Marijuana used to treat neuropathic pain in AIDs patients
Neuropathic pain occurs when damaged or dysfunctional nerve fibers send incorrect signals to pain centers leading to feelings of tingling, numbness, and shooting and burning pain. It’s very discomforting to the patient and difficult to treat.
Here’s a study where cannabis showed benefit.
Patients were randomly assigned to smoke cannabis (3.56% tetrahydrocannabinol) or placebo cigarettes without the cannabinoids for 5 days. Based on the responses of 50 patients who completed the study?
- Cannabis reduced daily pain by 34% vs 17% with placebo, a significant difference.
- Significantly greater than 30% reduction in pain was reported by 52% in the cannabis group vs 24% in the placebo group.
- The first cannabis cigarette reduced chronic pain by about 72% vs 15% with placebo.
- No adverse effects reported.
This sounds good, but a couple of questions come to mine.
The best-designed studies compare the effectiveness of treatments between “intent-to-treat” groups — all the patients who qualified and entered the study, regardless of whether they completed the study are evaluated. Patients who don’t complete the study are “treatment failures,” with explanation for why this occurred. This study only looks at results based on those who completed the study.
It’s easier to show significant benefits when you limit the evaluation to those who are able to finish treatment.
- Would the results have been significant if all patients had been evaluated?
- Was the non-existent level of side effects due to the fact that patients who could not tolerate marijuana never made it to the end of the study?
A group in San Francisco called the Community Consortium, Positive Health Program sponsored the study. The Consortium has access to a large population of AIDs patients.
That’s the good news.
The potential problem is that while these groups have access to large numbers of patients, they tend to be compromised when it comes to conducting the highest quality research.
The bottom line?
In patients who can tolerate the drug, cannabis can be expected to contribute to the short-term management of neuropathic pain associated with AIDs. The greatest effect occurs after the first dose and lasts up to 5 days.
2/20/07 10:03 JR
