VNSA7 Flashcards
Who are the VMD?
veterinary medicines directorate.
They control manufacture, authorisation, marketing, distribution and post authorised surveillance.
Assures safety, quality and efficacy of veterinary medicines.
To gain marketing authorisation what to companies have to prove?
-adherence to all regulations
-efficacy, quality and safety
-adherence to VMD codes of practice
Veterinary Medicines Regulations 2013 (VMR)
Regualtions and controls set by the VMD on veterinary medicines in the UK to ensure it is up to date and fit for purpose.
Controls manufacture, authorisation, marketing, distribution and post-authorised surveillance of VMP.
What information should be included on written prescriptions and drug labels.
NOAH compendium
The association representing the UK animal health industry.
Their aim = promote benefits of safe, effective, quality products and services for the health and welfare of animals.
Compendium of data sheets for animal medicines.
Available in website, app or book format
Animal Medicines Training Regulations Agency (AMTRA)
Regulatory body ensuring prescription and supply of veterinary medicines in the UK is undertaken responsibly by AMTRA qualified people.
Keep and maintain register of SQPs
Involved in the training, ethics and representation of SQPs
Veterinary prescribing cascade
Any medicine administered to an animal should be licensed or authorised for that species, condition or indication.
If not available, to avoid suffering the vet can use a cascade to treat.
‘Off label’ = using the medicine outside its purpose for use in which it has market authorisation for.
Veterinary prescribing cascade order
- A veterinary medicine authorised in the UK for use in another animal or the same animal but different condition.
- A medicine authorised in the UK for human use. (Import certificate with accordance by VMD)
- A medicine prepared on the spot by a vet, pharmacist or an appropriate manufacturers authorisation.
What is a generic product ?
A copy.
Can be used at the vet surgeons discretion, following the cascade. A human copy cannot be used if a veterinary version is available.
What should a vet surgeon do if the prescribing cascade is used?
Ensure all records of unauthorised and off label use of drugs are retained.
Inform the client of the cascade
Get written consent from client
Ensure they can administer the medications themselves or ensure it is done in accordance with their direction.
Storage of medicines
On delivery - store in accordance with manufacturer’s recommendations and keep records
Check in date and not damaged
Store out of direct sunlight
Dispensary shelves/cupboards = 8-15 degrees (not over 25)
Fridges = (2-8 degrees)
Locked controlled drugs in a secure and immobile cabinet with limited access.
Kept clean, dry and ventilated
Don’t allow general public access and dont eat and drink in the pharmacy
POM-V
Prescription only medicines
Prescription only medication
Dispensed only by a veterinary surgeon or written prescription
Clinical assessment performed first
Vet must be satisfied the person administering the drug is competent
POM-VPS
Prescription only medicines
Prescribed by a RQP
(Vet, pharmacist, SQP)
No clinical examination or assessment necessary
Drugs in this category often used as preventative treatment
Can be physical or written
NFA-VPS
Non food animal medicine
Prescribed by an RQP (vet, pharmacist, SQP)
No clinical exam required
Only used on non-food animals
(Panacur)
AVM-GSL
Authorised veterinary medicine, general sales list
No restrictions in sales - stocked in pet shops/supermarkets
Products in this category have a wide margin of safety
(Feliway)
Controlled drugs
Controlled under - The Misuse of Drugs Regulation 2001.
5 schedules - all different conditions of ordering, recording, delivery, usage and storage
POM-V
Schedule 1 drugs
These hallucinogenic drugs have no therapeutic use and vet practices are not authorised to possess them
Eg - ecstasy and cannabis
Schedule 2 drugs
Have to be requested in writing - must include:
The vets name and address
Intended purpose for the drug
The amount, form, strength required in words and numbers
The vets signature
Suppliers name and address and date of order
Must be stored in a locked immobile cabinet with limited access.
All movements of drugs, purchases and all individual supplies mist be recorded in the controlled drugs register within 24hrs.
Disposal must be denatured in the presence of someone appointed by the Home Office such as a policeman and signed in the controlled drugs register by both the witness and vet.
All invoices must be kept for 2 years although 5 is recommended
Eg - meth, ketamine, pethidine and fentanyl
Requisition required.
Prescription valid for 28 days - no repeat permitted.
Schedule 3 drugs
Must follow same regulations as schedule 2 however movement of the drugs is not required.
Eg - Buprenorphine, diethylpropion, temazepam, phenobarbital
Must be kept in a locked, secure cabinet
All involves kept for 2 years
Requisition required.
Prescription valid for 28 days - no repeat permitted.
Schedule 4 drugs
Split into 2 groups
Part 1 = benzodiazepines
Part 2 = anabolic and androgenic steroids
Invoices to be kept for 2 years
No Requisition required
Prescription valid for 28 days
Schedule 5 drugs
Drugs containing codeine and morphine in smaller amounts.
