Fibromyalgia

Question 1

Amitriptyline (Elavil):

Answer 1

• bedtime dose
• lower than those required to treat depression
• EVEN at low dose : dry mouth, constipation, fluid retention, weight gain, grogginess, and difficulty concentrating are common.
• ADR: uncommon with low doses used to treat pain but could include QT prolongation with over use, orthostatic hypotension, anticholinergic effects (dry mouth, blurry vision, urinary retention..)

Question 2

Cyclobenzaprine (Flexeril):

Answer 2

• dose of 10 mg/day may provide efficacy while minimizing side effects.
• Avoid with tricyclics due to similar pharmacology.
• May increase seizure risk or sedation with tramadol.
• caution with other SR drugs due to risk of SS

Question 3

Duloxetine (Cymbalta):

Answer 3

• In patients unresponsive to or intolerant of amitriptyline
• severe fatigue or who require concomitant drug therapy for depression in addition to pain. It is used at 30-60 mg/day

Question 4

Milnacipran (Brand only: Savella)

Answer 4

• alternative to duloxetine in patients with severe fatigue in addition to pain. 12.5mg once daily then increase to twice daily.
• Milnacipran helps pain, and perhaps fatigue, and function. May help memory problems more than duloxetine, but poses higher risk of increased blood pressure.

Question 5

Venlafaxine (Effexor)

Answer 5

• selective SNRI
• Limited data regarding the efficacy of venlafaxine for fibromyalgia, compared with duloxetine or milnacipran
• Withdrawal symptoms may more readily occur because of the short half-life of this medication if a dose is missed

Question 6

ADR for all SNRIs:

Answer 6

• Increase in blood pressure and heart rate
• decrease in libido
• possible mode change, sweating, restless leg syndrome.

Question 7

Pregabalin (Lyrica)

Answer 7

• in patients unresponsive to or intolerant of amitriptyline and in patients with more severe sleep disturbance in addition to pain.
• ADR: Dizziness, somnolence, mild euphoria (risk of addiction: Schedule 4), blurry vision, weight gain.

Question 8

Gabapentin ( Neurontin)

Answer 8

• used as an alternative to pregabalin in patients for whom cost of the medication or regulatory requirements limit the use of pregabalin.
• ADR: Fatigue, somnolence, fatigue, blurry vision

Question 9

Analgesics

Answer 9

• Capsaicin is not recommended due to limited evidence of efficacy. Side effects might outweigh benefit.
• Opioids other than tramadol should generally be avoided. No evidence of efficacy, with risks of dependence and side effects (e.g., sedation, constipation, hyperalgesia, worsened fatigue).

Question 10

Serotonin syndrome

Answer 10

• Agitation or restlessness
• Confusion
• Rapid heart rate and high blood pressure
• Dilated pupils
• Loss of muscle coordination or twitching muscles
• Muscle rigidity
• Heavy sweating
• Diarrhea
• Headache
• Shivering

Question 11

steps in treating FM pain

Answer 11

1. NonPharm management : Diet, excercise, relaxation therapy,
2. TCA’s ( amitryptiline qhs )
3. Gabapentin or Lyrica
4. Cymbalta or Effexor
5. Tramadol
6. Pain Program