Final answer:
The abbreviation PRN stands for Pro Re Nata, meaning 'as needed.' The prescription instructs the administration of Morphine 8mg IM every 4 hours as needed for pain relief.
Step-by-step explanation:
In the context of this prescription, the abbreviation PRN stands for Pro Re Nata, which means "as needed."
So, the prescription is stating that the medication Morphine should be administered at a dosage of 8mg via intramuscular injection every 4 hours as needed for pain relief.
By using the term PRN, the healthcare provider is indicating that the administration of the medication should be based on the patient's pain levels and the effectiveness of the previous dose.
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