Duloxetine
Duloxetine is a serotonin and noradrenaline reuptake inhibitor. By blocking the reuptake of both transmitters it raises their levels in the brain and in the descending pain pathways of the spinal cord, which is why it acts on mood and on nerve pain alike. It is used for depression, anxiety disorders and neuropathic pain.
It can be taken with or without food, and one intake a day is the usual pattern. Combining it with tramadol raises serotonin levels from two directions at once and increases the risk of serotonin toxicity, so that pairing needs medical supervision. Liver enzymes ALT and AST are worth watching because the drug is metabolised in the liver, and blood sodium can drift downward, particularly in older people; the drug can also lower blood pressure, so standing up slowly is sensible early on. It should never be stopped abruptly, as sudden withdrawal brings dizziness, electric-shock sensations and mood swings.
See a doctor for yellowing of the skin or eyes, dark urine or persistent upper-abdominal pain; for confusion, headache or marked weakness that may signal low sodium; and for agitation, fever, shivering or muscle twitching, especially alongside tramadol.
Reference information, not medical advice. Discuss any change with your doctor.