Exam 3 - Behavioral Medicine Flashcards
(243 cards)
MAJOR DEPRESSIVE DISORDER
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Pharmacotherapy
Older agents are less specific and have a smaller therapeutic index. Ex: TCA.
2-3 fold OD = fatal.
Newer agents are more specific and have a wider therapeutic index. Ex: SSRIs.
Multiple fold OD = OK.
Placebo
Placebo effect takes place with anti-depressant medications, makes it difficult to determine if therapy is effective.
Trials confounded with placebo affect, some trials have poorly defined outcomes.
Depression, can be secondary to:
- Hypothyroidism
- Parkinson’s disease
- Inflammatory conditions
What medications can cause depression?
Beta Blockers
Levetireacetam (Keppra)
Isotretinoin
Topiramate (Topamax)
Clonidine
Corticosteroids
OC
Methyldopa
Interferons (Ribovirin)
Tamoxifen
Anxiety
- GAD, OCD, Panic disorder, PTSD, Phobias
- Can inhibit normal function; often associated with depression.
Why do people get depressed?
- Due to depressed levels of monoamines (serotonin, NE).
- Experience depression due to deficiency of catelcholamines.
-Meds address the issue to supplement the catelcholamines.
Reserpine
Antihypertensive; causes synapses to kick out catelcholamines, so they get metabolized.
Causes a deficiency of NE, epi. In addition to hypotension/bradycardia from drug, you’d see depression develop in patients.
If you give drugs to increase serotonin and fix deficiency, you should see “immediate” effect on depression.
Why don’t the drugs work immediately?
Therapeutic effect of drugs take weeks to become effective; can be 4-6 weeks.
A lot of pts D/C therapy early, so need to let them know therapeutic effect takes a while.
Mechanism of depression
- Downstream effects:
- Receptor expression
- Gene transcription
- No final theory how antidepressants work; just know they work
Three phases of treatment
Acute phase
Continuation phase
Maintenance phase
Often requires lifetime therapy.
Especially for recurrent symptoms.
Situational based - can get away with short-term therapy
Acute phase
First 6-12 weeks of treatment
- Remission of symptoms
- Important to educate patients on increased risk of SUICIDE during this time.
Continuation phase
4-9 months into treatment:
-Eliminate residual symptoms to prevent recurrence.
Maintenance phase
12-36 months into treatment:
-Prevent recurrence.
Non-pharmacologic therapy
Psychotherapy
-Affects are additive with antidepressants
ECT
Repetitive transcranial magnet stimulation (TMS)
PHARMACOLOGICAL THERAPY
..
How do you know what antidepressants to give?
Can’t predict which agent a patient will respond to.
Choice made empirically:
- history of response
- concurrent medical illness
- presenting symptoms
- cost
- drug to drug interactions
- ADR profile
- Patient preference
Escitalopram (Lexapro)
Causes anorgasmia
Antidepressants
How long does it take to reach therapeutic effects?
- 2 to 6 weeks for therapeutic effects
- Adverse effects occur within hours to days
- 20-30% failure rate with antidepressants
Failure Rate
- Intrinsic resistance to therapy
- Due to inadequate dosage or duration
- Noncompliance
- ADR or delay in therapy
Placebo effect efficacy/recurrence
- 30-40% efficacy
- Natural remission in 6-12 months
- 50-70% experience recurrence
TCA vs. SSRI
- Same efficacy
- Differ in ADR profiles
- Therapeutic doses and overdose
MAOI (monoamine oxidase inhibitors)
- Oldest class
- Non-specific MAOI A + B inhibitors
- Prevent breakdown of catecholamines 5HT and NE
- Prevent breakdown of NT; get more NT in synapse
TCA (tricyclic antidepressants)
- Inhibit reuptake of 5HT and NE
- More NT in synapse
SSRI (Selective serotonin reuptake inhibitors)
Specifically inhibit reuptake of 5HT to leave in synapse