Pharmacology Revision PDF

**Pharmacology Revison** **DEFINE PRESCRIPTION AND DISCUSS PROFESSIONAL GUIDELINES SURROUNDING THE PRESCRIPTION OF POM-VPS MEDICATIONS (8)** Definition of prescription The action of assessing the animal's disease or condition and deciding on the most appropriate medicine to supply or administer...

**Pharmacology Revison** **DEFINE PRESCRIPTION AND DISCUSS PROFESSIONAL GUIDELINES SURROUNDING THE PRESCRIPTION OF POM-VPS MEDICATIONS (8)** Definition of prescription The action of assessing the animal's disease or condition and deciding on the most appropriate medicine to supply or administer (1). Suitable professional guidelines can include the following: Only a veterinary surgeon, pharmacist or SQP may prescribe a POM-V medicine (1). Many only be prescribed following a clinical assessment of the animal (1). The animal must be under that veterinary surgeon's care (1). Veterinary surgeon is personally accountable for their professional practice (1). Veterinary surgeon must always be prepared to justify their decisions and actions (1). Ensure a range of reasonable treatment options are offered and explained (1). Make decision of treatment based upon animal health but also needs and circumstances of the client (1). Obtain the client's consent to treatment unless delay would adversely affect the animal's welfare (1). **WITH REFERENCE TO THE BVA GUIDELINES, CONSIDER THREE ACTIONS WHICH ENCOURAGE SUSTAINABLE USE OF ANTIMICROBIALS (6)** ** Work with clients to avoid the need for antimicrobials (1), through the use of an integrated disease control programme or the isolation of infected animals where possible (1).** ** Avoid inappropriate use (1), advise clients on correct administration of products and completion of course or avoid under-dosing (1).** Choose the right drug for the right bug (1), identify likely target organisms and predict their susceptibility or create practice-based protocols for common infections based on clinical judgement and up to date knowledge or use antimicrobials with a spectrum as narrow as possible (1). Monitor antimicrobial sensitivity (1), determine microbiological sensitivity where possible to encourage correct treatment can be implemented (1). Minimise prophylactic use (1), use only when animals are at risk and evidence identifies a reduction in morbidity or regular assessment of prophylactic use and development of written protocols for when prophylactic medication is appropriate (1). Minimise use perioperatively (1), use only when necessary and supported by strict aseptic techniques (1). Record and justify deviations from protocols (1), keep accurate records of treatment and outcome to help evaluate therapeutic regimes (1). ** Report suspected treatment failure (1), report through Suspected Adverse Reaction Surveillance Scheme (1).** **CRITIQUE THE METHODS OF ENVIRONMENTAL MANAGEMENT IN THE PHARMACY AND JUSTIFY THE USE IN STORAGE OF CYTOTOXIC MEDICATION (10)** Temperature: refrigerated (2-8oC) to avoid denaturing of cytotoxic drug (1). Maximum and minimum temperature recording to ensure temperatures remains within the required range (1). Separate fridge to avoid inappropriate use (1) Light: light sensitive drugs should be kept away from direct light (1). Use of light proof containers (1). Humidity: some drugs can absorb moisture from the atmosphere (1). Prevent by keeping in sealed boxes or the use of desiccant sachets prior to dispensing (1). Dry: evaporation of liquid drugs in dry conditions (1). Prevent through correct storage of medications with airtight containers (1). Stored away from client access (1). Labelled as cytotoxic to avoid inappropriate use (1). Clear designation of PPE (1). Kept in a clean environment to ensure good reach clients in a good condition (1). **DISCUSS THE PRINCIPLES OF PHARMACODYNAMICS WITH RELATION TO RECEPTOR RESPONSE (8)** The effect the drug has on the body (1) Full agonist (1): Able to activate the receptor/maximal biological response (1) Partial agonist (1): Do not activate receptors fully (1) Causes a partial response compared to that of a biological response (1) Antagonist (1): Binds to receptors but does not activate a response (1) **DISCUSS THE ROLE OF THE VETERINARY NURSE WHEN REPORTING ADVERSE REACTIONS (12)** In the UK anyone can report adverse effects (1) It is not a legal obligation but the RCVS Code of Professional Conduct states that VNs should report adverse events (1) Need to be able to recognise adverse reactions and can categorise them according to: Augmented (1): enhanced drug reaction (1) Bizarre (1): allergic reactions (1) Chronic (1): continuous therapy (1) Delayed (1): a long term after treatment (1) End of treatment withdrawal (1): if stopped suddenly (1) **DESCRIBE THE IMPACT OF POOR HEPATIC AND RENAL FUNCTION TO THE EXCRETION OF MEDICATIONS DURING PHARMACOKINETICS (6)** Renal elimination = regulated by glomerular filtration rate (1). If blood flow to the kidney is poor = decreased elimination (1) = toxicity (1). Hepatic elimination = regulated by functional hepatocytes (1). If liver disease is present = decreased elimination (1) = toxicity (1). **EVALUATE THE ROLE AND PROFESSIONAL RESPONSIBILITIES OF THE VETERINARY NURSE IN THE INTERPRETATION OF PRESCRIPTIONS AND CARE PLANS TO SUPPORT CLIENT CONCORDANCE FOR THE LONG-TERM TREATMENT OF A PATIENT SUFFERING WITH DIABETES MELLTIUS (100).