If you're talking about a gradual buildup, it's just tolerance. But if you're talking about the first time using, remember that everybody's physiology is different: weight, natural chemical balance, and the # of different receptors on the brain vary from person to person, and all effect the body's reaction to drugs. A small few people are even immune to the effect of certain drugs.
Effect
Tolerance
A psychological dependence is a person's belief that he or she needs a drug to feel good or to function normally. A physical dependence is a condition where a person has a physical or chemical dependence on the drug.
When a person needs a drug to feel normal, he or she has an addiction.
Physical dependence occurs when a person develops a tolerance to the effects of a drug and needs larger and larger doses to achieve intoxication or another desired effect.
Drug effect is the behavior of person after drugs. People are generally not in their senses.
A placebo.
addiction
Addiction
Addiction.
Yes, that would be considered practicing medicine without a license. What would you do if that person had a severe allergic reaction or some other adverse effect from the drug? What if that person was on another drug that was similar and the effect was doubled, or had a bad reaction from the combination. This needs to be handled by a medical doctor.
tolarance