Tramadol (Post-Operative Pain)

How it works

It is a weak mu-opioid receptor agonist whose active metabolite provides most of the opioid effect, and it additionally inhibits noradrenaline and serotonin reuptake, contributing to analgesia.

Prescribing in practice

• It can cause respiratory depression and lowers the seizure threshold, so avoid in uncontrolled epilepsy and combine cautiously with other CNS depressants, while its serotonergic action risks serotonin syndrome with SSRIs, SNRIs, MAOIs and other serotonergic drugs.
• Analgesic response varies with CYP2D6 metaboliser status, giving reduced effect in poor metabolisers and exaggerated opioid effects in ultra-rapid metabolisers.
• Reduce exposure and lengthen the interval in renal or hepatic impairment and in the elderly, and review the continued need post-operatively to limit dependence.

Monitoring

Monitor pain control, sedation, respiratory rate and bowel function, watching for signs of serotonin toxicity when serotonergic drugs are co-prescribed.

Counselling the patient

• It can make you drowsy and dizzy, so do not drive until you know how it affects you and avoid alcohol.
• Report agitation, shivering, twitching, a fast heartbeat, or any difficulty breathing.
• Use it only as prescribed and do not stop abruptly after prolonged use.

Evidence & guidelines

Tramadol is widely used for post-operative analgesia with efficacy and cautions documented in the SPC and UK pain-management guidance.