Change from (total daily dose in mg) Change to (total daily dose in mg)
Oral codeine Oral dihydro- codeine Oral pethidine Oral morphine Oral dextro- moramide Morphine infusion Diamorphine infusion Oral hydro- morphone Sublingual buprenorphine
                  Oral codeine
                  Oral dihydrocodeine
                  Oral pethidine
Divide by 12.5 Divide by 10 Divide by 10   Multiply by 2 Multiply by 3 Multiply by 4 Multiply by 7.5 Multiply by 50 Oral morphine
Divide by 25 Divide by 20 Divide by 20 Divide by 2   Multiply by 1.5 Multiply by 1.5 Multiply by 4 Multiply by 25 Oral dextromoramide
Divide by 40 Divide by 30 Divide by 30 Divide by 3 Divide by 1.5   Multiply by 1 Multiply by 2.5 Multiply by 20 Morphine infusion
Divide by 40 Divide by 30 Divide by 30 Divide by 3 Divide by 1.5 Divide by 1   Multiply by 2.5 Multiply by 20 Diamorphine infusion
Divide by 100 Divide by 75 Divide by 75 Divide by 7.5 Divide by 4 Divide by 2.5 Divide by 2.5   Multiply by 7 Oral hydromorphone
      Divide by 50 Divide by 25 Divide by 20 Divide by 20 Divide by 7   Sublingual buprenorphine

Intended as a guide only - titrate individually according to pain, response and side effects.

Dose conversion from oral morphine to fentanyl transdermal patch

4-hourly morphine dose 24-hourly morphine dose Fentanyl patch size
5-20mg Up to 135mg 25mcg/hr
15-35mg 135-224mg 50 mcg/hr
40-50mg 225-314mg 75mcg/hr
55-65mg 315-404mg 100mcg/hr
70-80mg 405-494mg 125mcg/hr
85-95mg 495-584mg 150mcg/hr
100-110mg 585-674mg 175mcg/hr
115-125mg 675-764mg 200mcg/hr
130-140mg 765-854mg 225mcg/hr
145-155mg 855-944mg 250mcg/hr
160-170mg 945-1034mg 275mcg/hr
175-185mg 1035-1124mg 300mcg/hr