Abstract
Despite the major benefits of antiretroviral therapy on survival during HIV infection, there is an increasing need to manage symptoms and side effects during long-term drug therapy. Cannabis has been reported anecdotally as being beneficial for a number of common symptoms and complications in HIV infections, for example, poor appetite and neuropathy. This study aimed to investigate symptom management with cannabis. Following Ethics Committee approval, HIV-positive individuals attending a large clinic were recruited into an anonymous cross-sectional questionnaire study. Up to one-third (27%, 143/523) reported using cannabis for treating symptoms. Patients reported improved appetite (97%), muscle pain (94%), nausea (93%), anxiety (93%), nerve pain (90%), depression (86%), and paresthesia (85%). Many cannabis users (47%) reported associated memory deterioration. Symptom control using cannabis is widespread in HIV outpatients. A large number of patients reported that cannabis improved symptom control.
Key Words
Introduction
HIV or AIDS affects over 40 million people in the world
1
and more than 49,500 in the UK.UNAIDS. Joint United Nations Programme on HIV and AIDS 2003. Available at www.unaids.org/en/resources/epidemiology.asp.
2
Although there is still no cure available for this disease, remarkable improvements in the survival of HIV-infected individuals have been achieved.ONS, Office of National Statistics. HIV infections: By year of diagnosis and route of transmission 2002. Available at www.statistics.gov.uk/cci/nugget.asp?id=654.
3
This survival has lead to an increasing prevalence of individuals with HIV infection, many on long-term treatment with combinations of antiretroviral therapies. This has increased the clinical focus on the management of chronic symptoms associated with both HIV and the side effects of antiretroviral medication. Recently, in small sample studies of HIV patients, the medicinal use of cannabis has been documented as a treatment for varied symptoms.4
, 5
, 6
, 7
Symptoms associated with HIV occur as both direct and indirect consequences of the disease process and as a side effect of the antiretroviral drugs used in the treatment of the disease. These symptoms include nausea and vomiting, pain (e.g., in a nerve distribution), reduced appetite, weight loss, headaches, diarrhea, constipation, anxiety, and depression. Flu-like symptoms and severe myalgia can result directly from seroconversion early in the disease. Central pain and peripheral neuropathy can occur as a result of viral-mediated neurotoxicity, secondary to either mitochondrial damage, demyelination, or low B12 levels, all of which have been observed in patients with HIV. The inflammation that occurs as a result of the mitochondrial damage can result in HIV-related encephalopathy or HIV-related colitis. Symptoms may also occur secondary to infections or tumors, which have resulted from HIV-related immunosuppression. Examples of this include nausea and dysphagia from esophageal candida, or pain from a gastrointestinal lymphoma. Symptoms commonly occurring as a side effect of HIV treatment include renal colic from nephrolithiasis associated with the protease inhibitor, indinavir; painful peripheral neuropathy from use of stavudine, a nucleoside analogue; or sleep disturbances from the non-nucleoside inhibitor, efavirenz. Thus, a wide range of symptoms can significantly affect the quality of life of individuals living with HIV as a long-term chronic infection.
8
, 9
It has been recognized that cannabinoids such as delta-9-tetrahydrocannabinol (THC), which is now available as a licensed pharmaceutical preparation, can improve appetite and relieve nausea and vomiting.
10
Cannabis plant material not only contains THC but also other cannabinoids, such as cannabidiol (CBD), that may mitigate psychotic mood effects of THC.11
The aim of this study was to measure the patterns and prevalence of cannabis use in patients presenting at a large HIV clinic and to evaluate its beneficial or detrimental effect on symptom control.
Methods
Subjects
Following Ethics Committee approval, HIV-positive patients were recruited into an anonymous cross-sectional questionnaire survey using a single center. The outpatient clinic provided a walk-in service as well as pre-arranged appointments, including pharmacy and phlebotomy sections. All patients entering the clinic were asked to verbally consent to participate in the study. Written consent was not obtained in order to protect patient anonymity. The number of patients who refused to take part was recorded. Many patients were regular clinic users, had discussed their symptoms with HIV and pain specialists, and were able to distinguish between the various types of pain described on the questionnaire. A researcher was available to answer questions (e.g., on the interpretation of words). Patients completed the questionnaire while waiting and confidentiality was maintained by enumerating the papers without patient identification.