** Introduction of client concordance: an agreement between a veterinary team and their client in relation to treatment. Introduction of key terminology including description of aetiology, clinical signs and disease status of patient. Reference to long-term treatment: Insulin treatment: twice daily injections. There are two licensed insulin products for use in cats (Caninsulin and ProZinc). Need for administration via specific calibrated syringes. Option to administer Caninsulin via Vetpen to add owner administration. Reference to varying response to insulin treatment in cats and need for glucose monitoring to determine required dose. Reference made to safe administration and handling guidelines. Helps the client accurately measure the amount of insulin required. Use calibrated syringes ONLY -- and note may be specific to the insulin type. Duration of action: approx. 12 hours with peak action at approx. 6 hours.  Varies according to insulin resistance of individual. Consideration of stabilisation phase to encourage common expectations between owner and veterinary staff: Insulin therapy is initiated with the starting dose of 0.25 iu/kg (dogs) 0.5 IU/kg (cats) twice. BG curve after 10-14 days; dose adjustments to establish maintenance dose should be made by increasing or decreasing the daily dose by approx. 10% (dogs), 0.5 IU at a time (cats). Duration of action as determined by BG curve may require treatment to be administered twice daily. Dietary management: Synchronized feeding with the treatment and the daily ration divided into two meals. Low carbohydrate diet recommended. Reference made to methods to support client understanding of treatment. Agree expectations with owner. Demonstration of administration technique. Storage of insulin in the fridge and storage away from away from children and other pets to avoid them being accidentally eaten. Diabetic clinics with veterinary nurse. Regular weight checks. Follow up phone consultations to check process after diagnosis. Consider aspects of the Code of Professional Conduct and any responsibilities that the VN will have in this case. **Discuss the concept of bioavailability and identify two methods to improve the bioavailability of oral medications. 5** Bioavailability is the percentage of an administered dose of unchanged drug that reaches the systemic circulation. There are two types absolute and relative. Lipid Based carriers to increase absorption of a drug. **Prodrugs:** it is an inactive derivative of a drug that is metabolised in the body to release the active drug. **Discuss the use of withdrawal periods in the use of antibiotics in food production animals. 4** They refer to the designated time after an animal has been treated with antibiotics before the animal can be slaughtered, the use of this is in food safety as there will be residue of antibiotics potentially causing allergic reactions and antibiotic resistance if consumed. Withdrawal periods provide a necessary recovery time for animals to ensure they can heal from infections without the inhibition of their immune response by antibiotics promoting welfare. **Discuss methods of safe and appropriate storage for medications containing hormones. 8** these drugs can cause miscarriages and can cause changes in the human menstrual cycle as well as affect the respiratory and cardiovascular systems so it important to properly store them and put measures in place for people who are pregnant of serve RR AND C complications not to handle to drug. Safe and appropriate storage: 1. Temperature Control: need to be stored in a fridge at 2°C to 8°C and not frozen as this can alter they're chemical structures and effectiveness using thermoneters. 2. Light Protection: Avoid from direct sunlight and store in Opaque Containers. 3. Humidity Control: stored in a dry environment. High humidity can lead to the degradation of hormonal medications.  4. Clear labelling and stock control. 5. Keep away from children, other pets and pregnant women in a locked cupboard. 6. Safe disposal of drug following local regulations depending on schedule of drug. **With reference to the Greener Veterinary Practice guidelines, consider three actions which encourage sustainable use of parasiticides. 6** The Greener Veterinary Practice guidelines aim to promote sustainable practices in veterinary medicine, here are three actions which encourages sustainable use of parasiticides: 1. Integrate Parasite control programs: **Pharmaceuticals, Dietary supplements, Parasite monitoring, Environmental modifications and improvement of animal husbandry.** 2. **Minimise Waste and Improve Efficiency: improve storage and disposal, precision dosing and measuring equipment, system for tracking medication usage.** 3. **Right Product at the Right Time: consider parasite life cycle, Rotate anthelmintics, monitor for resistance against drug.** **Discuss the storage and record requirements for Schedule 3 drugs (5)** 1. Be kept in a secure space like a cabinet or fridge which is locked. 2. appropriate temperature, humidity and light conditions for the specific medication. 3. store Schedule 3 drugs separately from non-controlled medications and other controlled substances to reduce the risk of accidental misuse or cross-contamination. 4. Inventory records, the name, quantity, used and remaining. 5. Patient name and identification. Prescriber information Dosage , and quantity of the drug dispensed. Date of dispensing, Any specific instructions for use. 6. Training of handling the drug. 7. Regular audits should be conducted to ensure compliance with storage and record-keeping practices. **A) Using a specific example, discuss the principles of pharmacokinetics 6** **Absorption: Buprenorphine can be administered intravenously, it has a bioavabirlty of 30-40%.the drug is absorbed into the bloodstream from the site of administration.