Various classes of medications have been evaluated
in the treatment of fibromyalgia, including:
Tricyclic anti-depressants
Tricyclic anti-depressants that are commonly used
in the treatment of fibromyalgia include Amitriptyline
(Elavil), Nortriptyline (Pamelor), and Doxepin (Sinequan).
Amitriptyline is perhaps the most common as its efficacy
has been demonstrated in controlled studies and it is
known to enhance stage 3 and 4 sleep.
In a study of 70 fibromyalgia patients that evaluated
the efficacy of 50 mg of Amitriptyline, patients
receiving the Amitriptyline had significantly improved
quality of sleep, morning stiffness, pain analog and
global assessment. Interestingly, tender point score
did not improve. (40)
Common side effects of Amitriptyline may include morning
sedation, dry mouth, confusion and urinary retention.
Fibromyalgia patients seem especially sensitive to these
side effects. Therefore, the dose should be individualized
and generally begun at the lowest possible dose (such
as 5 to 10 mg) at nighttime. Taking the drug 1 to 2
hours prior to sleep can minimize difficulties with
morning sedation or "hangover". If there is
no response, the dose can increase after 2 to 3 weeks.
Muscle relaxants
Muscle relaxants such as Cyclobenzaprine (Flexeril)
and Orphenadrine Citrate (Norflex) have also been studied
in the treatment of fibromyalgia. Cyclobenzaprine has
a tricyclic chemical structure similar to Amitriptyline,
yet its anti-depressant effects are minimal. It is used
only as a short-term muscle relaxant
In a study of 120 fibromyalgia patients, those receiving
Cyclobenzaprine (10 to 40 mg) over a 12 week
period had significantly improved quality of sleep and
pain score. There was a trend towards improvement in
fatigue symptoms but not in duration of morning stiffness.
Interestingly, there was also a reduction in the total
number of tender points and muscle tightness. (41)
For use in treating fibromyalgia, common beginning
dosages are generally 5 to 10 mg at bedtime. Again,
common side effects include dry mouth, drowsiness, and
constipation.
Orphenadrine Citrate (Norflex) is a centrally
acting analgesic muscle relaxant. It is used as an adjunct
to rest, physical therapy and symptomatic measures for
acute musculoskeletal pain.
In an abstract that reviewed the response of Orphenadrine
Citrate in 85 fibromyalgia patients, over a one-year
period a significant, sustained improvement in general
pain was noted in 34% of patients taking Orphenadrine
Citrate (vs. 15% and 10% of patients taking Amitriptyline
and Cyclobenzaprine, respectively).
The usual short-term dosage is one tablet (100 mg).
Common side effects include confusion, anxiety and tremors,
dry mouth and tachycardia. A few contra-indications
include glaucoma, prostatic hypertrophy, pyloric/duodenal
obstruction or stenosing peptic ulcers. With prolonged
use, periodic monitoring of blood, urine and liver function
tests are recommended.
Sedative/hypnotics
Sedative/hypnotics may also have a role in the comprehensive
management of fibromyalgia. Because fibromyalgia patients
typically report that their sleep is not refreshing,
some physicians may recommend the use of sedatives/hypnotic
medications to enhance sleep.
Temazepan (Restoril), Flurazepan (Dalmane) and Triazolam
(Halcion) are Benzodiazepine agents commonly used for
short-term management of insomnia. Controlled, double
blind studies of their efficacy and safety for fibromyalgia
patients have not yet been conducted. Anecdotally, one
physician found "total resolution of symptoms within
1 to 4 weeks" in 10 of 14 fibromyalgia patients
(5). Dosages, administration and method of evaluation
and side effects were not reported.
Common side effects of these sedative/hypnotic drugs
include excessive drowsiness, confusion, nausea, tachycardia,
nightmares and even (paradoxically) insomnia. Contra-indications
include pregnancy and glaucoma. These drugs are not
recommended for long-term use, and withdrawal symptoms
have been reported.
Non-steroidal anti-inflammatory
drugs (NSAID’s)
NSAID’s have commonly been used to treat fibromyalgia.
Fibromyalgia patients most commonly report generalized
pain and stiffness. NSAID’s are commonly used for
their anti-inflammatory and analgesic (pain-killing)
properties (43,44).
Unfortunately, despite their widespread use, NSAID’s
have not been shown to be very effective in relieving
the painful symptoms of fibromyalgia. There is no documented
evidence of inflammatory changes associated with this
syndrome.
In a study of 46 fibromyalgia patients that compared
Ibuprofen to placebo, both groups reported interval
improvement in fatigue, pain, tender points, and subjective
swelling and there was no significant difference between
the two groups (44).
In another 6 week study of 62 fibromyalgia patients,
groups of patients were given the tricyclic anti-depressant
Amitriptyline, the NSAID Naproxen, both drugs or neither
drug. Although there was initial improvement in pain
at two weeks in the Naproxen group, the difference was
not significant.
While these studies do not demonstrate the efficacy
of NSAID’s for fibromyalgia patients, they may
have clear benefits for fibromyalgia patients with concomitant
and exacerbating conditions such as osteoarthritis,
rheumatoid
arthritis, or other conditions.
Cortico steroids
Steroids have been assessed for treatment of fibromyalgia.
In a two-week study to assess the efficacy of Prednisone,
there was no significant difference between the Prednisone
or placebo or baseline (46). However, it is thought
that a therapeutic trial of Prednisone may be beneficial
for the patient if a co-existent, steroid responsive
disorder is suspected.
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