Questionnaire
The questionnaire was piloted to refine its content, word use, and format and then issued to patients attending the clinic. The questionnaire (see Appendix) was designed to contain close-ended questions with defined yes/no or categorical responses. It was divided into sections. The first included demographics (age, sex, number of years with HIV) and a validated scale to measure degree of disability described by Sharrack and Hughes.
12
The second had specific questions concerning the patient's use of cannabis medically to treat symptoms of HIV. These symptoms included those directly related to HIV plus those resulting from their medication. Those who did not use cannabis for medicinal purposes, including those who used it solely for recreation, were not required to continue completing the questionnaire, although their demographic details were recorded. The next section included questions relating to frequency, patterns, and reasons for cannabis use. Then in tabular form, a range of symptoms were listed (Table 1), and against each one, the patient was invited to score benefit or detriment as ‘much better,’ ‘little better,’ ‘unchanged,’ ‘a little worse,’ and ‘much worse’. For the symptoms of pain and sensory changes, the questionnaire also contained ‘body diagrams’, that is, pain maps, so that the patients could mark where they identified their nerve or muscle pain, tingling and numbness.Table 1Order of Symptom List in Questionnaire as Scored by Patients for Benefit or Detriment
| Lack of appetite |
| Feeling sick (i.e., nausea) |
| Tremor |
| Depression |
| Anxiety |
| Weight loss |
| Weakness |
| Tiredness |
| Vision dimness |
| Slurred speech |
| Memory loss |
| Constipation |
| Headaches |
| Diarrhea |
| Pain in muscles |
| Nerve pain |
| Tingling |
| Numbness |
Analysis
Data from the questionnaires were entered into an Access database (Windows 98 version) and analyzed using the Statistical Package for Social Sciences (SPSS 11.5, SPSS Inc., Chicago). Categorical data comparing the sex differences between the two groups and symptom severity were analyzed using the Fisher's exact test. Because the distribution of age and the number of years with HIV were not normal and had some outliers, the differences in these variables between the two groups were analyzed using the Mann-Whitney U test. Both simple frequency analysis and the sign test were used in assessing the percentage improvement or deterioration in symptoms.
Results
A total of 523 questionnaires were completed from 565 patients approached. This was a 93% response rate. Of those who completed the study, 143 (27%) used cannabis to treat symptoms associated with HIV.
Physical Data
The sex, age, years with HIV, disability, and cannabis user status are shown in Table 2, Table 3. About 1 in 10 patients were female and few were severely disabled in this outpatient setting. Compared with females, males were statistically significantly likely to be cannabis users (P < 0.01) and those who had the disease for longer and were more disabled were also more likely to be users (P < 0.01).
Table 2Demographic Data, Disability Scores, and the Number of Patients Using Cannabis to Treat Symptoms
| Females n = 43 (8%) | Males n = 480 (92%) | All Subjects n = 523 | |
|---|---|---|---|
| Age (years) | 38 [32–43] (20–65) | 39 [35–44] (20–69) | 39 [35–44] (20–69) |
| Years with HIV | 6 [2–9] (0–18) | 9 [4–13] (0–25) | 8 [4–13] (0–25) |
| Disability | |||
| 0 | 12 (28%) | 164 (34%) | 176 (34%) |
| 1 | 14 (33%) | 136 (28%) | 150 (29%) |
| 2 | 10 (23%) | 100 (21%) | 110 (21%) |
| 3 | 4 (9%) | 74 (15%) | 78 (15%) |
| 4 | 3 (7%) | 5 (1%) | 8 (2%) |
| 5 | 0 | 1 (0.2%) | 1 (0.2%) |
| Number that used cannabis to treat symptoms | 4/43 (9%) | 139/480 (29%) | 143/523 (27%) |
a Median [IQR] (range).
b 0 = none; 1 = mild; 2 = moderate not requiring help from others; 3 = moderate requiring help from others; 4 = severe with almost total loss of function; and 5 = total loss of function.
