Behaviour Modifying Drugs 1/2 Flashcards
Drug Classes used to modify behaviour target key neurotransmitters (5)
-Norepinephrine
-Serotonin
-Acetylcholine
-Dopamine
-GABA
4 ways to use drugs manage unwanted behaviours
-Decrease arousal
-Decrease excitability
-Decrease impulsivity
-Promote calming
Drug classes that ______ central serotonergic activity may produce a
______ in aggression
increase; decrease
-decrease tendency to engage in sudden outbursts
- increase threshold of tolerance to potentially aggressive stimuli
what type of drugs can be beneficial for compulsive disorders
TCA’s, SSRI’s and Opioid antagonists
what do fear/anxiety/phobia behaviours benefit from
anxiolytics
what will treatment duration vary with (4)
o Unwanted behaviour and species
o Drug class
o The “individual”
o Owner’s ability to comply with all aspects of therapy
most patients are on _______ therapy
long term
issues with transdermal drug delivery
-Generally, has yielded poor to variable drug levels and efficacy
- But Useful in animals that are challenging to medicate orally long-term
what happens if the drug doesnt work? (4)
-Remember clinical responses take time (~5 half-lives before steady-state, Modification of receptor systems also takes time)
-Dose modification possible; caution with ADRs
-Consider switching drug classes
-Consider combination drug therapy
most behaviour drugs are metabolized by the ____
liver
quality of CNS penetration of psychotropic drugs
generally very good…. for BBB and blood-CSF barrier
Many behaviour drugs used in veterinary medicine are ___ ____ and why
weak bases
o Good lipophilicity
o Protein binding generally low
drugs with long vs short 1/2 life
o Drugs with short t½’s do not accumulate; need to be given
frequently
o Drugs with long t½’s can partly explain the lack of immediate effects of some psychotrophic drugs
what are the principal anxiolytic in vet med
benzos
how do anxiolytics work
Work through potentiation of the GABA-A receptors; Anxiolytic effects believed due to modulation of 5-HT and NE neurons in the CNS
other effects of anxiolytics aside from anxiety
o Central muscle relaxation, sedation
o Seizure suppression
what is used to reverse benzos?
flumazenil, a benzo antagonist
side effects of benzos (4)
-Disinhibition possible; caution or avoid use in cases of aggression
-Paradoxical excitement and amnesia possible
-Idiosyncratic hepatotoxicity in cats possible with diazepam; not yet seen with other BZDs
-Sedation, muscle relaxation, ataxia and hyperphagia
what species can you use diazepam in chronically and why
-Has short half-life in dogs (~1 hr) compared to cats (~5.5 hr)
-Active metabolites with longer-half lives make it suitable for chronic use in cats only
three benzos used in vet med
-diazepam
-alprazolam
-lorazepam
when is use of alprazolam promising
o Higher potency BZD; promising in dogs with panic disorders where a rapid response is needed
o Higher doses may also be needed for panic states over generalized anxiety
when is lorazepam good to use
o Not as extensively metabolized by liver before excretion;
o Advantages in liver failure, geriatrics and cats possibly
what is the name of a nonbenzo anxiolytic
buspirone
how does buspirone work
o Acts as a partial agonist at 5-HT receptors
o Does not compete directly with
BZDs
o Used for generalized anxiety; poor immediate effects
o Less sedating and other side effects than BZDs; No withdrawal effects; less abuse potential