Fibromyalgia Flashcards
What is fibromyalgia
Disengagement from noxious stimuli or healing, not associated with tissue inflammation
Chronic widespread MSK pain with no identified cause- Diffuse hyperalgesia and/or allodynia
AKA “central pain disorder”
In fibromyalgia, pain can be due to
damaged or abnormally functioning PNS and/or CNS
The pathophys behind fibromyalgia is
Disturbance in CNS pain processing
Responsive to neuroactive compounds altering levels of NT involved in pain transmission
In FM, patients perceive noxious stimuli as
heat
electrical current
pressure
Underlying CNS dysfunction is noted in individuals with
Sleep and mood disturbances
The 2011 FM survey criteria is scored 0-31. What are the score ranges
0-19: number of body parts with pain
0-3: presence and severity of fatigue and sleep and memory problems
1 point each for depression, IBS, and HA
*FM is diagnosed at 12 or 13
What is the sub-threshold “fibromyalgianess”
Indicates that more of a persons pain and other Sx are coming from the brain, not a peripheral disorder
Initial approach to those with FM include
confirm Dx
Educate patient on condition
Evaluate and treat comorbidities (mood and sleep disturbance)
Most patients end up doing
Trial with low dose TCA, selected antidepressants, or anticonvulsants
Exercise program
Patients that dont respond to exercise and antidepressants end up
Specialty referral Combo drug therapies PT Psych interventions (CBT) Multidisciplinary programs
Non-pharm treatments for FM include
Patient education Graded exercise CBT, OT, or psych CAM CNS neurostimulatory therapies
Patients taking meds for FM saw
moderate degree of benefit in pain and sleep, but effects on fatigue and QoL were small
Pharmacotherapy for FM includes
Amitryptaline Cyclobenzaprine Duloxetine Milnacipran Gabapentin Pregabalin
What is the MOA of Amitriptyline
TCA that blocks NET and SERT channels
Start at 10mg QHS
-Alternative: Desipramine
ADE of Amitriptyline include
dry mouth constipation fluid retention weight gain grogginess difficulty concentrating
What is the MOA of cyclobenzaprine
Centrally acting skeletal muscle relaxer that is similar to TCA
Can be used for mild to moderate Sx, with minimal antidepressant effect
ADE of Cyclobenzaprine include
drowsiness dry mouth change in mental acuity constipation NM and skeletal weakness blurred vision
What is the MOA of Duloxetine (Cymbalta)
SNRI used in patients with depression- improves mental fatigue, but not general fatigue
Take in AM with breakfast
ADE of Duloxetine include
nausea
HA
dry mouth
(usually w/in first 3 months of therapy)
What is the MOA of Milnacipran and Venlafaxine
SNRI used for severe fatigue and pain
Improves pain, global wellbeing, and physical function
*Venlafaxine is not used much 2/2 more intense withdrawal Sx and short half life
ADE of Milnacipran include
nausea
headache
constipation
What is Gabapentin
anticonvulsant that acts on cellular calcium channels and blocks release of various NT to cause analgesia
Gabapentin is used to
reduce pain
improve sleep and QoL
ADE of gabapentin include
dizziness
sedation
light headedness
weight gain
What is Pregabalin (Lyrica)
Anticonvulsant that binds alpha-2 delta subunits of voltage gated Ca channels in CNA= inhibits excitatory NT release
Reduces glutamate and glutamine levels in posterior insula
Reduces increased functional connectivity between pain regions
Structurally related to GABA, but does not bind GABA or benzo receptors
Pregabalin is used for
More severe sleep disturbances
Pain relief
ADE of pregabalin are
peripheral edema dizziness ataxia xerostomia tremor blurred vision
Less recognized treatments for fibromyalgia include (1A recommendations)
SSRI: Fluoxetine, Sertraline, Paroxetine
Gamma hydroxybutyrate
Cannabinoids
(Naltrexone is a level 2 evidence)
ADE of the less used options are
SSRI: nausea, sexual dysfunction, weight gain, sleep disturbance
GHB: sedation, respiratory depression, death
Cannabinoids: sedation, dizziness, dry mouth
These are NOT considered appropriate Tx for fibromyalgia
NSAIDs: can cause GI, renal, and cardiac s/e
Opioids: not good for treating chronic pain!