Table 3Demographic Differences Between Users and Non-Users of Cannabis for Symptom Control
| Users n = 143 | Non-Users n = 380 | Statistical Significance | |
|---|---|---|---|
| Males:Females | 139:4 | 341:39 | P < 0.01 |
| Age | 40 [36–44] (26–61) | 38 [34–44] (20–69) | P = 0.046 |
| Years with HIV | 10 [6–15] (0–25) | 7 [3–12] (0–20) | P < 0.01 |
| No disability:Disability | 17:126 | 159:221 | P < 0.01 |
a Median [IQR] (range).
When nerve pain was reported on the pain map, it was experienced mainly in the legs, and less in the feet and hands (27, 19, and 15 patients, respectively). Muscle pain was predominantly localized to the legs, but also to the lower back, shoulders and neck (46, 19, and 19 patients, respectively). Tingling and numbness was experienced in the periphery, with the hands and feet being affected (34 and 26 patients, respectively).
Patient Choice of Route and Timing for Symptom Control
Of the 143 patients who had used cannabis to treat HIV symptoms, 107 (75%) were current users. Within the whole group, smoking was the single route of administration in 101 (71%), and was combined with eating and drinking the plant in 39 (27%); ingestion was the only route in 3 (2%). On a day that cannabis was used, 50 patients (36%) would take it once, 33 (23%) twice, 23 (16%) three times, and 35 (24%) four or more times. Most patients (79/143 [55%]) were daily users and 15 (11%) used it weekly. Others reported intermittent administration during the week. Thus, all patients reported using cannabis at least once a week to relieve symptoms.
Throughout the day, the majority of patients (91/143 [64%]) took cannabis after 6 p.m. and before midnight. However, an overlapping group (66/143 [46%]) also reported use at any time if necessary. The reasons for taking the cannabis at these times were reported in a structured format, as detailed in Table 4. A number of reasons related to the time of administration, not least of which was recreational use together with medicinal use. Relief of symptoms of anxiety and depression was common, as was general symptom relief. The reported use for relaxation may reflect the time at which it was taken, namely, during the evening.
Table 4Reasons for Using Cannabis
| Purpose | n | % |
|---|---|---|
| Treat symptoms | 77 | 54 |
| Aid relaxation | 121 | 85 |
| Reduce anxiety | 94 | 66 |
| Relieve depression | 75 | 52 |
| Reduce symptom frequency | 29 | 20 |
| Increase energy levels | 15 | 11 |
| For a ‘high’ | 62 | 43 |
Effect on Symptoms
A lack of appetite was the most frequent symptom reported (Table 5) and 97% experienced improvement with cannabis use. Pain was the next most frequent, being present in 45% of patients and improved in 94% of them. The collective results demonstrated statistically significant improvement in half or more patients in symptoms of nausea, anxiety, nerve pain, depression, tingling, numbness, weight loss, headaches, tremor, constipation, and tiredness. Symptoms that were not improved included weakness and slurred speech, and statistically significant memory deterioration was recorded in 47% of users.
Table 5Effect of Cannabis on Complaint of Symptoms in 143 HIV Patients
| % Responding | |||||||
|---|---|---|---|---|---|---|---|
| Symptom | Number of Complaints | Much Better | Little Better | No Change | Little Worse | Much Worse | P-value |
| Lack of appetite | 111 | 79 | 18 | 2 | 0 | 1 | 0.000 |
| Pain in muscles | 65 | 63 | 31 | 6 | 0 | 0 | 0.000 |
| Nausea | 62 | 56 | 37 | 3 | 2 | 2 | 0.000 |
| Anxiety | 98 | 64 | 29 | 3 | 2 | 2 | 0.000 |
| Nerve pain | 53 | 51 | 40 | 9 | 0 | 0 | 0.000 |
| Depression | 94 | 56 | 30 | 9 | 4 | 1 | 0.000 |
| Tingling | 46 | 37 | 48 | 9 | 7 | 0 | 0.000 |
| Numbness | 42 | 36 | 36 | 24 | 5 | 0 | 0.000 |
| Weight loss | 62 | 45 | 24 | 31 | 0 | 0 | 0.000 |
| Headaches | 46 | 35 | 30 | 33 | 2 | 0 | 0.000 |
| Tremor | 24 | 37 | 29 | 21 | 13 | 0 | 0.004 |
| Constipation | 24 | 21 | 29 | 46 | 4 | 0 | 0.003 |
| Tiredness | 60 | 17 | 33 | 33 | 15 | 2 | 0.002 |
| Diarrhea | 48 | 13 | 23 | 56 | 6 | 2 | 0.007 |
| Vision dimness | 22 | 9 | 27 | 55 | 9 | 0 | 0.109 |
| Weakness | 48 | 10 | 21 | 54 | 15 | 0 | 0.134 |
| Memory loss | 38 | 13 | 5 | 34 | 34 | 13 | 0.043 |
| Slurred speech | 9 | 11 | 0 | 78 | 11 | 0 | 1.00 |
Note: In ranked order of those demonstrating improvement (recorded as % much better, little better) in comparison to those recorded with no change, little worse, or much worse. The P-value in the last column is the exact 2-sided P-value for the sign test of no change.
