Metamizol potentiates morphine antinociception but not constipation after chronic treatment

Synergistic interaction between tapentadol and flupirtine in the rat orafacial formalin test

“…Drugs that can be used in combination with opioids and other analgesics to enhance analgesic efficacy include norepinephrine transporter modulators, non-steroidal anti-inflammatory drugs (NSAIDs), local anesthetics, calcium channel blockers, cannabinoids, α 2 -adrenergic agonists and GABA B agonists (Smith, 2008). Many studies examining the combination of opioids and NSAIDs have been investigated in different animal models: tramadol with meloxicam in the sciatic nerve ligated rat model (Abass et al, 2014) as well as in the formalin test (Isiordia- Espinoza et al, 2011), morphine with metamizol in hind paw test ( ern nde - Delgadillo et al, 2002), tramadol with propacetamol in rats and mice (Zhang et al, 2011), buprenorphine with lumiracoxib in the rat orofacial formalin test (Capuano et al, 2009). Recently, an investigation on the combination between TAP and pregabalin has resulted in a synergistic antihypersensitive activity in neuropathic pain (Christoph et al, 2011).…”

Metamizole: A Review Profile of a Well-Known “Forgotten” Drug. Part I: Pharmaceutical and Nonclinical Profile

“…Analgesic potentiation has been reported for the combined administration of morphine and metamizole in different models of antinociception, including arthritic inflammation (48), the formalin test (1); the tail flick test (14,49), and the writhing reflex test (97). The synergy between opioids and nSAiDs could be related to endogenous opioid release and different pathways of pain transmission, probably related to the different intracellular signal transduction mechanisms of action of opioid and non-opioid agents (69).…”

“…In particular, metamizole increases the antinociceptive effects of morphine in monoarthritic rats (48). in addition, metamizole administration before surgery has been reported to reduce the postoperative consumption of morphine in humans (98).…”

Isobolographic Analyses of the Gabapentin-Metamizol Combination after Local Peripheral, Intrathecal and Oral Administration in the Rat

“…On the other hand, metamizol has shown synergism in combination with morphine [39,45] , tramadol [46] and B vitamins [47] . Co-administration of gabapentin and metamizol produced a significant synergistic interaction at the different levels assessed.…”