Hello trish13,
It seems that oxycontin should not be detected in a urine test 3 days
after taking the last dose. Some people may well be negative after a
shorter period.
I found the answer to your question on the "Ask the Medical Experts"
section of the web site of CME Inc (Continuing Medical Education Inc).
The question and answer are at
http://www.medinfosource.com/expert/exp3110899d.html
The question is about someone taking Oxycontin 40mg for pain following
a car accident, who is about to start a new job and is required to
have a drug screen. The answer includes the following statement: "The
half-life of oxycontin (the time it takes 1/2 of the medication to
leave the body) is about 5 hours. So after 2 or 3 days, it should be
out of his system. It is important to recognize, however, that
everyone is different, so that it may require a bit more time (or less
time) in your husband."
Another source that confirms these figures is the article "Oxycodone:
Laboratory Procedures for Identifying Overdose and Abuse" by BY ROBERT
H.WILLIAMS which appeared in CLINICAL LABORATORY NEWS MARCH 2003 and
can be accessed as a pdf file here:
http://www.aacc.org/cln/series/oxycodone.pdf You need Acrobat Reader
to be able to view pdf files, and this is available at
http://www.adobe.com/products/acrobat/readstep2.html
Williams writes about oxycodone, which is the generic name for the
drug. The oxycodone product sold as Oxycontin is a controlled release
formulation. "The elimination half-life for immediate-release
oxycodone is 3.2 hours, and for the controlled-release form, it is 4.5
hours." With respect to the urine tests that are performed in drug
screening, he says "The detection window in urine can vary from one to
three days, depending on dose and acute versus chronic use or
tolerance."
The factors that will affect the timing include:
The size of the dose, the frequency with which it is being taken, and
how long it has been taken, as mentioned in the quotation from
Williams above.
The characteristics of the person. These include:
Age and sex, with women and older people taking longer to clear the
drug "Plasma concentrations tend to be 25% higher in females than in
males even after adjustment for body weight. In geriatric patients,
reduced clearance causes an increase in plasma concentration of about
15%."(from Williams)
Health status: Someone with kidney or liver disease will need longer
to eliminate the drug from the body: "Notably, patients with
mild-to-severe renal impairment or mild-to-moderate hepatic
dysfunction show peak plasma levels of oxycodone and noroxycodone (one
of its metabolites) 50% and 20% higher, respectively." (from Williams)
Genetic differences in how people metabolize the drug.
Whether other medication is being used. Williams mentions that
amiodarone, quinidine and polycyclic antidepressants can slow down the
speed at which Oxycintin is eliminated.
Search strategy: oxycontin "half life" |