Discussion
The demographic characteristics of our cohort of patients (male:female, 11.2:1) is comparable with the UK population of HIV-positive patients, which has a male:female ratio of 11.5:1. In addition, their ages and duration of HIV disease were comparable with the general UK data for such patients.
13
Our sample of 523 patients has the highest response rate and is the largest study of its kind. It compares with previous studies, which have had samples ranging from 72 subjectsPublic Health Laboratory Report Feb 2003. Available at www.hpa.org.uk/infections/topics_az/hiv_and_sti/hiv/hiv.htm
7
to 442.6
This detailed report of cannabis use for symptom control in a clinically significantly large group of patients can form the basis for more extensive investigations using purified and standardized cannabis extracts.Despite the fact that cannabis is still illegal, its use for medical purposes appears to be quite widespread. A report from the British Medical Association
14
stated “many normally law abiding citizens—probably many thousands in the developed world” use cannabis illegally for therapy. Wesner15
reported from an anonymous mail survey of 123 HIV-positive patients in Honolulu that 36.9% of them used cannabis for therapeutic reasons. Approximately one-quarter of 228 HIV-positive men in the Sydney Men and Sexual Health study reported therapeutic use of cannabis.Wesner B. The medical marijuana issue among PWAs: Reports of therapeutic use and attitudes towards legal reform. Working Paper No. 3, Working Paper series. Drug Research Unit, Social Science Research Institute, University of Hawaii. Available at http://www.drugpolicy.org/library/mmwesne.cfm. Accessed June 1996.
16
Thirty-two percent (32%) of 72 patients at a clinic in Alabama reported the medical use of marijuana.7
These results are comparable to a more recent study carried out in Northern California, in which 33.3% of HIV-positive patients who responded to an anonymous mailed questionnaire used cannabis to treat symptoms associated with their disease.6
Our study expanded these findings in a large city clinic population by focusing on the patient's perceived improvement or worsening of symptoms for which cannabis was considered the origin.The large number of patients using cannabis as medicinal therapy for symptoms related to HIV raises a number of issues. First, patients are being left with no alternative but to use a non-medical source of supply, which has the potential for heterogeneity of active cannabinoids, toxic contaminants, inappropriate dose, and drug misuse. Second, if part of the plant material has therapeutic efficacy, the source of this material should be standardized and subjected to clinical trials so that safe and effective use is advocated. Third, the patient is unlikely to divulge cannabis use to their medical team, so that potential drug interactions with prescribed antiretroviral medications may be occurring. In addition, in this study, the number of purely recreational users was not determined so that the overall incidence of drug interactions may be far greater. The type of drug interactions to be considered include loss of cognitive function because it is well-recognized that this is an effect of both cannabis
17
and antiretroviral drugs such as efavirenz.18
Certainly, the loss of memory reported by these patients is of clinical significance, particularly in the methodological design of clinical trials, and if it is the result of combining preparations, this may be investigated using known standardized cannabinoid therapies. This approach may be one way to reduce additive effects and prevent patients being subject to the effects of unpredictable concentrations of illicit drugs.The positive responses to symptom control recorded in this study, as exemplified in Table 5, suggest that it is highly probable that cannabinoid medications have a medicinal role in this condition for a number of reasons. First, they are reported by patients to improve appetite, reduce weight loss, and alleviate nausea.
