The ramp effect is a phenomenon involved in drug addiction whereby an addict develops a resistance to a substance, and thus requires increasingly large quantities of that substance to achieve the same effect. This can lead the addict to rapidly increase

Exponential growth

Exponential growth occurs when the growth rate of a mathematical function is proportional to the function's current value...

 their dosages, which can lead to a variety of health maladies.

After the ramp effect has begun, it may be very difficult to deprive an addict of their substance, or even to reduce the dosage. Much of drug rehabilitation

Drug rehabilitation

Drug rehabilitation is a term for the processes of medical or psychotherapeutic treatment, for dependency on psychoactive substances such as alcohol, prescription drugs, and so-called street drugs such as cocaine, heroin or amphetamines...

consists of resisting and reversing the ramping effect.