Psychopharmacology Flashcards
What are the principles for prescribing in psychiatry
- Establish a diagnosis
- identify the target symptoms that will be used to monitor therapy response
- Choose a suitable agent and dosage
How do you chose the agent and dose
Select an agent with acceptable side effect profile
Use the lowest acceptable dose.
Keep to simplest regime
Describe the management of psychiatric drugs
Adjust dosage for optimum benefit, safety and compliance
Keep in mind the delayed response for many psych meds and the drug to drug interactions they can have. Delay of 3-6 weeks before maximum dose is in body
If no improvement after 2 months of adequate dose, switch to another antidepressant or use another agent
What are antidepressants used for
Unipolar depression Bipolar depression Organic mood disorders Schizoaffective disorder Anxiety disorders, OCD Panic attacks Social phobia PTSD
What is the best antidepressant
There is no one antidepressant that works better than any other as a first line treatment
Second like there is good evidence for metrazipine
What would influence your decision of what antidepressant to use?
Past history of response
Side effects profile
Other medical conditions
What are the different classes of antidepressants
Tricyclics antidepressants
Monoamine oxidase inhibitors (MAOIs)
Selective Serotonin Reuptake inhibitors (SSRI’s)
Serotonin/noradrenaline reuptake inhibitors (SNRI’s)
Novel antidepressants
Describe the use of tricyclics antidepressants
Very effective but side effects can be strong
Have an effect on seratonin and norepinephrine. Also have antihistaminic, anticholinergic, antiadrenergic affects
Can be lethal to overdose, a one week course can be lethal
Can cause QT lengthening
What are tertiary tricyclics
Have tertiary amine side chains which react with other receptors leading to more side effects
Act predominantly on serotonin receptors
Amitriptyline, Imipramine, dosepin, cloipramine
Contain active metabolites including deipramine and notrptyline
What are the side effects of tertiary TCA
Antihstaminic affects (sedation and weight gain) Anticholinergic affects-dry mouth, dry eyes, constipation memory deficits and potentially delirium) Antiadrenergic affects- orthostatic hypotension, sedation, sexual dysfunction)
What are the secondary trycyclic antidepressants?
Are often metabolites of tertiary amines
Primarily block noreadrenaline
Side affects are the smae but generally less severe
E.g. Desipramine, notriptyline
What do you need to know about tricyclics antidperssants
They exist
What they do
A few names of the most common ones
What are monoamine oxidase inhibitors
Bind irreversibly to monoamine oxidase thereby preventing inactivation of aminesnsuch as norepinephrine, dopamine mad serotonin leading to increased synaptic levels
They are very effective for depression
What are the side effects of monoamine oxidase inhibitors
Orthostatic hypotension weight gain Dry mouth Sedation Sexual Dysfunction Sleep disturbance
What is the cheese reaction
Cheese
Red wine
Processed meats
Beans (not baked?)
Hypertensive crisis caused by MAOI’s taken with tyramine-rich foods or sympathomimetics