Written prescriptions are valid for 6 months.
Only requirement is to keep invoices for 2 years
What records need to be kept regarding pharmacy record keeping?
Any movement of POM-V and POM-VPS must be recorded.
Any damaged, returned or ood.
Controlled drugs
Kept for 5 years
Must include: date, incoming, outgoing, identity and quantity of drug, batch number, name and address of supplier or recipient, if dispensed to fulfil a written prescription keep the prescription.
Non food animals record keeping
Only need to record the batch number at the first time it is received or used, not at subsequent uses.
An annual audit is completed to ensure all drugs are accounted for.
Audit checked by VMD.
If a product is recalled the practice should be able to know where the product has gone. Any returned drugs should not be reused but disposed off.
Record keeping for food producing species
Apply to - vets, pharmacists, SQPs and the owner.
The vet must keep a record of the drug and any prescribed under the cascade.
Record must show: drug name, date of purchase, quantity purchased, withdrawal period.
When administered must show: their name and date, amount administered, identity of animal treated, name and address of supplier.
Records must be kept for 5 years
What is a withdrawal period?
Time taken for the administered drug levels to fall below maximum residue level.
Under EU law.
7 days for eggs and milk
28 days for mammal and poultry meat
Forbidden drugs = chloramphenicol, metronidazole, phenylbutazone
Horses are consider food producing animals unless stated otherwise.
What information is legally required to be on a written prescription?
-name, address, telephone number of the person prescribing the product
-qualifications of the person prescribing
-name and address of owner
-identification (name, breed, species)
-premises at which the animal is kept in if different to owners
-date
-signature or other authentication of the person prescribing
-name and amount of product prescribed
-necessary warnings
-withdrawal period if relevant
-the directions that the prescriber wishes to be on the product
-a declaration that the animal is under their care
-if it going to be under the cascade; a statement
-repeat instructions
Define proprietary
A name of a product or service registered by its owners as trademark and not useable by others without permission.
Define generic
Chemical name of a medicine
The drug is the same no matter how many companies make it.
Requirements for labelling medication
Must be indelibly and legibly written or printed. Pencil and non-water resistant ink is not acceptable.
Label should no obscure exp date
Every effort should be made to not obscure product information
Manufacture sheets passed onto client (The Veterinary Medicines Regulation 2005)
Recommend info on label = name and address of keeper and practice, date of dispensing, animal treatment only, animal name, drug name/dose/quantity, special precautions etc.
Define pharmacology
Study of how living organisms are affected by chemical agents
Define pharmacodynamics
The biochemical and physiological effect of the drug on the body
Define pharmacokinetics
ADME
The effect the body has on the drug (absorption, distribution, metabolism, excretion)
Define therapeutic index
This is an indicator of the safe effective dose of a drug vs its toxicity.
The margin of safety that exists between the dose of a drug that produces the desired effect and the dose that produces unwanted effects.
Define a side effect
A secondary effect - typically undesirable of a drug or medical treatment
An action of a drug other than for which it’s used. Seen at the prophylactic dose (eg- corticosteroids cause polyuria and polydipsia).
Define an adverse reaction
In pharmacology, any unwanted effect caused by the administration of a drug which may be known to occur regularly but not in all patients.
(Eg - metaclopramide occasionally causes animals to exhibit changes in mentation and behaviour, cats can appear disoriented and frenzied).
How can adverse reactions present ?
Localised or systemic
Transient or more persistent
Immediate or after long term administration
How are adverse reactions classified ?
Type A - augmented reactions = exaggeration of a drugs normal pharmacological action
Type B - bizarre reaction = unusual or unexpected reactions
Type C - continuing reaction = persist for a relatively long period of time
Type D - delayed = apparent sometime after using the medicine
Type E - end of use reaction = occur when treatment is stopped
Suspected Adverse Reactions Surveillance Scheme (SARSS)
Run by the VMD
Any unwanted or adverse reactions can be reported.
VMD can ensure any drugs issued with a Marketing Authorisation are effective and safe to use
Define contraindication
A condition that means a particular line of treatment is improper or undesirable
What can drugs do?
Mimic the physiological activity of the body’s own molecules
Block the physiological activity of the body’s own molecules
Some drugs produce their effects by combining with the cells receptors
Define affinity
Reflects the attractiveness of the drug to the receptor site, the ‘strength’ of the bond between a receptor and the drug.
Define specificity
The ability of the drug to combine with one particular type of receptor
Define efficacy
Inherent ability of the drug to induce a physiological response
Define potency
An expression of the activity of the drug in terms of the concentration or amount needed to produce a defined effort
Define potency
An expression of the activity of the drug in terms of the concentration or amount needed to produce a defined effect.
Define agonists
Combine with the receptors but don’t activate them. Causes the same action as the substance that normally binds to the receptor.
