"tolerance" - this mainly means that the dopamin rezeptors within the brain get damaged continuously, on of the notorious sideeffects of opium use is known to be inactivity.
This does not mean that the subject aquires the addiction via upping the dose to to the tolerance, the addiction is most likely already there.
Quick search shows that 1-2 weeks of consuming lead to a 100% certain addiction, and 1-2 weeks is a far to short time to reach a level of "tolerance" let alone to reach the known long term effect of damaging the receptors in the brain.
http://de.wikipedia.org/wiki/Abh%C3%A4ng...spotential
http://de.wikipedia.org/wiki/Heroin#Abh.C3.A4ngigkeit
This does not mean that the subject aquires the addiction via upping the dose to to the tolerance, the addiction is most likely already there.
Quick search shows that 1-2 weeks of consuming lead to a 100% certain addiction, and 1-2 weeks is a far to short time to reach a level of "tolerance" let alone to reach the known long term effect of damaging the receptors in the brain.
http://de.wikipedia.org/wiki/Abh%C3%A4ng...spotential
http://de.wikipedia.org/wiki/Heroin#Abh.C3.A4ngigkeit