MedPath

Mannitol Cream for Post Herpetic Neuralgia

Phase 1
Completed
Conditions
Neuralgia, Postherpetic
Interventions
Registration Number
NCT02484170
Lead Sponsor
University of British Columbia
Brief Summary

30% mannitol cream has shown its ability to reduce the activation of the Capsaicin (TRPV1) (Transient Receptor Potential Vanilloid 1) receptor, a likely cause of the pain of post-herpetic neuralgia (PHN). This randomized placebo-controlled crossover study compares PHN pain one week before, for one week on the randomly assigned mannitol versus placebo cream and, after a three day washout, for one week on the other cream. Following this crossover study, participants receive mannitol cream for three months. Pain levels will be checked to assess whether continued use of this cream significantly reduces the pain levels associated with PHN. If pain persists beyond 3 months, participants will be offered mannitol and menthol cream for one month following which their pain levels will be checked.

Detailed Description

Pain levels: 0 to 10 Numerical Rating Scale (NRS), medication and alcohol intake will be checked daily for one week prior to randomization in 20 participants with post herpetic neuralgia, lasting more than three months. Following this 10 will be randomized to apply 30% mannitol in vehicle cream and 10 to apply vehicle cream alone for one week during which daily pain levels and use of medication and alcohol will be measured together with the mode of application (rubbing in or applying it to cling wrap then applying the cream coated cling wrap to the skin in cases of severe allodynia). After a three day washout period, they will be given the cream they did not receive previously for one week. The same variables will be recorded daily. The data collected in the first 24 days will be used to generate a power analysis. Following this, all subjects will receive the 30% mannitol cream to apply for three months. Their pain levels, medication intake and method of application will be measured once a month for three months. T-tests will compare the pain levels for mannitol and placebo users before and after one week of the use of each cream to see if the mannitol cream provides better short term pain relief than placebo. Repeated measures ANOVA (Analysis Of VAriance) will compare pain levels before using the mannitol cream and monthly for three months to assess the long-term effects of mannitol cream. Variables collected at each visit, which will not be used for statistical purposes in the current very small pilot project but may be used in a later study, include: application method, effect and side effects of the cream, medication and alcohol use, PHQ - 9 (Personal Health Questionnaire, 9 questions), and questions from the brief pain inventory score. At three months, a satisfaction score will be added to the database. If pain persists beyond 3 months, participants will be offered mannitol and menthol cream for one month, following which their pain levels, PHQ - 9 and brief pain inventory scores will be checked.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
20
Inclusion Criteria

Not provided

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Exclusion Criteria
  1. Allergies to any of the ingredients of the cream

  2. Open lesions or abrasions on the skin where the cream will be applied

  3. Using corticosteroids

  4. Unwilling to stop using other topical products (creams or patches) for the treatment of post-herpetic neuralgia

  5. Pregnant, breast-feeding or not using birth control

  6. Suffering from severe chronic pain from a cause other than post-herpetic neuralgia

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Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
mannitol in vehicle cream /vehicle creamMannitol creamone week on the mannitol cream (mannitol 30% in vehicle cream), a 3 day washout period, and one week on the placebo cream (vehicle cream alone). To be applied over the painful area as needed for pain. Usual frequency is 2 to 3 times daily.
vehicle cream /mannitol in vehicle creamMannitol creamone week on the placebo cream (vehicle cream alone), a 3 day washout period, and one week on the mannitol cream (mannitol 30% in vehicle cream).To be applied over the painful area as needed for pain. Usual frequency is unknown.
vehicle cream /mannitol in vehicle creamPlaceboone week on the placebo cream (vehicle cream alone), a 3 day washout period, and one week on the mannitol cream (mannitol 30% in vehicle cream).To be applied over the painful area as needed for pain. Usual frequency is unknown.
mannitol in vehicle cream /vehicle creamPlaceboone week on the mannitol cream (mannitol 30% in vehicle cream), a 3 day washout period, and one week on the placebo cream (vehicle cream alone). To be applied over the painful area as needed for pain. Usual frequency is 2 to 3 times daily.
Primary Outcome Measures
NameTimeMethod
Change in worst NRS (Numerical Rating Scale) pain scoreBefore each cream is first applied, 7 days later, and for mannitol cream 1,2 and 3 months

