Fentanyl Patch (Burns Pain)

⚠️ CONTRAINDICATED IN ACUTE AND POST-OPERATIVE PAIN (§4.3, verbatim): 'Acute or post-operative pain because there is no opportunity for dose titration during short-term use, and because serious or life-threatening hypoventilation or persistent post-operative opioid use could result.' TITRATION: 'The dosage may subsequently be titrated upwards or downwards, if required, in increments of either 12 or 25 mcg/h... Dosage titration should normally be performed in 12 mcg/h or 25 mcg/h increments (oral morphine 45/90 mg/day ≈ Durogesic DTrans 12/25 mcg/h). After an increase in dose, it may take up to 6 days for the patient to reach equilibrium on the new dose level. Therefore after a dose increase, patients should wear the higher dose patch through two 72-hour applications before any further increase in dose level is made.' ONSET: 'Initial evaluation of the maximum analgesic effect of Durogesic DTrans cannot be made before the patch is worn for 24 hours... Previous analgesic therapy should therefore be gradually phased out after the initial dose application.' SPC TABLE 2 (opioid rotation or clinically less stable patients, 150:1) — oral 24-hour morphine <90 mg/day → 12 micrograms/hour; 90–134 → 25; 135–224 → 50; 225–314 → 75; 315–404 → 100; 405–494 → 125; 495–584 → 150; 585–674 → 175; 675–764 → 200; 765–854 → 225; 855–944 → 250; 945–1034 → 275; 1035–1124 → 300. Conversion multiplication factors to the equianalgesic 24-hour ORAL MORPHINE dose (§4.2 Table 1) include: morphine oral ×1, parenteral ×3; oxycodone oral ×1.5, parenteral ×3; hydromorphone oral ×4, parenteral ×20; codeine oral ×0.15, parenteral ×0.23; tramadol oral ×0.25, parenteral ×0.3; methadone oral ×1.5, parenteral ×3; parenteral fentanyl ×300; parenteral diamorphine ×6; parenteral pethidine ×0.4; oral tapentadol ×0.4; sublingual buprenorphine ×75, parenteral ×100. 'Tables 1, 2, and 3 should only be used to convert from other opioids to Durogesic DTrans and not from Durogesic DTrans to other therapies to avoid overestimating the new analgesic dose and potentially causing overdose.' ABOVE 100 micrograms/hour: 'More than one Durogesic DTrans patch may be used for doses greater than 100 mcg/h'; 'Some patients may require additional or alternative methods of opioid administration when the Durogesic DTrans dose exceeds 300 mcg/h' — that is a prompt to reconsider the route, NOT a stated maximum, and NO MAXIMUM DOSE is stated in this SPC, so no ceiling is published. IF A PATCH FALLS OFF before 72 hours, apply a patch of the same strength to a different skin site and monitor closely (serum concentrations may rise). If analgesia is insufficient during the first application only, the patch may be replaced after 48 hours with one of the same dose, or the dose increased after 72 hours. STOPPING: replace with other opioids gradually, starting low — 'It may take 20 hours or more for the fentanyl serum concentrations to decrease 50%'; taper to avoid withdrawal. ELDERLY: observe carefully and individualise; in opioid-naïve elderly patients 'only Durogesic DTrans 12 mcg/h dosage should be considered for initial treatment'.

NOT a per-kg regimen — the paediatric dose is derived from the child's existing 24-hour oral morphine dose, so no figure is set for the weight calculator. ELIGIBILITY, verbatim §4.2: 'Durogesic DTrans should be administered to only those opioid-tolerant paediatric patients (ages 2 to 16 years) who are already receiving at least 30 mg oral morphine equivalents per day.' SPC Table 4 (paediatric conversion): oral 24-hour morphine 30–44 mg/day → 12 micrograms/hour; 45–134 mg/day → 25 micrograms/hour; 'Conversion to Durogesic DTrans dosages greater than 25 mcg/h is the same for paediatric patients as it is for adult patients (see Table 2).' 'In two paediatric studies, the required fentanyl transdermal patch dose was calculated conservatively: 30 mg to 44 mg oral morphine per day or its equivalent opioid dose was replaced by one Durogesic DTrans 12 mcg/h patch.' 'Children aged 16 years and above: Follow adult dosage.' 'Durogesic DTrans should not be used in children aged less than 2 years because the safety and efficacy have not been established.' SWITCHING: 'during the first 12 hours after switching to Durogesic DTrans, the patient should be given the previous regular dose of analgesics. In the next 12 hours, these analgesics should be provided based on clinical need.' MONITORING: 'Monitoring of the patient for adverse events, which may include hypoventilation, is recommended for at least 48 hours after initiation of Durogesic DTrans therapy or up-titration of the dose.' The conversion schedule must not be used in reverse (patch → another opioid), 'as overdosing could then occur'. Verify all under-18 dosing against a children's formulary and with the specialist pain or palliative care team before administration.