Effect of intravenous administration of paracetamol on morphine consumption in cancer pain control.

OBJECTIVE: The present study aimed to examine the effectiveness of intravenous administration of paracetamol added to morphine in the control of cancer pain and its possible contribution as reduction of opioid consumption and opioid-related side effects. MATERIALS AND METHODS: A total of 43 patients with chronic cancer pain without neuropathic origin aged between 18 and 76 years and receiving step 2 treatment according to the World Health Organization analgesic ladder were included. Patients were randomized to receive intravenous administration of saline (control) or 1 g of paracetamol on top of morphine. Visual analog scale (VAS), patient rating index (PRI), Eastern Cooperative Oncology Group (ECOG) status, patient satisfaction, and safety were evaluated. MAIN RESULTS: Both treatments resulted in improved VAS and PRI scores compared to baseline. However, groups did not differ in terms of VAS and PRI scores, morphine consumption, side-effect frequencies, laboratory values, ECOG status, and patient satisfaction. CONCLUSIONS: Although safe and there are signals for a true analgesic efficacy, our results failed to confirm any benefits of add-on treatment with intravenous administration of paracetamol. However, the study was underpowered, and future studies in this important area need to be wary of background noise and the risk of a type II error.

Gabapentin and an opioid combination versus opioid alone for the management of neuropathic cancer pain: a randomized open trial.

Neuropathic cancer pain represents a major challenge. Treatment often requires adjuvant analgesics, including gabapentin, to complement the effects of opioids. This study aimed to compare the effectiveness and safety of gabapentin combined with an opioid versus opioid monotherapy for the management of neuropathic cancer pain. Seventy-five cancer patients who were receiving opioid therapy and reported sufficient pain relief of nociceptive, but not neuropathic, pain were enrolled. Sixty-three patients completed the study. Patients were randomized to one of the following treatment protocols: 1) gabapentin adjuvant to ongoing opioid treatment titrated according to pain response while opioid dose was kept constant (group GO), and 2) continuation of opioid monotherapy according to the World Health Organization treatment ladder approach (group OO). Changes in pain intensity, allodynia, and analgesic drug consumption were evaluated at Day 4 and Day 13. Side effects were also recorded. Both treatments resulted in a significant reduction of pain intensity at Day 4 and Day 13 compared to baseline. However, mean pain intensity for burning and shooting pain was significantly higher in the OO group compared to the GO group at both the fourth (P=0.0001) and 13th (P=0.0001) days of the study. An earlier significant decrease (at Day 4, P=0.002) was observed for allodynia in the GO group compared to the OO group. The rate of side effects in the GO group was significantly lower than that in the OO group (P=0.015). These data suggest that gabapentin added to an opioid provides better relief of neuropathic pain in cancer patients than opioid monotherapy; this combination of gabapentin and an opioid may represent a potential first-line regimen for the management of pain in these patients.

[Comparison of efficacy of gabapentin and amitriptyline in the management of peripheral neuropathic pain]. / Periferik nöropatik agrinin kontrolünde gabapentin ve amitriptilinin etkinliginin karsilastirilmasi.

In this single center, double blind and randomized trial gabapentin as a new anticonvulsant was compared in efficacy and safety with amitriptyline which is a classic agent in neuropathic pain treatment. Fourty six patients with neuropathic pain which was burning, stabbing and shooting in quality were allocated to take gabapentin (group GBP) and amitriptyline (group AMI) monotherapy. The assesment variables were burning, stabbing, shooting pain on visual analog scale (VAS; 0: no pain, 10: worst pain imaginable), allodynia as present or not by lightly touching the skin with cotton. Primary efficacy variable was the degree of burning, stabbing and shooting pain improvement that was accepted as the difference of beginning and 4th week's VAS of all pain qualities. The secondary efficacy variable was the patient satisfaction scale determined as whether possible side effects of study drugs affect the patients' daily life. The degree of pain improvement was only seen in shooting pain and was statistically significantly high in group GBP. The patient satisfaction scale was also high in group GBP. Both gabapentin and amitriptyline provided effective pain control in peripheral neuropathic pain. Additionally gabapentin was more effective especially in paroxysmal shooting pain than other pain qualities. And also gabapentin was tolerated well.