In the last 24 hours, how bad was your pain at its worst? No pain 0 1 2 3 4 5 6 7 8 9 10 Worst pain imaginable

Change in average NRS (Numerical Rating Scale) pain scoreBefore each cream is first applied, 7 days later, and for mannitol cream 1,2 and 3 months

In the last 24 hours, how bad was your pain on average? No pain 0 1 2 3 4 5 6 7 8 9 10 Worst pain imaginable

Secondary Outcome Measures
NameTimeMethod
Satisfaction from cream useThree months after use of mannitol cream was started.

How satisfied were you with the use of this cream? Not at all satisfied 0 1 2 3 4 5 6 7 8 9 10 extremely satisfied

Change in pain score from mannitol cream use to mannitol and menthol cream use1st measurement Three months after use of mannitol cream was started 2nd measurement one month after mannitol and menthol cream started

Maximum pain score after 3 months of mannitol cream use compared to maximum pain score after one month of mannitol and menthol cream use

Change in Pain medication intakeBefore each cream is first applied, 7 days later, and for mannitol cream 1,2 and 3,months

Number of pills taken for pain in one day. Will decrease as the pain intensity decreases. Write the number of tablets that you took: 1. Tylenol/acetaminophen______, 2. Anti-inflammatory medication like Advil/ibuprofen, naproxen, diclofenac, Voltaren, Aleve______, 3. Tylenol or ASA (acetylsalicylic acid) plus narcotic like Tylenol 3, or 292 or Tramacet (acetaminophen/tramadol) ______, 4. Narcotic like morphine, hydromorphone/dilaudid, fentanyl, Demerol, tramadol______, 5. Cannabis, marijuana, or pot______, The total in each category will be added to calculate the total number of tablets taken in 24 hours.

Change in Alcohol intakeBefore each cream is first applied, 7 days later, and for mannitol cream 1,2 and 3 months

Number of alcoholic drinks in one day. May decrease as the pain intensity decreases. Write down the total number of alcoholic drinks you had in the last 24 hours:how many glasses of wine ______ glasses of hard liquor______ bottles of beer______. The total number of glasses will be recorded.

Change in questions from the brief pain inventory scoreBefore each cream is first applied, 7 days later, and for mannitol cream 1,2 and 3 months

The total from the following questions will be recorded to measure how much their pain is interfering with their lives: Circle one number. In the last 24 hours, how much has your pain interfered with your:

General activity:, Mood: Walking ability: Normal work: (includes both work outside the home and housework) Relations with other people: Sleep: Enjoyment of life: Each of these will be scored as follows: does not interfere 0 1 2 3 4 5 6 7 8 9 10 completely interferes. The scores added up. This sum should decrease as the pain decreases.

Change in PHQ-9 (Personal health questionnaire, 9 questions) ScoreBefore each cream is first applied, 7 days later, and for mannitol cream 1,2 and 3 months

Patients will fill the PHQ - 9 score. http://phqscreeners.com/pdfs/02_PHQ-9/English.pdf The sum of the answers from this questionnaire, which is used to measure the degree of depression, may decrease as the pain intensity decreases.

Change in Method of cream applicationwhen each cream is first applied, 7 days later, and for mannitol cream 1,2 and 3 months

Patients will describe whether they use cling wrap (4), gentle applicator (3) or rubbing in gently (2) or vigourous rubbing (1)

Change in effect and side effects of the creamDaily for the 14 days, of the crossover study, then at 1,2 and 3 months

How many times did you apply the cream today?_______ Circle one number. How bad was your pain?.. Before you applied the cream? NRS 0-10 1hour after you applied the cream? NRS 0-10 Did the cream relieve your pain? No □ if Yes □ in how many minutes?____ For how many hours was your pain relieved?____ Did you experience a side effect from the cream? No □ if Yes □ What was it?_________________ Any comments?_______________________

Trial Locations

Locations (1)

Dr. Helene Bertrand Inc.

🇨🇦

North Vancouver, British Columbia, Canada

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