A large double-blind, vehicle-controlled study of 143 patients with chronic postherpetic neuralgia (PHN) was performed to evaluate the degree of efficacy of topically applied capsaicin 0.075% cream. In addition, the safety and efficacy of long-term application of topical capsaicin in PHN was assessed by following patients in an open-label study for up to 2 years. In the double-blind phase, 143 patients with PHN of 6 months' duration or longer were enrolled. Since epidemiologic studies of patients who receive no treatment have shown that only 10% to 25% of those with PHN after 1 month will still have pain at 1 year, two separate efficacy analyses were performed: one with all evaluable patients (n = 131) and the other with 93 patients whose PHN lasted for longer than 12 months prior to study startup. All efficacy variables, including the physician's global evaluation of reduction in PHN pain, changes in pain severity on the categoric scale, visual analogue scale for pain severity, visual analogue scale for pain relief, and functional capacity scale, showed significant improvement at nearly all time points throughout the study for both patient groups, based on duration of PHN pain. In contrast, the group receiving vehicle cream remained essentially unchanged. Data from the long-term, open-label phase (up to 2 years, n = 77), which immediately followed the 6-week blinded phase, showed that the clinical benefit in patients treated for a short (6-week) period with topical capsaicin could be maintained or amplified in most patients (86%) during prolonged therapy. There were no serious adverse effects observed or reported throughout the trial; in fact, the only side effect associated with capsaicin treatment was the burning or stinging at local sites of application (in 9% of patients) during exposures of up to 2 years (long-term phase). On the basis of these data, we conclude that capsaicin 0.075% cream is a safe and effective treatment for the pain of postherpetic neuralgia and should be considered for initial management of patients with this condition.

Some reports indicate that topical nasal treatment with capsaicin, which is usually effective in reducing symptoms of vasomotor rhinitis, may also reduce symptoms in patients with nasal polyps. The aim of this study was to investigate the effect of topical capsaicin treatment in severe sinonasal polyposis. Nine non-allergic, non-asthmatic patients with diffuse eosinophilic nasal polyposis were subjected to topical capsaicin treatment: for 3 consecutive days 0.5 ml 30 micromol/l capsaicin solution and on days 4 and 5 100 micromol/l capsaicin solution was sprayed into each nostril. Coronary computed tomography (CT) images were made shortly before treatment. Baseline nasal lavages and a questionnaire containing subjective symptoms and nasal endosocpy were taken just prior to the first application. Nasal lavages were performed prior to and after the last treatment and over 4 weeks, endoscopy and subjective scores at each weekly visit, and correspondent CT scans 4 weeks after the treatment. CT images were analysed by computer, calculating the nose sinuses air volume (NSAV) from the surface of aerated parts of nasal and sinus cavities for each slice per patient prior to and after treatment. Statistical analysis was performed comparing NSAV, subjective scores, endoscopy scores and eosinophil cationic protein (ECP) levels in nasal lavages prior to and after treatment. Topical treatment with capsaicin significantly increased NSAV and very significantly improved subjective and endoscopy scores, but did not significantly alter ECP levels in nasal lavages.

BACKGROUND:Animal and some human studies have indicated that the consumption of chili-containing meals increases energy expenditure and fat oxidation, which may help to reduce obesity and related disorders. Because habitual diets affect the activity and responsiveness of receptors involved in regulating and transporting nutrients, the effects of regular consumption of chili on metabolic responses to meals require investigation.

OBJECTIVE:The objective was to investigate the metabolic effects of a chili-containing meal after the consumption of a bland diet and a chili-blend (30 g/d; 55% cayenne chili) supplemented diet.

DESIGN:Thirty-six subjects with a mean (+/-SD) age of 46 +/- 12 y and a body mass index (in kg/m2) of 26.3 +/- 4.6 participated in a randomized, crossover, intervention study with 2 dietary periods (chili and bland) of 4 wk each. The postprandial effects of a bland meal after a bland diet (BAB), a chili meal after a bland diet (CAB), and a chili meal after a chili-containing diet (CAC) were evaluated. Serum insulin, C-peptide, and glucose concentrations and energy expenditure (EE) were measured at fasting and up to 120 min postprandially.

RESULTS:Significant heterogeneity was observed between the meals for the maximum increase in insulin and the incremental area under the curve (iAUC) for insulin (P = 0.0002); the highest concentrations were with the BAB meal and the lowest with the CAC meal. When separated at the median BMI (26.3), the subjects with a BMI>or = 26.3 also showed heterogeneity in C-peptide, iAUC C-peptide, and net AUC EE (P<0.02 for all); the highest values occurred after the BAB meal and the lowest after the CAC meal. Conversely, the C-peptide/insulin quotient (an indicator of hepatic insulin clearance) was highest after the CAC meal (P = 0.002).

CONCLUSION:Regular consumption of chili may attenuate postprandial hyperinsulinemia.

Uncontrolled studies have indicated that topically applied capsaicin may be a safe and effective treatment for postherpetic neuralgia. In a double-blind study 32 elderly patients with chronic postherpetic neuralgia were treated with either capsaicin cream or its vehicle for a 6-week period. Response to treatment was evaluated by visual analogue scales of pain and of pain relief, together with changes in a categoric pain scale and in a physician's global evaluation. Significantly greater relief in the capsaicin-treated group compared with vehicle was observed for all efficacy variables. After 6 weeks almost 80% of capsaicin-treated patients experienced some relief from their pain. Because capsaicin avoids problems with drug interactions and systemic toxicity, we suggest that topical capsaicin be considered for initial management of postherpetic neuralgia.