Morphine has a half-life of 1.5 to 6.5 hours and can be detected in urine for two to three days after ingestion.
Less than 10% of morphine is excreted as morphine. The remainder is excreted as conjugates. In confirmatory testing, a sample preparation step called hydrolysis is often used to break the glucuronide bond to convert the glucuronides back to free morphine.
Positive morphine drug tests can be due to the ingestion of codeine, morphine, or heroin. If the presence of morphine is due to morphine ingestion only, morphine alone will usually be detected in the urine. With high doses of morphine, hydromorphone may also be detected.
Consumption of poppy seeds or an herbal tea containing Papivaris fructus can yield a positive morphine and codeine result on a urine drug test.
