relative potencies of morphine via various routes
Last reviewed 09/2021
The relative potency of morphine when given by various routes is given below:
| Route | Potency relative to oral morphine |
| oral morphine | 1 |
| rectal morphine | 1 |
| subcutaneous morphine | 2 |
| intravenous morphine | 3 |
| subcutaneous diamorphine | 3 |
i.e. 3mg oral morphine is equivalent to 1mg of subcutaneous diamorphine
Check summary of product characteristics before prescribing any drugs mentioned.
Reference:
- West Midlands Palliative Care Physicians (2003). Palliative care - guidelines for the use of drugs in symptom control.
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