Fentanyl-trazodone-paracetamol triple drug combination: Multimodal analgesia in a mouse model of visceral pain

►Fentanyl-trazodone-paracetamol display a synergistic interaction on antinociception. ► The combined treatment don't affect exploratory activity and motor coordination. ► Multimodal analgesia by the triple combination leads to a higher benefit/risk profile. ► Naloxone abrogates the enhanced antinociceptive effects of the three-drug treatment. ► The opioid endogenous system may be involved in the synergistic drug-drug interaction.