Pharmacology Flashcards
Why should you not inject into the caudal half of a bird?
Due to the renal portal system- any drug would just be excreted
What 3 things pose an issue with exotic pharmacology?
Small muscle masses
Renal portal system
Few licenced products
Why should you not medicate via the water bowl?
Most sense it and therefore do not drink
What’s the risk of injecting into a rabbits marginal ear vein?
Risk of sloughing
Name a muscle and vein you could inject into in a rabbit and ferret
Cephalic
Cranial quadriceps
If giving birds medication orally/enterally what do we need to do?
Stomach tube them
Where is best for a SC injection in birds?
Skin on inner thigh 1/2 way between body and stifle
IM muscles in birds are sometimes given in the pectorals. Which two birds can you not do this with?
Emus- not as well developed as these builds don’t fly
Neonates- as also little development
Why do you need to avoid the cranial lateral thigh?
Renal portal system
Which vein could you inject into in a bird!
Right jugular
Which bone could you put drugs into in a bird?
Which would you avoid and why?
Distal ulna
Humerus as its pneumatic (and injecting would let the air out)
Why can you not give drugs to reptiles that are not eating?
The GI tract shuts down between meals
Are s/c injections practical in reptiles?
No
Reptiles have a renal portal system to avoid injecting caudally. Where could you give IM injections in lizards and chelonions? Where in snakes?
Lizards and chel: upper arm
Snake: epaxials
Veins to sample in chelonions?
Lizards and snakes?
Right jugular
Tail vein
Lizards are the only reptiles when you can do an IO injection. Which is the only bone you can use?
Proximal tibia
Name the bacteriocidal antibiotics
Remember: cats are my favourite pets. (Not Norman, would kill him, therefore cidal)
Cephalosporins Aminoglycosides Metronidazole Fluoroquinolones Penicillin
Pen and Ceph stop cell wall synthesis
Fluro and metron effect DNA
What do aminoglycosides do?
Inhibit protein synthesis
Name the static antibiotics
Remember: mum, Tilly, laura, Sky, cuddle (all the girls cuddle)
Macrolides Tetracyclines Lincomysin Sulphonamides Chloramphenicol
All these drugs inhibit protein synthesis, except one. Which one? And what does it do?
Sulphonamides
It inhibits folic acid synthesis
Which antibiotics MUST be avoided in rabbits and why?
Penicillin, cephlosporins, lincosamides and macrolides
Because they wipe out resident microorganisms therefore disrupt the normal floral
What is baytril?
Enrofloxacin
It’s therefore cidal, effects DNA
Baytril is licenced in all exotics. What else is licenced for rabbits and reptiles?
Rabbits:
Sulphatrim (trimethoprim and sulphameth)
Isathal (fucidic acid)
Tiacil (gentamyscin)
Reptiles:
Sulphatrim
What abs are licenced in ferrets?
None
Recap the drug cascade
Must use licenced drug for that animal and condition
If none, can use drug for same animal or same condition
If none, can use human med authorised in UK. Or drug from EU country authorised for food animals
State an ab you have to be careful with in birds and why
Fluros
Because if given IM causes necrosis
Reptiles are exothermic, why is this important to consider with drug admin
If they are kept at the wrong temp they metabolise drugs differently
Which abs do you need to be careful with with reptiles and why?
Aminoglycosides
Because they causes nephrotoxicity
What challenges surround analgesia in exotics
Hide pain
Reptiles metabolise depending on temp
Faster metabolic rates
Limited data
Give an example of a pain scale used in exotics
Mouse grimace scale
What things must you consider when administering analgesics
Will the procedure itself be painful?
Will it damage tissues?
State some signs of pain
Inc HR, inc RR, dec vent, gut stasis, vomitting
When should you give analgesic when it comes to procedures
Before it begins
How do local anaesthetics work?
Give an example of one?
They block ion channels to prevent generation and conduction of pain impulses
Lidocaine (ok for birds, reptiles, rabbits and rodents)
How do opioids work?
Block pain centrally by binding to opioid receptors - they are agonists!
Why are opioids used with pre meds?
Allows us to use less anaesthetic (gas sparing effect)
Give a positive and a negative with regards to opioids
Cause CV and resp suppression
Some can be reversed
Which opioid (receptor against) best in following species: Small rodents/dogs/cats? Birds?
U agonists e.g. Morphine
K agonists e.g. Butorphanol
Think katie bird!!!!
What do NSAIDS do?
Which is preferable 1 or 2??
Give an example of each
They inhibit cyclooxygenase in arachodonic pathway
Cox2 preferable as antiinflam
Cox1 protects GI function normally
E.g. 1= ketoprofen, 2= meloxicam
They are effective in birds, small mammals and reptiles
How do corticosteroids work?
They have an anti inflammatory effect e.g. Preds, dexamethasone,
Give some effects of long term use of glucocorticoids
Immune suppression
Dec wound healing
Inc infection
Why are glucocorticoids not recommended for birds and reptiles
Because they cause immunosupression and therefore could predispose to Mycotic infections in the lungs
What 4 things must a GA include
Loss of sensation
Loss of consciousness
Analgesia
Muscle relaxing
You need a combination of agents to achieve this
Why do you need to be careful with the length of ET tube used IN BIRDS
There trachea narrows distally
Why do rabbits require LA spray before incubating?
Prone to larygospasm
Why should you premed rabbits first and tube them asap?
Because they breath hold and can become hypoxic
Induction can be injectable to inhaled. Maintainence must be via ET tube, using mapleson F for reptiles as need to ventilate and this circuit has lowest resistance.
Isoflurane is safe for all, but why is sevoflurane preferred?
Less respiratory irritant and arguably safer
If a bird is in dorsal recumbency during GA what must we do?
Perform IPPV as pectoral weight and abdominal weight crushes lungs
