Chapter 15 Psychopharmacology for Pain Medicine Flashcards
A large percentage of patients with chronic pain disorders have coexisting or comorbid
Psychiatric Conditions
Psychotherapeutic modalities
Cognitive Behavioral Therapy, Relaxation training, or Biofeedback
The majority of patients with psychiatric comorbidity developed their psychiatric illness
after the onset of chronic pain
Type of psychiatric illness
Major depression alone affects 30% to 50% of all pain clinic patients, followed by anxiety disorders, personality disorders, somatoform disorders, and substance use disorders.
Most frequently affect patients with chronic pain
Major Depression and Anxiety disorders are the most common and have the best response to medications
According to the DSM-IV, major depressive disorder (MDD) requires two key features
depressed mood and loss of interest or pleasure in most activities (anhedonia) for at least 2 weeks
Major depression can be distinguished from situational depression (also termed “demoralization” or an “adjustment disorder with depressed mood”) by
the triad of persistently low mood, self-attitude changes, and changes in vital sense, all lasting at least 2 weeks. Low mood manifests itself by emotions of “feeling blue,”
down, or depressed.
Anhedonia
the inability to experience pleasure, is a key reflection of low mood
A diminished self-attitude is seen in
thoughts of guilt or thinking that one is a bad person
Changes in vital sense
refer to changes in sleep, appetite, or energy levels.
Depressive symptoms
may present as Beck’s triad, with patients feeling hopeless, hapless, and helpless. They
see the future as bleak, they feel they cannot help themselves, and no one can help them
Suicidal thoughts reflect
the severity of depressive symptoms.
Antidepressants can take up to how long for an initial response and for full clinical improvement?
Antidepressants can take up to 2 to 4 weeks for an initial response, but all can take 4 to 8 weeks for full clinical improvement after a typical dose is reached
For depressed patients who also suffer from comorbid pain should remain on them for how long?
For 6 to 12 months for the treatment of an initial depressive episode, and 5 years for the treatment of a recurrent depressive episode
What group of patients tend to respond at lower doses of antidepressants?
Older adults tend to respond at lower doses of antidepressants, and dose titration should occur more slowly in this group because of
their heightened sensitivity to side effects and toxicity.
Good rule of thumb in starting antidepressants in any age
group
is to begin with 25% to 50% of the standard initial
treatment dose for a week, and then advance gradually
over the next 2 to 3 weeks to the treatment dose. This
minimizes side effects and increases treatment compliance
What drug should not be prescribed with other antidepressants?
Monoamine oxidase inhibitors (MAOIs), such as phenelzine, which are rarely prescribed anymore, should not be prescribed with other antidepressants concurrently
The most efficacious treatment for major depression?
Cognitive behavioral therapy (CBT) in conjunction with
antidepressant therapy
- SELECTIVE SEROTONIN REUPTAKE INHIBITORS (SSRI’s)
Fluvoxamine (Luvox) Fluoxetine (Prozac) Paroxetine (Paxil) Sertraline (Zoloft) Citalopram (Celexa) Escitalopram (Lexapro) Venlafaxine (Effexor)
SSRI Mechanism of Action
They have an immediate effect on the blockade of the presynaptic serotonin reuptake pump in the central nervous system (CNS), to increase the duration of serotonin in the synaptic cleft, increasing the effects of
neurotransmission
Adverse effect that all SSRIs have been associated with
Easy bruising/bleeding and osteoporosis
SSRIs can lead to serotonin syndrome when given with other medications including
SNRIs, TCA, MAOIs, triptans (e.g., sumatriptan), and antiemetics (e.g., ondansetron, metoclopramide).
- A serotonin syndrome can be precipitated by a combination of SSRIs and multiple analgesics, including
Tramadol, meperidine, fentanyl, and pentazocine
The use of SSRIs in combination with tramadol can
Lower the seizure threshold, and caution should be taken if combining these drugs