Arthritis Rheum. 2004 Feb 15;51(1):9-13.
Treatment of fibromyalgia with cyclobenzaprine: A meta-analysis.

Tofferi JK, Jackson JL, O'Malley PG.

Walter Reed Army Medical Center, Washington, DC and Uniformed Services University of the Health Sciences, Bethesda, MD.

OBJECTIVE: To systematically review the effectiveness of cyclobenzaprine in the treatment of fibromyalgia. METHODS: Articles describing randomized, placebo-controlled trials of cyclobenzaprine in people with fibromyalgia were obtained from Medline, EMBase, Psyclit, the Cochrane Library, and Federal Research in Progress Database. Unpublished literature and bibliographies were also reviewed. Outcomes, including global improvement, treatment effects on pain, fatigue, sleep, and tender points over time, were abstracted. RESULTS: Five randomized, placebo-controlled trials were identified. The odds ratio for global improvement with therapy was 3.0 (95% confidence interval [95% CI] 1.6-5.6) with a pooled risk difference of 0.21 (95% CI 0.09-0.34), which calculates to 4.8 (95% CI 3.0-11) individuals needing treatment for 1 patient to experience symptom improvement. Pain improved early on, but there was no improvement in fatigue or tender points at any time. CONCLUSION: Cyclobenzaprine-treated patients were 3 times as likely to report overall improvement and to report moderate reductions in individual symptoms, particularly sleep.

Online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=14872449&dopt=Abstract cyclobenzaprine Flexeril
[PubMed - in process]




Drug Metab Dispos. 1991 Jan-Feb;19(1):154-62.
Cis-flupentixol metabolites in rat plasma and bile. The first proof of glutathione conjugation at the exocyclic double bond.

Shu YZ, Hubbard JW, McKay G, Hawes EM, Midha KK.

College of Pharmacy, University of Saskatchewan, Saskatoon, Canada.

The plasma and biliary metabolites of cis-flupentixol (cis-FPT) were studied after ip administration to rats. Cis-FPT sulfoxide was found to be the major phase-I metabolite in plasma and bile. Five biliary metabolites were isolated by gradient elution HPLC and characterized by various spectroscopic methods: F1, 1'-S-glutathionyl-10,1'-dihydroFPT sulfoxide; F2, cis-FPT sulfoxide sulfate; F3, 8-O-(or 7-O) glucuronyl-cis-FPT; F4, cis-FPT sulfoxide; and F5, cis-FPT glucuronide. A novel non-enzymatic addition of glutathione (GSH) onto the exocyclic double bond was demonstrated to occur for the first time with not only flupentixol and certain of its metabolites, but also with other psychotropic drugs with a tricyclic nucleus and an exocyclic double bond. Specifically, these nonenzymatic additions of GSH were observed with cis-FPT, trans-FPT, cis-FPT sulfoxide, cis-, trans-dealkylFPT, cis-FPT N-oxide, cis-chlorprothixene, cis-thiothixene, and cyclobenzaprine. Among them, cis-FPT sulfoxide showed the most potent adduct formation activity, and the product was characterized to be identical with the in vivo metabolite F1 of cis-FPT.

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W V Med J. 1991 Mar;87(3):112-4.
Fibromyalgia in children; diagnosis and treatment.

Romano TJ.

Fifteen children (16 years and younger, 10 females, 5 males, mean age 13 years) with juvenile primary fibromyalgia syndrome (JPFS) were seen in a private rheumatology practice over two years. This represented 45 percent of the total number of pediatric rheumatology patients. Symptoms included polymyalgias, polyarthralgias, nonrestorative sleep, difficulty concentrating in school and fatigue. Examination revealed typical tender points, absence of joint swelling, synovitis or nodules and absence of neurological findings. Dolorimetry was abnormal and standard laboratory tests were normal. Most of these patients (67 percent) had seen three or more doctors prior to their rheumatological evaluation and not (60 percent) were told they had juvenile chronic arthritis. Other diagnoses offered were "growing pains" (20 percent), hysteria (7 percent) and psychological problems (7 percent). None of the JPFS patients responded to salicylate or other anti-inflammatory medication. Most (73 percent) responded to cyclobenzaprine, mean dose 12.75 mg. (range 5-25 mg. qhs). JPFS is a very common pediatric rheumatologic problem and is confused with other disorders. Reassurance is very important in the therapy since many parents are fearful that their children may have a potentially crippling disorder. Medication, especially with tricyclics, moderate exercise and proper sleep are also mainstays of therapy.

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Vet Hum Toxicol. 1990 Apr;32(2):133-5.
Skeletal muscle relaxant ingestion.

Lebby TI, Dugger K, Lipscomb JW, Leikin JB.

College of Medicine, University of Illinois Hospital.

We retrospectively analyzed 56 consecutive cases involving acute skeletal muscle relaxant exposure that were reported to the Poison Control Center over a 1-year period. The age range was 9 mo to 56 years (mean 18.9 +/- 13.1) with the site of exposure being the primary residence in 54 cases (96.4%). The reasons for inquiry to the Poison Center were reported to be intentional suicide in 26 cases (46.4%), accidental in 21 cases (37.5%), with intentional misuses in 5 cases (8.9%). No deaths were reported. Eighteen cases (32.1%) were reported with co-ingestants (average number of substances taken was 2.7 +/- 0.8). Of these cases 3 patients (16.7%) had major effects with life-threatening symptoms with 6 (33.3%) patients having no symptoms. Of the remaining 38 cases, 17 (44.7%) wer cyclobenzaprine, 6 (15.8%) were methocarbamol, 5 (13.2%) were carisoprodol, 5 (13.2%) were chlorzoxazone, 3 (7.89%) were Baclofen and the remainder were either life-threatening symptoms (2.6%), while 29 (74.3%) had no or minor effects with symptoms that subsided. We conclude that morbidity and mortality are low in pure skeletal muscle relaxant ingestion, however it may be increased in multiple ingestions.

Online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=2327059&dopt=Abstract cyclobenzaprine Flexeril