Psychotherapeutics and dental correlations Flashcards
Review the functions of inhibitory and excitatory neurotransmitters
Excitatory NTs
• Acetylcholine, Noradrenaline, Glutamate
• Influx of Na+ -> Depolarisation -> Action potential
Inhibitory NTs
• GABA, Glycine
• Opens potassium channels and so K+ leaks out of neuron
• Negatively charged chloride ions come into neurone
• Causes overall hyperpolarisation-> Difficult to reach threshold
Describe the pathophysiology of depression
• Monoamine theory: depression is caused by low levels of monoaminergic neurotransmitters (noradrenalin and serotonin) and their binding to 5- HT (serotonin) receptors.
The roles of monoaminergic neurotransmitters include:
• Noradrenaline, adrenaline (excitatory): concentration, arousal
• Dopamine (both): motivational behaviour
• Serotonin (inhibitory): satisfaction, mood
List the types of antidepressants
- Monoamine oxidase inhibitors MOIs:
Phenelzine, tranylcypromine, - Serotonin selective reuptake inhibitors SSRIs:
Citalopram, dapoxetine and fluoxetine - Tricyclic antidepresants TCAs:
Amitriptyline, clomipramine, doxepin - Serotonin and noradrenaline reuptake inhibitors
Describe the mechanism of action of serotonin and noradrenaline reuptake inhibitors and tricyclics antidepressants
- Blocks the serotonin and noradrenaline reuptake receptors in the pre-synaptic neuron
- Thus, this leads to an increase of available serotonin and noradrenaline to dock onto the next neuron and cause an action potential
Describe the mechanism of action of monoamine oxidase inhibitor antidepressants
- Monoamine oxidase is a natural enzyme that breaks down serotonin, epinephrine and dopamine
- MAOIs block the effects of this enzyme.
- As a result, the levels of those neurotransmitters increase
- A higher amount of neurotransmitter = action potential of next neuron
Discuss the adverse effects of serotonin
- •• SSRI has minimal impact on saliva
- Hyper- reflexia
- clonus/ tremor
- incoordination
- mental state change
- shivering
- sweating
- diarrhoea
List the oral side effects of antidepressants
- Dry mouth, lips and throat
- Oral soreness or burning
- Increased risk of caries
- Increased risk of candidiasis
- Dysgeusia
- Halitosis
- Difficulty in chewing, swallowing and speaking
- Impair retention of dentures, denture induced mucosal ulceration
Describe the mechanism of action of antipsychotics and their side effects
- Excessive neurotransmission of dopamine is associated with schizophrenia
- Blocks dopamine receptor (in particular the limbic system)
Side effects: Many effects may be irreversible • Sedation • Anxiety • Agitation • Orthostatic hypotension • Tachycardia • Dry mouth
Describe the mechanism of action for drugs for anxiety and the associated adverse side effects
- GABA is an integralinhibitory neurotransmitter; itlowers the activityof neural cells in the brain and central nervous system
- By inhibiting neural activity, GABA facilitates sleep, reduces mental and physical stress, lowers anxiety, and creates a calmness of mood
- Drugs for anxiety activate GABA’s inhibitory effects on the CNS
Side effects: Drowsiness, light headedness, memory loss, hypersalivation, dependence, blurred vision.
Describe how dental phobic patients are managed
- Anxiolysis/ minimal sedation: low dosage drug for treating anxious patients. Person is very relaxed but awake. Ventilation and cardiovascular functions are unaffected
- Conscious sedation: medicines that cause relaxation (a sedative) and block pain (an anaesthetic) during treatment
- Could be given the night before treatment to ensure restful sleep or preoperatively to lower anxiety
The two drugs include: Temazepam OR Diazepam
Describe psychostimulant drugs used for ADHD
Dexamfetamine and Lisdexamfetamine
- Stimulants work by increasing levels of the neurotransmitter dopamine in the brain
- Dopamine helps with motivation, attention, and movement
- Stimulant medications boost concentration and focus while reducing hyperactive and impulsive behaviours.
Describe other drugs used for ADHD
Atomoxetine
- Atomoxetine is a noradrenaline reuptake inhibitor
- Higher levels of noradrenaline increase alertness and make people feel ready for action.
- It provides an increased wellbeing and more energy
- Thus, it increases attention span and concentration, preventing impulsive behaviour
List the oral manifestations of ADHD
- Decreased attention span = poor OH
- Increased caries
- Bruxism
- Risk for trauma
