This is an interesting question. I'm allergic to codeine, so it would be good for me to know how long it stays in the body as well.
A definitive answer will depend on the amount of the dosage taken, but, according to Rutgers University Health Services, generally codeine stays in body tissue 1-2 days.
Codeine is a narcotic pain reliever and is often used in cough medications to ease coughing. It is a protected substance and can be obtained only through a doctor's prescription. It can be habit forming, so whether a person is allergic to it or not, it should be taken with care.
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