E. Bruera et al., Twice-daily versus once-daily morphine sulphate controlled-release suppositories for the treatment of cancer pain - A randomized controlled trial, SUPP CARE C, 7(4), 1999, pp. 280-283
We evaluated the safety and efficacy of controlled-release morphine sulphat
e suppositories administered 12-hourly and once daily in patients with chro
nic cancer in a randomized double-blind crossover trial. Pain was assessed
using a 100-mm VAS pain scale and a five-point ordinal pain scale. The VAS
pain intensity score was 17.5 +/- 17.2 after suppositories every 12 h, vers
us 16.2 +/- 13.4 after suppositories every 24 h (difference not significant
). The difference between the mean VAS pain scores with 12-hourly and once-
daily dosing was 1.3 mm. (not significant). The mean ordinal pain scores we
re 11.0 +/- 0.7 versus 1.0 +/- 0.6 for 12-hourly and once-a-day dosing, res
pectively (not significant). A retrospective power analysis indicated that
a difference of 5.9 mm was detectable, even with only 6 patients. Adverse e
vents noted were constipation, nausea, anorexia, and dry mouth. The use of
once-a-day controlled-release morphine suppository is a more convenient and
equally effective alternative to twice a day dosing.