Lecture 3 - management of CNS disorders in children and adolescents Flashcards
what are conditions seen in routine practice of child and adolescent mental health services?
- neurological disorders - conditions characterised by impairments in congisiiton, communication, behaviour and/or motor skills resulting from brain development eg communication disorder ASD, ADHD
- emotional and behavioural disorders - internalising or externalising problems as a consequence of stressful environment - depression anxiety, EDs
what are common psychotropic drugs used in CAMHS
antidepressants, antipsychotics, AEDs, psychostimulants, miscellaneous - hypnotics, anxiolytics,a adrenergic agents. majority are unlicensed in this population.
what are prescribing issues in CAMHS ?
some children are unable to swallow alert tablets or capsules or cannot tolerate bitter or unpleasant taste - parents or surfing staff will mix medicines in foodstuff or drinks - effect on drug stability and efficacy?
pharmacokinetics and drug disposition differ between preschool school age, greater metabolic capacity - more rapid elimination of drugs so higher doses
describe antiphyscotics and main symptoms they are used to address.
typical antipsychotics (first generation) and atypical antipsychotics (second generation) used for psychosis, bipolar disorder, ASD associated stereotypes, compulsions aggression and self injurious behaviours. they address main symptoms of delusions, paranoia, disrderdered thinking which can be useful to deal with aggression, irritability
what is the antipsychotic first generation and second generation receptor profile?
first generation - affinity for agonist for D2
2nd generation - target dopamine and serotonin receptors
explain 1st/2nf generation antipsychotics
both as effective as each other - except clozapine.
2nd gene (SGAs) less likely to cause extrapyramidal side effects, hyprolactinaemia and sexual dysfunction
SGA show some efficacy against positive and negative symptoms
SGA more cardiac toxic, cause weight gain/ hypoglycaemia - metabolic syndrome
what monitoring is required when taking aeds?
weight/ BMI: initially and every 3 months
ureas and electrolytes: baseline and yearly blood glucose and lipids: initially and every 3 months
prolactin: if symptoms of hyperprolactinaemia present
ECG: initially if patient cardiac risk
LFTs: baseline and yearly
what are contributing factors that may cause attention deficit hyperactivity disorder?
ADHD has an unknown aetiology ie exact causes and processes are unknown
- genetics (dopamine receptor or transporter gene)
- prenatal factors (smoking, illicit drugs/ POM)
-premature birth
- environmental toxins
what is used to treat ADHD approach?
multimodal approach.
usually educational support but then to take a step further:
1. stimulants (1st line is methylphenidate, if not tolerated then try dexamfetamine)
2. atomoxetine OR guanfacine (sloe release product)
3. clonidine (mainly to augment therapy but is unlicensed)
what is the mechanism of action of stimulants methylphenidate and dexamfetamine?
dexamfetamine facilitates the release of dopamine from presynaptic cytoplasmic storage vesicles (increase in synapse) and blocks dopamine transporter protein (inhibits reuptake). By inhibiting the reuptake of dopamine, dexamphetamine increases the concentration of dopamine in the synaptic cleft (the gap between neurons).
This elevated dopamine level enhances dopamine signaling in certain brain regions, including the prefrontal cortex, which is crucial for attention and executive functions
methylphenidate acts primarily on the dopamine transporter and has little effect on synaptic release. The increased presence of dopamine in the synaptic cleft leads to enhanced dopamine signaling in certain areas of the brain, particularly the prefrontal cortex.
The prefrontal cortex is involved in executive functions, including attention, working memory, impulse control, and organization. It’s an area often implicated in ADH
what are the brand of methylphenidate and dexamfetamien and the release time.
methylphenidate immediate release effective for 3-4 hrs
methylphenidate sr : equasym XL - 8-10 hrs
medicines XL - 8hrs
concerta XL - 12 hrs
racemic mixture - therapeutic effect is mainly due to the d enantiomer
dexamfetamien immediate release tablets only.
what is atomoxetine?
generally not as good in children. primarily an inhibitor of norepinephrine. makes you drowsy.
what are non stimulant drugs used to treat adhd?
guanfacine - susteaniend release preperation. long time to get a therapeutic effect about 2-3 weeks. has calming effect - may be useful in aggressive/challenging behaviour and in reducing tics.
clonidine - unlicensed for ADHD. 2-3 times a day dosing. longest time to reach therapeutic dose 150-200 mcg a day.
what monitoring is required when taking stimulants?
baseline hr and bp. repeat every dose adjustment and every 6 months.
pre treatment height and weight on growth chart and every 6 months
what medications are used for Tourettes and associated conditions?
antipsychotics/ neuroleptics: ariprprazole, sulphide, risperidone, haloperidol.
clonidine
