AI-Powered Research

Current inclusion criteria as of 18/01/2008:
1. Ambulatory, otherwise healthy, men and women with neuropathic pain of at least three months duration which is due to trauma or surgery, with clinical evidence of allodynia or hyperalgesia
2. Average weekly pain intensity score less than or equal to 4 on a 10 cm visual analogue scale (anchors: 0 is no pain, 10 is worst pain ever)
3. Stable analgesic regimen (no anticipated change in therapy over the next two months)
4. No cannabis use in the past month
5. Ability to comply with smoking procedure
6. 18 years and older
7. Ability to attend research centre twice weekly for four weeks over a two month period, and to be able to be contacted by telephone during the study period
8. Normal liver (aspartate aminotransferase [AST] less than 3 x normal) and renal function (serum creatinine less than 133 µmol/l)
9. Haematocrit greater than 35%
10. Negative serum beta human chorionic gonadotrophin [ßhCG] pregnancy test
11. Women of childbearing potential should use adequate contraception during study and for three months after study
12. Proficient in English or French
13. Willing and able to give written informed consent

Previous inclusion criteria:
1. Ambulatory, otherwise healthy, men and women with neuropathic pain of at least three months duration which is due to trauma or surgery, with clinical evidence of allodynia or hyperalgesia
2. Average weekly pain intensity score 5= on a 10 cm visual analogue scale (anchors: 0 is no pain, 10 is worst pain ever)
3. Stable analgesic regimen (no anticipated change in therapy over the next two months)
4. No cannabis use in the past month
5. Ability to comply with smoking procedure
6. 18 years and older
7. Ability to attend research centre twice weekly for four weeks over a two month period, and to be able to be contacted by telephone during the study period
8. Normal liver (aspartate aminotransferase [AST] <3 x normal) and renal function (serum creatinine <133 µmol/l)
9. Haematocrit >38%
10. Negative serum beta human chorionic gonadotrophin [ßhCG] pregnancy test
11. Women of childbearing potential should use adequate contraception during study and for three months after study
12. Proficient in English or French
13. Willing and able to give written informed consent

Exclusion Criteria

Current exclusion criteria as of 18/01/2008:
1. Positive results of cannabinoid screening
2. Pain due to cancer or nociceptive causes (e.g. acute trauma, herpes zoster)
3. Unstable heart disease such as arrhythmias, cardiac failure, ischaemic heart disease, hypertension
4. Current substance abuse/dependence (including cannabis) as defined by the Diagnostic and Statistical Manual of mental disorders fourth edition (DSM IV) criteria
5. Unstable or untreated lung disease (tuberculosis [TB], asthma, carcinoma, chronic obstructive pulmonary disease [COPD])
6. History of uncontrolled psychotic disorder in the past year (for example, schizophrenia or bipolar disorder)
7. Current suicidal ideation, as assessed by clinical psychologist
8. Pregnancy and/or breast-feeding
9. Participation in other clinical trial in the 30 days prior to enrolment
10. Ongoing medical insurance or compensation claims (may confound subjective pain intensity ratings if pain has possible secondary gain)

Previous exclusion criteria:
1. Positive results of cannabinoid screening
2. Pain due to cancer or nociceptive causes (e.g. acute trauma, herpes zoster)
3. Cardiac arrhythmias, cardiac failure, ischaemic heart disease
4. Current substance abuse/dependence (including cannabis) as defined by the Diagnostic and Statistical Manual of mental disorders fourth edition (DSM IV) criteria
5. Pulmonary complications (tuberculosis [TB], asthma, carcinoma, chronic obstructive pulmonary disease [COPD])
6. History of psychotic disorder (for example, schizophrenia or bipolar disorder)
7. Current suicidal ideation, as assessed by clinical psychologist
8. Pregnancy and/or breast-feeding
9. Participation in other clinical trial in the 30 days prior to enrolment
10. Ongoing medical insurance or compensation claims (may confound subjective pain intensity ratings if pain has possible secondary gain)

Study & Design

Study Type: Interventional

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
1. Average pain intensity measured daily during each cycle by 100 mm visual analogue scale (VAS)<br>2. No pain and worst pain possible will be used as anchors in the 11-item numerical rating scale. The daily pain intensity score will be averaged across all study days for each cycle to comprise the main outcome variable.

Secondary Outcome Measures