Caffeine as an adjuvant therapy to opioids in cancer pain: a randomized,
double-blind, placebo-controlled trial.
Author(s): Suh SY(1), Choi YS, Oh SC, Kim YS, Cho K, Bae WK, Lee JH, Seo AR, Ahn HY.
Affiliation(s): Author information:
(1)Department of Medicine, Dongguk University, Seoul, Korea; Department of Family
Medicine, Dongguk University Ilsan Hospital, Goyang-si, Gyeonggi-do, Korea.
Electronic address: lisasuhmd@hotmail.com.
Publication date & source: 2013, J Pain Symptom Manage. , 46(4):474-82
CONTEXT: Opioid therapy often shows insufficient efficacy and substantial adverse
events in patients with advanced cancer.
OBJECTIVES: To assess the efficacy of caffeine infusion as an adjuvant analgesic
to opioid therapy in patients with advanced cancer.
METHODS: A double-blind, randomized, placebo-controlled trial was conducted in
the palliative care wards of two teaching hospitals in South Korea. A total of 20
of 41 participants were assigned to the caffeine group and 21 to the placebo
group. The participants received caffeine (200mg) or normal saline intravenously
once a day for two days. The primary outcome was pain, which was measured using a
10-point rating scale. Other outcomes included drowsiness, confusion, nausea,
sleep disturbance, fatigue, and sadness.
RESULTS: Three participants (two in the caffeine group and one in the placebo
group) dropped out after the first intervention because of insomnia; thus, 38
participants completed the trial. Pain score was significantly lower in the
caffeine group than in the placebo group after the second trial (P=0.038). The
mean reduction in pain intensity in the caffeine group was 0.833 (95% confidence
interval [CI] 0.601-1.066), whereas that in the placebo group was 0.350 (95% CI
0.168-0.532). Considering an improvement higher than 30% from baseline as the
threshold value, drowsiness improved significantly in the caffeine group after
the first trial (P=0.041). Adverse event rate did not differ between the two
groups.
CONCLUSION: Caffeine infusion significantly reduced pain and drowsiness, but the
reduction did not reach clinical significance in patients with advanced cancer
undergoing opioid therapy. Further investigations are warranted.
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