ATC Code N02AX02
Formula C16H25NO2
Molar Mass (g·mol−1) 263,38
Physical State solid
Melting Point (°C) 178-181
PKS Value 9,41
CAS Number 27203-92-5
PUB Number 33741
Drugbank ID DB00193
Solubility very soluble in water and methanol, sparingly soluble in acetone


Tramadol is a painkiller from the group of opioid analgesics. It is used to treat moderate to severe pain. Due to its better tolerability compared to other opioids, tramadol is considered a "low risk" opioid. Indications for use include: Post-surgery pain, injury, or chronic pain. Tramadol is often given as a tablet or capsule, but can also be given as a suppository or intravenously. As with all opioids, there is a potential for dependence associated with its use. Tramadol is available only on prescription.



Tramadol achieves its main effect via an agonistic (activating) action at the so-called μ-opioid receptor. Tramadol also binds weakly to the other two known opioid receptors. In doing so, its affinity is 6000 times lower than that of morphine. By binding to these receptors, the perception of pain is dampened. However, tramadol has a second mechanism of action that is partly responsible for pain relief. Tramadol inhibits the reuptake of serotonin and norepinephrine into the presynapse, permanently increasing their concentration in the synaptic cleft. Both neurotransmitters are involved in pain transmission. As a result, pain is further additionally alleviated and mood is improved (antidepressant effect).


Tramadol is rapidly and almost completely absorbed via the gastrointestinal tract. The bioavailability is about 75%. The maximum plasma concentration of tramadol (after oral administration) is normally reached after 1-2 hours. Only 20% of the given dose is bound to plasma proteins. Tramadol is metabolized in the liver into at least 23 different metabolites. The enzyme that catalyzes these reactions is CYP2D6. 90% of the dose is ultimately excreted by the kidneys. the remaining 10% is excreted by the body in the stool. The elimination half-life is 5-6 hours.

Drug interactions

Taking it together with bupropion or MAO inhibitors may cause serious side effects. In addition, concomitant use of centrally depressant substances, benzodiazepines, carbamazepine, anticoagulants and substances that increase serotonin levels (antidepressants, cocaine, ecstasy) should be avoided.


Side effects

Common side effects include:

  • Headache
  • Nausea
  • Constipation
  • Fatigue
  • Sweating
  • Dry mouth

There is a risk of dependence associated with the use of tramadol.

Toxicological data

LD50 (mouse, oral): 350 mg/kg


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The contents shown do not replace the original package insert of the medicinal product, especially with regard to dosage and effect of the individual products. We cannot assume any liability for the correctness of the data, as the data was partly converted automatically. A doctor should always be consulted for diagnoses and other health questions. Further information on this topic can be found here.