Tramadol, sold under the brand name Ultram among others, is an opioid pain medication used to treat moderate to moderately severe pain. When taken by mouth in an immediate-release formulation, the onset of pain relief usually begins within an hour. It is also available by injection. It is available in combination with paracetamol (acetaminophen). As is typical of opioids, common side effects include constipation, itchiness, and nausea. Serious side effects may include hallucinations, seizures, increased risk of serotonin syndrome, decreased alertness, and drug addiction. A change in dosage may be recommended in those with kidney or liver problems. It is not recommended in those who are at risk of suicide or in those who are pregnant. While not recommended in women who are breastfeeding, those who take a single dose should not generally stop breastfeeding. Tramadol is converted in the liver to O-desmethyltramadol (desmetramadol), an opioid with a stronger affinity to the μ-opioid receptor. Tramadol is also a serotonin–norepinephrine reuptake inhibitor (SNRI).Tramadol was patented in 1963 and launched under the name "Tramal" in 1977 by the West German pharmaceutical company Grünenthal GmbH. In the mid-1990s, it was approved in the United Kingdom and the United States. It is available as a generic medication and marketed under many brand names worldwide. In 2020, it was the 35th most commonly prescribed medication in the United States, with more than 17 million prescriptions. Medical uses
Tramadol (a schedule IV drug in the US) is used primarily to treat mild to severe pain, both acute and chronic.
In 2011, 21,649 emergency room visits in the United States were related to tramadol. Interactions
Tramadol can interact with other medications with similar mechanisms of action. Tramadol acts as a serotonin-norephinephrine reuptake inhibitor and thus can interact with other serotonergic medications (selective serotonin reuptake inhibitors, serotonin–norepinephrine reuptake inhibitors, tricyclic antidepressants, triptans, cough and cold medications containing dextromethorphan, herbal products containing St. John’s wort, and medications that inhibit the metabolism of serotonin, such as monoamine oxidase inhibitors) and, in combination, may lead to serotonin syndrome. It may also make some  serotonergic antagonist anti-emetic medications (ondansetron) less effective.Tramadol also acts as an opioid agonist and thus can increase the risk for side effects when used with other opioid analgesics (such as morphine, pethidine, tapentadol, oxycodone, and fentanyl).Tramadol is metabolized by CYP2D6 enzymes which contribute to the metabolism of approximately 25% of all medications. Any medications with the ability to inhibit or induce these enzymes may interact with tramadol.Tramadol increases the risk for seizures by lowering the seizure threshold. Using other medications that lower seizure threshold (such as antipsychotic medications or amphetamines), further increases this risk. Pharmacology
Mechanism of action
Tramadol induces analgesic effects through a variety of different targets on the noradrenergic system, serotoninergic system and opioid receptors system. Tramadol exists as a racemic mixture, the positive enantiomer inhibits serotonin reuptake while the negative enantiomer inhibits noradrenaline re-uptake, by binding to and blocking the transporters. Tramadol has also been shown to act as a serotonin releasing agent.