A prescription drug called tramadol is used to relieve moderate to severe pain. It is frequently provided when harsher opioids are not thought to be essential yet non-opioid painkillers are insufficiently effective. Like many opioid painkillers, tramadol acts by attaching itself to opioid receptors in the brain. Its analgesic effects may also be attributed to the inhibition of certain neurotransmitters" reuptake, specifically serotonin and norepinephrine.