** Distribution:About 96% of buprenorphine is bound to plasma proteins in order to reach it's target organ. bound drugs = encourages slow release = influences the biological half-life. diffuse through extracellular fluid. Metabolism: in the liver 1.Phase 1 metabolism -- enzymes act on the drug through hydrolysis reduction or oxidation = metabolites. Phase 2 metabolism -- the metabolites are combined with a hydrophilic molecule through conjugation. Excretion: The drug is then eliminated in the ring via kidneys, faces etc. 1.Elimination rate = the rate at which the drug is eliminated from the body. Measured in mg/h. 2.Elimination half life = the time required for the concentration of a drug in the blood to decrease by 50% by metabolism and elimination. **B) For the same drug identify two drug interactions** 1. **CNS Depressants** 2. **CYP3A4 Inhibitors** **Critique the use of AVM-GSL medication and POM-V medication in relation to parasite control. 10** AVM-GSL: 1. **Accessibility** - Pros: can be purchased without a prescription, making them readily accessible to pet owners. This can increase treatment time for parasites. Cons: The ease of access may lead to inappropriate use, over-reliance, or misuse, resulting in incorrect treatment and contributing to drug resistance. 2. **Efficiency** **Pros:** effective against common parasites and can help control infestations quickly. **Cons:** have limited efficacy against certain resistant strains of parasites, particularly if not used according to veterinary guidance. 3. **Safety Profile.** 4. **Pros:** AVM-GSL products are generally considered safe for use in target animals. **Cons:** Without veterinary supervision, there might be instances of adverse effects or drug interactions being overlooked by the user. **POM-V Medications** **Targeted Treatment:** - **Pros:**  prescribe the most appropriate medication based on diagnostic tests, ensuring that the right drug is used for the specific parasite and its life stage. - **Cons:** The necessity of a veterinary visit can lead to potential under-treatment if there are accessibility or financial issues. **Professional Supervision:** - **Pros:** POM-V medications require a prescription from a licensed veterinarian, ensuring that medication use is based on professional assessment and diagnosis. - **Cons:** This can lead to delays in treatment, particularly in cases where rapid intervention is necessary, especially in large-scale farming. **Resistance Management:** - **Pros:** allow Structured approach to managing parasite resistance through tailored treatment plans and possibly incorporating preventive measures. - **Cons:** There may still be a potential for resistance development if treatments are not adhered to guidelines and if treatment is consistently based on the same classes of drugs without rotation or integration of non-chemical controls. **Discuss two legal requirements to be included on a label for a prescribed medication. 4** **Storage and Handling Instructions** - Recommended temperature (e.g., store at room temperature, refrigerate) - Protection from light or humidity - Expiry date or beyond-use date - Instructions regarding how to properly dispose of the medication once it is no longer needed or past its expiration. **Patient Information and Instructions for Use** - The name of the medication - Indications for use - Dosage instructions - Administration route - Important cautions and warnings **Discuss the processes associated with down and up regulation in the use of agonist drugs and how these impact therapeutic responses. 8** **Downregulation: Definition and Process** - **It o**ccurs when cells reduce the number of receptors available on their surfaces in response to prolonged stimulation by agonist drugs. - This can happen through mechanisms like receptor internalization and degradation, leading to decreased receptor sensitivity. **Impact on Therapeutic Responses:** - **Reduced Efficacy:** As receptors are downregulated, the therapeutic effect of the agonist diminishes, necessitating higher doses for the same effect (tolerance). - **Tolerance Development:** Chronic use of agonists can lead to patients needing increasingly higher doses to achieve desired effects, complicating treatment and heightening risks of side effects. - **Withdrawal Symptoms:** If an agonist is abruptly stopped after long-term use, withdrawal symptoms may arise due to the decreased availability of receptors for endogenous ligands. **Upregulation: Definition and Process** - **Upregulation** occurs when cells increase the number of receptors on their surfaces in response to the absence or blockage of agonists, often as a compensatory mechanism. - This process can involve increased receptor synthesis or reduced degradation, leading to heightened sensitivity to agonists. **Impact on Therapeutic Responses:** - **Increased Sensitivity:** Following prolonged absence of an agonist or exposure to an antagonist, re-exposure to the agonist may elicit a stronger response due to the increased receptor density. - **Rebound Effects:** Stopping an antagonist may lead to an exaggerated response (rebound effect) when the agonist is reintroduced, potentially complicating treatment management. - **Potential for Enhanced Side Effects:** Increased receptor numbers can also elevate the risk of side effects when agonist therapy is resumed. **--Review current legislation related to pharmacology.** **Evaluate the role and professional responsibilities of the veterinary nurse in the safe and effective administration palliative chemotherapy, in the treatment of a canine patient recovering from limb amputation due to osteosarcoma.**