication errors can occur at many stages, from the point of prescribing the medication to the moment the medication is administered to the patient. Medication errors can be prevented.  MEDICATION ERROR What are the Causes of Medication Errors??? **Polypharmacy **Oral Prescriptions **Drug interactions **Communication problem **Similar drugs **Inappropriate drug selection **Sound-like drugs **Incomplete drug use **Busy working environment **Incorrect use of medication **Lack of computer support COMPLIANCE Compliance is defined as the degree to which the patient's behaviour conforms to the instructions of the healthcare providers. The benefits of patient compliance improve patient disease and clinical symptoms and reduce the cost of medical treatments.  REASONS FOR NON-COMPLIANCE Patient Factors; **Patients may not remember to take their medications. (elderly patients, psychological diseases, etc.) **Patients may discontinue or interrupt the drug due to early symptomatic relief (antibiotics, analgesics, etc.) **Asymptomatic disease (treatment delays) may be delayed in the treatment given. **Patients may not understand instructions. (geriatric patients, etc.) **Patients may not understand the importance of compliance with doses. REASONS FOR NON-COMPLIANCE Product factors; **Complexity of drug regimen (oral antineoplastics) **Inconsistency of dosage forms (Emend) **Unpleasant taste (enteral nutrition solutions) **Cost (chemotherapy drugs) **Side effects (chemotherapy drugs) **Potential for abuse (Opioids) REASONS FOR NON-COMPLIANCE Pharmacy Factors; **Lack of patient counselling **Not giving enough information about drugs **Lack of time **Staff shortage  THE PHARMACIST'S ROLE **Pharmacists can increase patient compliance with patient counselling. (With Pharmaceutical Care Programs) **Pharmacist is the best resource to provide Drug information. **Patient Counseling is one of the most important responsibilities of pharmacists. COMMUNICATION Communication Process Sender Message Channel Receiver Feedback Voice PATIENT COUNSELING *** During patient counselling, patients are asked by healthcare providers open-ended questions that help determine their knowledge about the disease and medications. SOOO WHAT SHOULD BE ASKED AND EXPLAINED TO THE PATIENT?  PATIENT COUNSELING **WHAT TO ASK AND WHAT TO SAY** **The brand name or generic name of the drugs used must be asked. **You should ask about the purpose of the use of previously used drugs. **The route of use, dosage form, dosage and application schedule of the drug should be checked. (including treatment period). **Do you have information about the precautions to be taken during the application? PATIENT COUNSELING **You should explain common side effects and How to manage them. **You should ask that ''Do you have knowledge of techniques for self- monitoring of drug therapy?'' (fasting blood sugar) **You should ask that ''Do you have have knowledge of appropriate storage conditions?'' **You should explain potential drug-drug or drug-food interactions or contraindications. PATIENT COUNSELING **You should ask that ''Do you have any Food Allergies or Drug Allergies?'' **You should ask that Pregnancy status (Does she want to have children now or in the future?) **You should ask that Alcohol use and smoking habits. HOW SHOULD EDUCATION BE GIVEN??? **One-to-One Education. -Face to face -Telephone **Written Education. - Email - Brochures - Reports - Newsletters  BARRIERS TO EFFECTIVE PATIENT COUNSELING Barriers to effective patient counselling include physical, psychological, administrative or time barriers. Such barriers make it difficult to establish effective communication. PHYSICAL BARRIERS ***Environmental barriers such as lack of privacy, which creates physical barriers between patients and doctors/pharmacists, can prevent effective communication. ***Environmental barriers are examples of physical barriers.  BARRIERS TO EFFECTIVE PATIENT COUNSELING PSYCHOLOGICAL BARRIERS Negative attitudes of physicians and pharmacists are often due to a lack of confidence or low self-confidence. Communication can be a problem for these people Physicians or Pharmacists should try to improve their communication skills through practice. A negative attitude is an example of a psychological barrier. BARRIERS TO EFFECTIVE PATIENT COUNSELING ADMINISTRATIVE BARRIERS The administrator thinks that the time that should be spent on communication can be made by looking after another patient. So this can be seen as a reason for communicating issues. BARRIERS TO EFFECTIVE PATIENT COUNSELING TIME BARRIERS Time barriers are linked to administrative barriers. Because the management is responsible for the number of personnel and the distribution of workloads. **Time is limited according to Pharmacists and patients. **Pharmacists say that they cannot spare time for patient counselling due to the high number of patients. On the other hand, patients say that they do not have enough time to receive patient counselling. BARRIERS TO EFFECTIVE PATIENT COUNSELING **Interpersonal communication is a fragile process. **Messages only help the patient when they are received and understood correctly. **If messages are incorrect, they may harm the patient and prevent a positive patient outcome. **It is important to understand these potential communication barriers so that a strategy can be developed to minimize or eliminate them. WAYS TO IMPROVE YOUR PATIENT COUNSELING SKILLS **Do not jump to conclusions or quick solutions without learning detailed information. **Do not move from one subject to another subject until each subject is completed. **Guide the interview using a combination of open-ended and closed-ended questions. **Keep your goals in mind clearly. WAYS TO IMPROVE YOUR PATIENT COUNSELING SKILLS Try to learn certain (basic) information about the patient Please use vary the techniques when interviewing and counselling a patient who is unable to read, has language proficiency, or has a visual or hearing impairment. Please take as much as brief note during counselling. This condition should not interrupt the communication with your patient.  WAYS TO IMPROVE YOUR PATIENT COUNSELING SKILLS Speaking and Listening techniques; You should stop speaking while the patient is speaking. You should get rid of distractions. You should make eye contact to show you're listening. Listen carefully to what the patient says. Get feedback to clarify the message. This shows that you are listening and trying to understand.  WAYS TO IMPROVE YOUR PATIENT COUNSELING SKILLS How to Become a Better Listener???? ***Take time to listen and give your full attention. ***Focus on your target. ***Ask questions. ***Get feedback. Give advice, but do not judge or blame the patient. PATIENT FOLLOW-UP FORM COMMUNICATION WITH PRIVATE PATIENTS GROUP Elderly Patients Patients with Psychological Disorder Pediatric Patients Patients with Disabilities  CONCLUSION The pharmacist must be aware of his role and responsibilities. Pharmacists are people who act logically to provide information. A Pharmaceutical Care Program is necessary for patients who have poor patient compliance. Thank you