Define antagonists
Combines with receptors allowing for a partial response
What is bioavailability?
The proportion of the drug administered that reaches the systemic circulation
Define distribution
Distribution of the drug throughout the body’s tissues from the circulation is dependant on; properties of the drug and properties of the formulation.
Drug composition and hydration status affects absorption and distribution.
Movement of drugs happens from areas of high concentration to low (diffusion)
The blood brain barrier
The brain is particularly sensitive to toxins and has developed the barrier.
The brain has high energy levels and requires fats to supply this energy - lipids can readily cross the barrier.
CNS drugs are often lipophilic.
Drug uptake
Bound drug <—> free drug <—> drug in tissues
Opioid receptor activity
A full agonist binds to the receptor and activates it by changing its shape, including a full receptor response.
A partial agonist binds to the receptor and activates it with a small shape change in the receptor that induces a partial receptor response.
Drug elimination
Happens through:
Metabolism = converting drug to another form which will alter chemical properties.
Excretion = actual loss of drug from the body
Drug metabolism
First pass; pre-systemic metabolism = absorbed from gi tract it travels via portal circulation to liver before reaching systemic circulation.
Liver will extract and metabolise some drugs so well the amount reaching the systematic circulation is considerably less than the amount absorbed.
Meaning a much larger dose is required.
Eg - chlorpromazine, lignocaine, morphine and pethidine
Drug excretion
Actual loss of drug molecule from the body.
4 routes:
Kidney = most common. leaves via urine.
Biliary system = secreted into bile via the liver but are then reabsorbed from the intestine. Eliminated via faeces but quite minimal.
Gastrointestinal
Respiratory = the lungs - only with highly volatile or gaseous agents.
Define minimum effective concentration (MEC)
The lowest concentration level at which there is still therapeutic action
Define minimum effective concentration (MEC)
The lowest concentration level at which there is still therapeutic action
Define competitiveness
Most drugs temporarily bind with the receptor site
Increased concentrations lead to increased competitiveness
They’re reversible
Define downregulation
Reduced response to prolonged exposure to drug ‘resistance’
Define upregulation
Increased sensitivity to prolonged exposure to drug - increased receptor sites
Increased sensitivity to endogenous factors if stopped suddenly
(Steroids, beta blockers)
Define synergism
Increases action of 2 or more drugs
1 + 1 = 3
Define potentiation
The action of an ineffective drug enhances the action of another
0 + 1 = 2
Define antagonism
A drug inactivates the action of another
1 + 1 = 0
Define minimum inhibitory concentration (MIC)
A way to determine how sensitive bacteria are to the antibiotic
Low MIC = high sensitivity
Define minimum bactericidal concentration (MBC)
The lowest concentration of an antibacterial agent required to kill a particular bacterium
Antibiotic acronym
Prescribe only when necessary
Reduce prophylaxis
Offer other options
Treat effectively
Employ narrow spectrum
Cure appropriately
Tailor your practice policy
Monitor
Educate others
(Protect me)
Beta-Lactams drugs
Variable activity
Gram +ve and anaerobes
Bactericidal
Prevent cell wall synthesis
(Penicillins, cephalosporins, carbapenems, monobactams)
Aminoglycosides drugs
Bactericidal
Interfere with protein synthesis
Activity primarily gram-ve aerobes
(Gentamicin, neomycin)
Fluoroquinolones drugs
Broad spectrum of activity
Damage bacterial DNA
Bactericidal
Should not be used as a first line antibiotic
(Enrofloxacin, marbofloxacin)
Cardiovascular drugs
Act on the heart, blood vessels, kidneys or the blood clotting system. Many drugs have more than 1 indication.
Cardiac glycosides - slows the ventricular heart rate, has a mild positive inotropic effect, increases the force of contraction. Used in congestive heart failure, atrial fibrillation (eg digoxin)
Phosphodiesterase inhibitors - has a positive inotrope effect, causes vasodilation. Used in congestive heart failure (pimobendan)
Angiotensin converting enzyme (ACE) - reduce detrimental changes to the heart structure, produce vasodilation and reduces sodium and water retention. Used in congestive heath failure and reduction of proteinuria associated with chronic kidney disease in cats (eg, benazepril, ramipril)
Calcium channel blockers - reduce contractility of the heart, slows heart rate and dilates blood vessels. (Eg amlodipine, diltiazem)
Antiarrhythmics - controls abnormal cardiac rhythm (eg lidocaine)
Nitric oxide donors - dilates blood vessels. Used in emergency treatment of congestive heart failure. (Eg glycerol trinitrate)
Sympathomimetics - increases the force of the hearts contraction and dilating the mesenteric and renal vessels. Indicated in acute myocardial failure for positive inotropic support (eg, dobutamine)
Beta blockers - antiarrhythmic drug with a negative inotrope and chronotrope effect. Used in cats with hypertrophic cardiomyopathy, restrictive cardiomyopathy and patients with pressure overloaded ventricles and hyperthyroidism. (Propranolol)
Vasodilators - reduce the workload of the heart by reducing venous pressure
Loop diuretics
Eg - furosemide and torsemide
Work by inhibiting the re-absorption of chloride, sodium and water in the ascending loop of Henle.