19
, 20
, 21
, 22
, 23
These effects have been recognized and synthetic THC (dronabinol) is licensed for use in the U.S. for this indication. However, no direct comparison has been attempted with a cannabis plant extract that will contain not only THC but also other cannabinoids, of which CBD is reputed to reduce the adverse effects of THC.24
Secondly, pain relief appears to be significant in cannabis users, thereby suggesting a potential target for investigation in the use of cannabinoids as analgesics in HIV patients.Patients have reported various forms of pain with HIV, such as muscular and neuropathic pain, and these were characterized in the pain maps drawn by the patients. Currently available analgesic drugs have limited efficacy, particularly for neuropathic pain.
25
Clearly, there is a need to develop alternative analgesic agents, such as cannabinoids, to improve the choice of therapies. There is animal evidence that cannabinoids have analgesic effects that operate in models of hyperalgesia and allodynia, both indicators of neuropathic pain states,26
, 27
and the discovery of the endogenous cannabinoid system has led scientists to explore the role of endocannabinoids in chronic pain models.28
, 29
However, in clinical practice the choice of natural or synthetic phyto- or endo-cannabinoids for clinical trials is very limited. There have been several anecdotal and clinical trial reports that cannabis plant extract and synthetic THC and related analogues produce pain relief in humans.30
, 31
, 32
, 33
For this present select group of HIV patients, given the reported symptoms experienced using cannabis plant material, there is a strong concern from the medical community managing these patients to limit adverse side effects from self-administered drugs and to provide cannabinoids in a formulation and dosing schedule that avoids harm to the patient. For example, there is strong evidence that the smoking route of administration of cannabis is not safe long-term because of the carcinogenic properties of a cannabis cigarette.34
A pattern of cannabis use emerges from this study that is regular, ongoing, and treats the symptoms of HIV patients to their satisfaction. Given the sedative properties of cannabis, it is important to assess whether evening dosing for cannabinoid therapies is more useful or appropriate. Its sedative effects may be helpful at this time but none were reported as predominant. Presumably there is tolerance to these types of effects.
29
More importantly, reduction of pain, anxiety, and gastrointestinal upset appears to be the constellation of symptom control sought by these HIV patients, as shown in Table 4, Table 5.In relation to HIV, there have been anecdotal reports of patients who were already recreational users of cannabis reporting that it improved certain symptoms, such as loss of appetite and nausea, as well as pain and general well being. A small, uncontrolled study of 10 symptomatic AIDS patients reported that dronabinol might be effective in reducing nausea and increasing appetite.
10
Where patients are also medicating with antiretroviral agents, the combination of cannabis and protease inhibitors may be detrimental by altering viral loads. Thus, the effect of smoking on the viral load of HIV-infected patients was investigated by a short-term randomized placebo controlled trial.36
No adverse effects of either therapy were measured with respect to RNA levels, CD4+ and CD8+ cell counts, or protease inhibitor levels. This brief trial suggests that there are no obvious harmful effects, but these need to be determined using an appropriate route of drug administration and a longer-term study.There is accumulating evidence that suggests that cannabinoids have therapeutic applications in a variety of neurodegenerative diseases, such as multiple sclerosis,
37
, 38
Huntington's disease,39
and brain injury.40
So far, in terms of HIV, the evidence for therapeutic efficacy of cannabinoids is still mainly anecdotal. We have sought to establish if an improvement from cannabis use, albeit self-administered and not standardized, is seen in symptoms such as pain, appetite, and nausea in a large sample of HIV patients. To do this, we expanded on previous research by determining specifically the variety and groups of symptoms that patients select to modify by their use of cannabis. We also secured a therapeutic timetable in order to predict the frequency of drug administration for the patient's selected symptoms. These results will be important in the design of a randomized, placebo-controlled clinical trial comparing conventional treatments to cannabis for symptoms of HIV.Acknowledgments
The authors thank Dr. Elena Kulinskaya for statistical advice and Dr. Sarah Cox, Dr. Andrew Rice, and the staff at the Kobler Clinic, St. Stephen's Center.
Appendix. Questionnaire
HIV Symptoms and the Use of Cannabis
This questionnaire is designed to establish the current use of cannabis for the management of symptoms from HIV in our patients. We would be grateful for some personal details (but not details of identification) and your past and present experiences (if any) with cannabis.
