Influence of tropisetron on the serum substance P levels in fibromyalgia patients.

Abstract

BACKGROUND:

Substance P is found at an elevated level in the cerebrospinal fluid of fibromyalgia (FM) patients. Treatment with tropisetron leads in a subgroup of FM patients to pain reduction. The question arises of whether the substance P level in the serum can be changed by tropisetron treatment.

METHOD:

Twenty patients with FM diagnosed according to the ACR criteria were treated for 5 days with a 5 mg tropisetron intravenous (i.v.) bolus injection daily. Before the first injection, 3 h later, and before and 3 h after the last injection, the serum levels of substance P were determined. The determination of this substance was carried out by means of an immunoassay from Assay Design Biotrend, Cologne. To evaluate the success of the tropisetron treatment, patients made a global assessment as 'clearly better', 'better', 'unchanged', or 'poor'. Patients who answered 'clearly better' and 'better' were regarded as responders.

RESULTS:

Of the 20 patients, ten reported a good or very good influence on their pain (responders). In these responders, the means of the serum substance P levels were elevated in comparison with the non-responders, though the difference was not significant. In responders, the 5-HT3 receptor antagonist tropisetron produced a significant decrease in the serum substance P levels, while this did not occur in the non-responders.

CONCLUSION:

It is possible that the responders to tropisetron represent a subgroup of FM patients for whom substance P and 5-HT3 receptors play key roles in the development of the pain symptoms.

• Authors: T Stratz, B Fiebich, U Haus, W Müller
• Journal: Scandinavian journal of rheumatology. Supplement (Scand J Rheumatol Suppl) Vol. 119 Pg. 41-3 ( 2004) ISSN: 0301-3847 [Print] Norway
• PMID: 15515412 (Publication Type: Journal Article)

Chemical References

• Indoles
• Serotonin 5-HT3 Receptor Antagonists
• Serotonin Antagonists
• Substance P
• Tropisetron

Topics

• Female
• Fibromyalgia (blood)
• Humans
• Indoles (pharmacology)
• Middle Aged
• Serotonin 5-HT3 Receptor Antagonists
• Serotonin Antagonists (pharmacology)
• Substance P (blood)
• Time Factors
• Tropisetron