Hoang, B.X., Tran, D.M., Tran, H.Q., Nguyen, P.T., Pham, T.D., Dang, H.V., … Shaw, D.G. (2011). Dimethyl sulfoxide and sodium bicarbonate in the treatment of refractory cancer pain. Journal of Pain & Palliative Care Pharmacotherapy, 25, 19–24.

To evaluate efficacy and effective doses of a dimethyl sulfoxide (DMSO) sodium bicarbonate combination for refractory pain in patients with cancer

Participants received 8 infusion cycles of 20–60 ml of DMSO mixed with 1.4% of NaHCO3 daily for 10 days with 2 days off between cycles. Data were recorded at baseline, and at 3, 10, 20, 30, 60, and 96 days. Patients were allowed to take any medication, supplements, or herbal preparations as usual for them. The DMSO concentration was increased incrementally until pain was completely under control.

• The study reported on 26 patients.
• The mean age was 56.8 years, with a range of 17–72 years.
• The sample was 38% female and 62% male.
• All patients had life expectancies of six months or less.
• A variety of cancer types were included, with primary liver, lung, and colorectal cancers the most prevalent.

The study was conducted at a single-site, inpatient setting in Hanoi, Vietnam.

This was an open label, prospective trial.

Patients used a verbal pain scale ranging from 0 (no pain) to 4 (extreme pain).

After 2 cycles, 11 (43%) patients achieved 20% or more reduction in pain and were discharged from the hospital to outpatient therapy. After 3 cycles, an additional 23% achieved this level of pain control. All but 4 patients achieved pain control at this level by day 96. By day 96, 83% of patients used less pain medication. No major negative effects occurred related to the infusion solution. The most frequent side effects were headache and chills during and after treatment. These effects resolved within 2 hours. The proportion of patients with other symptoms also was reported to decline over the course of the study.

This preliminary information suggests that this DMSO and NaHCO3 infusion can have a positive benefit for patients in the relief of refractory pain and is not associated with severe adverse effects.

• The sample size was small, with fewer than 30 patients.
• This was an open-label design with no control or comparison group.
• The single measurement method for pain did not have established reliability and is a rather gross measure to use in defining complete pain control.
• The authors reported a decline in the prevalence of other symptoms, but they did not provide information on how these were measured or how symptom absence was determined.

Findings suggest that this DMSO infusion may be a safe alternative for pain control in terminal patients with severe pain that is not otherwise well controlled. However, the study does not provide sufficient support for this intervention. The positive findings here suggest that further well-designed research on DMSO infusion is warranted.