A comparison of two formulations of intradermal capsaicin as models of neuropathic pain in healthy volunteers

Simple item page
dc.contributor.authorGustafsson, H.
dc.contributor.authorAkesson, J.
dc.contributor.authorLau, C.
dc.contributor.authorWilliams, D.
dc.contributor.authorMiller, L.
dc.contributor.authorYap, S.
dc.contributor.authorRolan, P.
dc.date.issued2009
dc.description.abstractAIMS: To compare the dose–response relationships of two formulations [Tween- or hydroxypropyl-b cyclodextrin (HP-b-CD)-based] of intradermal capsaicin in healthy volunteers and to assess the effect of potential covariates of response. One, 10, 30 and 100 mg in 10ml were compared for the outcomes of flare, spontaneous pain, mechanical allodynia and hyperalgesia in eight healthy men and eight healthy women. RESULTS: The formulations produced comparable responses at doses 1, 10 and 30 mg, but in all parameters the response was less at 100 mg with the Tween formulation.Mean area for hyperalgesia was 9 cm2 [95% confidence interval (CI) 5, 13] higher with the HP-b-CD formulation. Flare area was 5 cm2 (95% CI 8, 13) greater with the HP-b-CD formulation. There was a significant difference between pain responses from the injection site on the upper forearm compared with the lower forearm on all four pain assessments. In contrast, significant differences were seen in pain response between nondominant and dominant arm for flare, allodynia and hyperalgesia but not for spontaneous pain. A significant difference in sex was seen only for hyperalgesia. The nominal 100-mg dose of the Tween formulation contained only 39% of label strength in the aqueous phase, which may explain the lower pharmacodynamic response. CONCLUSION: The formulations are comparable over the dose range 1–30 mg. The significantly lower pain response at the 100 mg dose in the Tween compared with the HP-b-CD formulation is likely to be due to limitations in solubility at the 100 mg level. Given the greater ease of formulation and the superior dose–response relationship, the HP-b-CD formulation is preferable for use in the model in future studies.
dc.description.statementofresponsibilityHelena Gustafsson, Johanna Akesson, Chai Li Lau, Desmond Williams, Lisa Miller, Sharon Yap and Paul Rolan.
dc.identifier.citationBritish Journal of Clinical Pharmacology, 2009; 68(4):511-517
dc.identifier.doi10.1111/j.1365-2125.2009.03489.x
dc.identifier.issn0306-5251
dc.identifier.issn1365-2125
dc.identifier.urihttp://hdl.handle.net/2440/56250
dc.language.isoen
dc.publisherBlackwell Publishing Ltd
dc.source.urihttps://doi.org/10.1111/j.1365-2125.2009.03489.x
dc.subjectSkin
dc.subjectHumans
dc.subjectPain
dc.subjectHyperalgesia
dc.subjectCapsaicin
dc.subjectbeta-Cyclodextrins
dc.subjectSensory System Agents
dc.subjectExcipients
dc.subjectChromatography, High Pressure Liquid
dc.subjectInjections, Intradermal
dc.subjectSingle-Blind Method
dc.subjectSex Factors
dc.subjectDose-Response Relationship, Drug
dc.subjectTime Factors
dc.subjectAdult
dc.subjectMiddle Aged
dc.subjectFemale
dc.subjectMale
dc.subjectHot Temperature
dc.subjectYoung Adult
dc.subject2-Hydroxypropyl-beta-cyclodextrin
dc.titleA comparison of two formulations of intradermal capsaicin as models of neuropathic pain in healthy volunteers
dc.typeJournal article
pubs.publication-statusPublished

Files

Collections

Pharmacology publications