Combinations - Wellbutrin / Bupropion and drugs

[Princess]

Wellbutrin has interactions with other drugs, but is that only if the Wellbutrin is in effect at the time, or is it anytime when someone is taking it? If someone is taking Wellbutrin SR 75 that lasts eight hours, when it wears off, would someone be able to use other substances without any interactions, or is the Wellbutrin still in effect when it's worn off? Also, how long would someone have to be off Wellbutrin before prescription amphetamines or stimulants would have the old affect? Would you have to be off Wellbutrin SR for awhile before amphetmaines/stimulants have their old euphoric effect? If Wellbutrin has worn off, would it still have interactions with other substances, or is it still going through your brain? Any SWIYs know about this?