Depending on your bodies metabolic rate, Methylphenidate will probably stay in your system 1-2 days as far as being detected by a urine analysis. For more info check http://health.rutgers.edu/drugs/DrugChart.htm.
Acoording to: http://www.ipassedmydrugtest.com/drug_detection_times.asp Ritalin (Methylphenidate) is 1-2 days.
There are no substances that will increase the excretion of this from the body.
There are certain factors that may influence the amount of time that methadate will stay in your body. However, the average person will have it in the system for a day.
how long does codeine stay in system
Not as long as it will stay in short fine hair, but it will stay for awhile.
72 hours
forever
1day
72 hours
why
Inositol, depending on the dosage, can stay in your body up to a month after you stop taking it. Symptoms can last that long also.
As soon as your body has absorbs it which is not long