Antidepressant and Stabilizers Flashcards
Depression
An effective disorder characterized by loss of interest and pleasure in daily activities
Symptoms of Depression
Diminished interest in activities Decreased concentration, indecisiveness Loss of energy, fatigue Guilt, Excessive guilt, feelings of worthlessness Loss or gain of appetite Sleep insomnia or hypersomnia Psychomotor Suicide
Tricyclic Antidepressants
Effectively relieve depression with anxiolytic and analgesic action
Pharmacologic Properties
- Block presynaptic NE reuptake transporter
- Block presynaptic 5-HT reuptake transporter
- Block reuptake histamine transporter
Block postsynaptic ACh receptor
Have virtually no effect of DA rtransporter
Not selective
Ex. Imipramine(Tofranil), Clomipramine (Anafranil)
Effects of Blocking Transporters
ACh blockade leads to dry mouth, confusion, blurry vision, and mental confusion
Histamine blockage leads to drowsiness and sedation
Can induce cardiac depression and increased electrical irritability, can be fatal during/after OD
Pharmacokinetics TCA
Well absorbed upon oral absorption Relatively long half lives Metabolized in the liver Converted into intermediates that were then detoxified Readily crosses the placenta
Clinical Limitation TCA
Slow onset of action, 2-4 weeks for antidepressant effect to appear
Wide variety of effects on CNS( adverse effects)- can impair attention, memory motor speed and dexterity
Cardiotoxic and potentially fatal in overdoses
Notriptyline
Superior pharmacologic properties compared to all other TCA as psychotropic
Potent as an NRI and has good TI
Safe to combine with MAOI or SSRI
Advantage when treating refractory patients who may require antidepressant drugs
Second Generation Trazedone
Not a potent blocker of NE or 5-HT, its active metabolite blocks a class of 5-HT receptors
Second Generation Bupropion
Selectively inhibits DA reuptake, used for ADHD
Side effects include nausea, anxiety, restlessness, tremors, insomnia
Clomipramine
Sturcutrally a TCA but exerts inhibitory effects on 5-HT reuptake
Desmethyclomipramine
Active metabolite, Mixed 5-HT and NE reuptake inhibitor, used to treat OCD, depresion, panic disorder, phobia disorder
Venlafaxine
Mxed 5-HT and NE reuptake inhibitor, but also inhibits reuptake of DA and improves psychomotor and cognitive function
SSRI
Fluoxetine (Prozac) first released in 1987
Increases the amount of serotonin available to stimulate post synaptic receptors
Can treat depression ADHD, obesity, alcohol abuse, childhood anxiety
Long term- facillitate increased survival and grown of neurons via action on the cAMP response element binding protein and brain derived neurotrophic factor (BDNF)
Reduce glucocorticoids- stress hormone
BDNF lower in depressed patients
Repair neurons, increase neurogenesis, primarily in hippocampal and frontal regions- accounts for the delay in therapeutic response to antidepressant therapy
Nefazodone (Serazone)
Unique antidepressant, resembles TCA as an inhibitor of 5HT and NE reuptake, no therapeutic superiority over TCA and SSRI
Mirtazapine (Remeron)
Increases noradrenergic and serotonergic neurotransmission by blocking alpha autoreceptors and heteroreceptors, a potent antagonist, rapidly absorbed orally
Monoamine Oxidase Inhibitor
1 out of 2 enzymes that break down 5HT and NE
MAO-A inhibition causes antidepressant activity
MAO-B inhibition- causes side effects
Allows more neurotransmitter in synapse
Potential for serious side effects and potentially fatal interactions with other drugs and food
Behavioral Therapies
non-pharmacological treatment useful in treating some depression
Number of well controlled studies is limited, so not clear how effective they are long term
More useful when combining pharmacologic therapies
Exersize may also be helfpful
Medications often needed early in the treatment plan, manage overt symptoms
- As symptoms become less intense, more receptive to behavioral therapy
- Medications eventually reduced, behavioral therapies increased
Long term maintenance with low dose is necessary for some