Tramadol Infusion Dilution
Tramadol for intravenous infusion should be diluted to 100 mg in 100 mL of normal saline (0.9% NaCl) or electrolyte solution, administered over 30 minutes as a slow infusion. 1, 2
Standard Dilution Protocol
- Dilute tramadol 100 mg in 100 mL of normal saline or electrolyte solution for intravenous administration 1
- Administer as a slow infusion over 30 minutes to minimize adverse effects 1
- Alternative dilution: 400 mg tramadol in 500 mL electrolyte solution for continuous infusion, which can be given as a loading dose of 125 mL over 10 minutes (equivalent to 100 mg tramadol), followed by maintenance infusion at 12.5-25 mL/h (10-20 mg tramadol/h) 2
Dosing Considerations
- Maximum daily dose is 400 mg for immediate-release formulations (100 mg every 4-6 hours) 3, 4
- Starting dose should be 50-100 mg every 4-6 hours as needed 4
- Tramadol is approximately one-tenth as potent as morphine, requiring higher doses for equivalent analgesia 3, 4
Critical Safety Warnings
- Reduce doses in elderly patients (≥75 years) and those with hepatic or renal dysfunction to minimize seizure risk 3
- Avoid or use with extreme caution in patients taking serotonergic medications (TCAs, SSRIs, MAOIs) due to risk of serotonin syndrome 3, 4
- Slow infusion is essential - rapid administration increases risk of dose-dependent adverse effects, particularly nausea, dizziness, and vomiting 5, 1
Common Pitfalls
- Avoid rapid bolus administration: The most common error is administering tramadol too quickly, which significantly increases nausea and other adverse effects 5
- Onset of action is delayed: Tramadol requires 1-2 hours to reach peak effect, so inadequate early pain control should not prompt immediate dose escalation 5, 6
- Limited efficacy for severe pain: Tramadol is less effective than morphine for severe acute pain and should be reserved for moderate to moderately severe pain 3, 6, 7