Furosemide also decreases reabsorption of sodium and chloride in the distal renal tubule
Thiazide diuretics
Eg hydrochlorothiazide
Acts on the distal convoluted tubule, inhibiting reabsorption of sodium ions.
Result in moderate diuresis and natriuresis and are associated with potassium loss.
Not very effective in congestive heart failure.
Potassium sparing diuretics
Eg - spironolactone
Mild diuretics used in combination with other diuretics to reduce potassium loss.
Shouldn’t be used with ACE inhibitors
Cytotoxic and anti-neoplastic drugs
Anti-neoplastic - can be grouped by biochemical mechanism of action.
Alkylating agents (cyclophosphamide, chlorambucil, lomustine) break the DNA molecules and interfere with DNA replication so it cannot divide
Vinka alkaloids/mitotic spindle inhibtors (vincristine, vinblastine) binds to the cytoplasmic proteins and stop mitosis in metaphase
Antimetabolites (methotrexate, cytarabine) mimic substrates needed for nucleic acid synthesis, so lead to non-functional molecules
Antitumor antibiotics (doxorubicin, mitoxantrone, acitnomycin-D) bind to DNA, preventing RNA synthesis, and therefore essential proteins
Platinum compounds (carboplatin, cisplatin) work by binding together strands of DNA stopping cell replication
Glucocorticoids - cytolytic for lymphoid tissues, so useful in lymphoid malignancies
Corticosteroids
Prednisolone, methylprednisolone, dexamethasone, betamethasone, hydrocortisone
Used as; anti-inflammatory, anti-neoplastic and at high doses as immunosuppressive drugs.
Have both mineralocorticoid and glucocorticoid activity but to varying degrees.
Mineralocorticoid = controls the electrolyte (Na/K) and water balance and endogenous mineralocorticoid is aldosterone.
Glucocorticoid = affects metabolism, inflammatory and immune responses
NSAIDs
Carprofen, Meloxicam and ketoprofen
Management of short term or long term inflammatory conditions
They act by inhibiting the enzyme cyclo-oxygenase (COX), responsible for the production of prostaglandins.
These are end-product molecules of the metabolism of unsaturated fatty acids released by cells which have significant role in the inflammatory process, including causing pain by direct action upon nerve endings.
2 forms of COX enzyme:
COX-1 = pathway is necessary for normal physiological functions
COX-2 = involved in inflammatory pathways so inhibition results in antipyretic and anti-inflammatory actions
Antihistamines
Different classes of antihistamines
H1 antagonists = chlorphenamine and cetirizine
H2 antagonists = cimetidine
What 3 groups can nervous system agents be divided into?
Anti-epileptic
Sedatives and tranquillisers
Analgesics
Anti-epileptic drugs
Eg, Phenobarbital, potassium bromide, imepitoin, diazepam
These drugs reduce frequency of seizures, epilepsy is incurable.
Anti-epileptic drugs should not be stopped suddenly.
Sedatives and tranquillisers
Common in premeds in combination with an opioid analgesic.
Sedative = calms nervousness and excitement - makes patient sleepy.
Tranquillisers = calms or quiets an anxious patient (acepromazine, diazepam)
Opiate analgesics
Most are controlled drugs
Provides good sedation and analgesia
Can cause high heart and respiratory rates
What are the 2 forms of immunity?
Passive - via the transfer of maternal antibodies, via antiserum containing antibodies. Short lived immunity lasting 1-3mths.
Active - immune system stimulated by a challenge or an exposure to a pathogen. Exposed to an infection. Via a vaccine
What are the types of vaccines ?
Live - live organisms still capable of replication, but not disease
Dead or attenuated - inactivated organisms that no longer replicate. These normally require more than one dose to induce adequate immunity.
Multivalent vaccine - contains antigens to multiple diseases.
Adjuvant - this is added to the vaccine to increase the immune response induced.
Pharmacovigilance
For all authorised veterinary medicines there’s ongoing safety and efficacy monitoring.
Considers the science of adverse reactions and where the medicine has failed to work.
Governed by the UK Veterinary Medicines Regulations 2013.
Suspected Adverse Reactions Surveillance Scheme (SARSS)
Run by the VMD where any unwanted or adverse reactions to drugs can be reported.
Provides a feedback system for drug reactions and drugs lacking efficacy.
VMD can check drugs with a marketing authorisation are safe and effective
