Morphine onset of action is approximately how long?

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Multiple Choice

Morphine onset of action is approximately how long?

Oral morphine has a slower onset because it must be absorbed through the gastrointestinal tract and undergo first-pass metabolism in the liver. This delays the time to analgesic effect, so the noticeable relief typically appears around 60 minutes after administration, with peak effect near that timeframe in children and adults. That’s why about an hour is the best answer for oral morphine. In contrast, drugs given by intravenous route act within minutes, and intramuscular administration is faster than oral but still not as prompt as IV. A two-hour onset is longer than expected for the common oral use, and 15–20 minutes would not apply to oral morphine.

Oral morphine has a slower onset because it must be absorbed through the gastrointestinal tract and undergo first-pass metabolism in the liver. This delays the time to analgesic effect, so the noticeable relief typically appears around 60 minutes after administration, with peak effect near that timeframe in children and adults. That’s why about an hour is the best answer for oral morphine. In contrast, drugs given by intravenous route act within minutes, and intramuscular administration is faster than oral but still not as prompt as IV. A two-hour onset is longer than expected for the common oral use, and 15–20 minutes would not apply to oral morphine.

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