What is the duration of action for IM morphine?

The duration of action for intramuscular (IM) morphine is typically in the range of 4 to 7 hours. This time frame reflects how long the drug effectively provides analgesia after administration, allowing for a reasonable period of pain relief before additional doses may be required. Morphine is a potent opioid analgesic, and its effects can vary depending on factors such as the individual's metabolism and the specific dose administered.

In a clinical setting, knowing the duration of action is crucial for effective pain management, as it helps healthcare providers plan follow-up doses or alternative pain management strategies. The selection of 4 to 7 hours takes into account the pharmacokinetics of morphine when delivered through intramuscular injection, where onset of action is generally slower compared to intravenous methods but provides a longer window of efficacy than shorter-acting forms.