Please complete the following:
General Details:
- Sex: MALE/FEMALE (encircle as necessary)
- Age: ………years
- Number of years with HIV: ………….
Degree of Disability
- Please choose ONE of the following statements which best describes how severely you are affected by the HIV disease, and how it affects your activities of daily living:
- None
- Mild symptoms
- Moderate symptoms—not requiring help from others
- Moderate symptoms—requiring help from others
- Severe symptoms—almost total loss of function
- Total loss of function
Cannabis use
Have you ever used cannabis to relieve your symptoms (as listed below) of HIV? Y/N
If “NO” we thank you for answering this questionnaire and you are not required to complete any more of the questionnaire.
If “YES” please complete the following details:
How do you take the cannabis?
- Smoke Y/N
- Drink Y/N
- Eat Y/N
- Other (state)…………………….
How many years have you used cannabis relieve some of your symptoms?………..years
How many times a day do you use cannabis?……………
How many days a week do you take cannabis?………….
When do you take cannabis: [Please choose only ONE]
- After 6 pm and before midnight Y/N
- Between 6 am and midday Y/N
- Midday to 6 pm Y/N
- At any time when necessary Y/N
- Just before going to bed Y/N
- At regular intervals during the day Y/N
Do you take cannabis to: [You may choose MORE THAN ONE]
- Relieve symptoms Y/N
- Aid relaxation Y/N
- Relieve anxiety Y/N
- Relieve depression Y/N
- Reduce symptom frequency Y/N
- Obtain energy Y/N
- To get a ‘high’ / Recreational Y/N
For each symptom in the left-hand column state if the symptom is now present. Then mark for each symptom, whether past or present, its response to cannabis use, i.e., better or worse.
Diagrams are provided below for the question relating to sites of pain, etc.
Tabled
1
| Present | Response to cannabis [Please tick ONE box] | |||||
|---|---|---|---|---|---|---|
| Symptom (past or present) | Y/N | Much better | Little better | Not changed | Little worse | Much worse |
| Lack of appetite | ||||||
| Feeling sick, i.e., Nausea | ||||||
| Anxiety | ||||||
| Depression | ||||||
| Tremor | ||||||
| Headaches | ||||||
| Weight loss | ||||||
| Weakness | ||||||
| Tiredness | ||||||
| Vision dimness | ||||||
| Slurred speech | ||||||
| Tremor | ||||||
| Memory loss | ||||||
| Constipation | ||||||
| Diarrhea | ||||||
| Muscle pain (please mark on Diagram 1 where you are affected by this) | ||||||
| Nerve pain (please mark on Diagram 2 where in your body this is) | ||||||
| Tingling (draw on Diagram 3 where this is) | ||||||
| Numbness (draw on Diagram 4 where this is) | ||||||
| Others (please state) | ||||||
N.B. Please do not forget to fill in the body diagrams on the next page if you suffer from MUSCLE PAIN, NERVE PAIN, TINGLING OR NUMBNESS.
Once completed please hand over this questionnaire to the reception desk.
THANK YOU.
References
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ONS, Office of National Statistics. HIV infections: By year of diagnosis and route of transmission 2002. Available at www.statistics.gov.uk/cci/nugget.asp?id=654.
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Public Health Laboratory Report Feb 2003. Available at www.hpa.org.uk/infections/topics_az/hiv_and_sti/hiv/hiv.htm
- Therapeutic uses of cannabis, British Medical Association.Harwood Academic Publishers, The Netherlands1997 (p. 77)
Wesner B. The medical marijuana issue among PWAs: Reports of therapeutic use and attitudes towards legal reform. Working Paper No. 3, Working Paper series. Drug Research Unit, Social Science Research Institute, University of Hawaii. Available at http://www.drugpolicy.org/library/mmwesne.cfm. Accessed June 1996.
Prestage GS, Kippax S, Grulich A. Use of treatments and health enhancement behaviours among HIV positive men in a cohort of homosexually active men. XI International Conference on AIDS, Vancouver, BC, Canada, July 1996. Abstract thD 5181.
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- Short-term effects of cannabinoids in patients with HIV-1 infection.Ann Intern Med. 2003; 139: 258-266
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Article info
Publication history
Accepted:
July 28,
2004
Identification
Copyright
© 2005 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc.
