It may not be possible to provide you the desired answer as your query is not very coherent. If a person has not taken a dose of amphetamine or any related drug such as methamphetamine, then of course their drug test will not show a positive result. There is no reason why a drug should be detected if it has not actually been consumed. On the other hand, if you are referring to the time when the dose has been taken - whether, for example, avoiding a dose of amphetamine for 24 hours before a test will still give a positive result - then the answer is more complex, and depends on several factors. The body takes time to metabolize any drug, and the drug may be excreted after many days following consumption. At the same time, the drug will not begin to be excreted till at least a few hours after consumption, which is why urine tests cannot detect amphetamine consumption immediately (if of course the person has previously been “clean”). In the blood, amphetamine can be detected up to 12 hours later, while in the urine it can be detected even 3 days later.
You should also note that methamphetamine is converted to amphetamine in the body, and a drug test will detect either drug. Therefore, the fact that you have not taken a dose of amphetamine recently means nothing if you have instead taken methamphetamine. The drug test will still give a positive result, which will indicate that you have taken either methamphetamine or amphetamine. If you have no valid explanation for these results, such as a prescription or a medical condition that requires you to take the drug, you can certainly expect to be in trouble.
However, another aspect of this should also be noted. Several unrelated drugs may eventually, as a result of metabolic processes, be partially converted to amphetamine in the human body. For example, prenylamine, a drug used to treat angina pectoris, is known to lead to false positives in drug tests. Selegiline, which is used to treat Parkinson’s disease and senile dementia, can also result in a false positive on a drug test. Benzphetamine, a drug that is closely related to amphetamine but does not have the same potential for abuse, can also be detected as amphetamine in a drug test, leading to what is essentially a false positive. Of course, with all these drugs, the potential for false positives is well recognized, and if you have a prescription, this should be adequate explanation for your test results.
Submitted by M T on January 27, 2010 at 04:03