Topical application of doxepin hydrochloride, capsaicin and a combination of both produces analgesia in chronic human neuropathic pain: a randomized, double‐blind, placebo‐controlled study

Abstract

Aims To assess the analgesic ef®cacy of topical administration of 3.3% doxepin hydrochloride, 0.025% capsaicin and a combination of 3.3% doxepin and 0.025% capsaicin in human chronic neuropathic pain. Methods A randomized, double-blind, placebo-controlled study of 200 consenting adult patients. Patients applied placebo, doxepin, capsaicin or doxepin/capsaicin cream daily for 4 weeks. Patients recorded on a daily basis overall pain, shooting, burning, paraesthesia and numbness using a 0±10 visual analogue scale during the week prior to cream application (baseline levels) and for the 4 week study period. Side-effects and desire to continue treatment were also recorded. Results Overall pain was signi®cantly reduced by doxepin, capsaicin and doxepin/ capsaicin to a similar extent. The analgesia with doxepin/capsaicin was of more rapid onset. Capsaicin signi®cantly reduced sensitivity and shooting pain. Burning pain was increased by doxepin and by capsaicin and to a lesser extent by doxepin/capsaicin. Side-effects were minor. One patient requested to continue placebo cream, 17 doxepin cream, 13 capsaicin and 9 the combination of doxepin and capsaicin. Conclusions Topical application of 3.3% doxepin, 0.025% capsaicin and 3.3% doxepin/0.025% capsaicin produces analgesia of similar magnitude. The combination produces more rapid analgesia.

Governing role of primary afferent drive in increased excitation of spinal nociceptive neurons in a model of sciatic neuropathy

“…Several studies have reported that systemic administration of lidocaine decreases ectopic activity recorded from injured peripheral sensory fibers (Chabal et al, 1989;Devor et al,1992;Omana-Zapata et al,1997a;Sotgiu et al, 1992) and reduces neuropathic pain (Brochu et al, 2006;Erichsen et al, 2003;Sinnott et al, 1999;Smith et al, 2002). Furthermore, systematic reviews of human studies using systemic administration of local anesthetic drugs support their use for neuropathic pain (Kalso et al, 1998) and, in addition, topical or local administration of antidepressants (Lynch et al, 2005;McCleane, 2000) and local anesthetics (Abram, 2000;Galer et al, 1999;Galer, 2002;Galer et al, 2002;Herrmann et al, 2005;Khaliq et al, 2007;Koltzenburg et al, 1994;Meier et al, 2003;Nystrom and Hagbarth, 1981;Roganovic and Mandic-Gajic, 2006;Rowbotham et al, 1996;Varrassi et al, 2006;Vranken et al, 2002) have been demonstrated to be effective in treating neuropathic pain in controlled clinical trials.…”

Acute Pain Management in the Emergency Department

“…The same studies also showed a lower rate of adverse events and improved quality of life [77,79,80]. Topical capsaicin cream has also been studied to reduce neuropathic pain; nonetheless, application of this cream has been associated with a burning sensation in up to 81% of patients [81]. Randomized controlled studies of high concentration topical capsaicin revealed significant pain relief in patients with PHN with relief lasting up to 12 weeks [77,82,83].…”

Vulvodinia: Un Diagnóstico Olvidado Frente Al Dolor Vulvar

“…La sedación y los mareos son frecuentes en el uso de anticonvulsivantes, lo que puede interferir en el tratamiento. Aunque escasas, hay investigaciones que evalúan el uso de doxepina (66), cromolina (67), nitroglicerina (68) y capsaicina (69). También se utilizan infiltraciones con corticoides (70,71).…”