Addiction: From Tea and Coffee to Drugs of Abuse

Since ancient history mankind has use different types of drugs for diverse purposes, one of these drugs is the caffeine, the caffeine is a central nervous system stimulant wide world used and commercialized.
As for myself, like almost any person, I have tried a drug of abuse, and as you can imagine is the caffeine, I have to say that I take daily a cup of coffee, and for my experience, is good it helps a lot to wake up in the morning.
The caffeine for being a central system stimulant, will reduce fatigue and drowsiness, improving reaction time, wakefulness, and concentration (among others) being this some of the observable effects on a caffeine user.
Caffeine like any drug of abuse has some positive aspects and others negatives ones, for the beneficial aspects it can treat and prevent some diseases, like the apnea of prematurity, in fact caffeine is consider an essential medicine according to the “WHO”, but still has some negative aspects, for example caffeine can produce drug dependence, producing some withdraw symptoms such as sleepiness, headache and irritability.
Caffeine can produce some side effects, since physical effects to psychological ones, some example of physical effects are, increasing blood pressure causing vasoconstriction, increase the basal metabolic rate, and affect gastric acid secretion, on the other hand some psychological effects are insomnia, jitteriness, and other anxiety disorders. Aside this caffeine can be lethal over 10 grams per day for an adult, which are roughly 50–100 ordinary cups of coffee.
Now you may ask if a know some addicted to a drug of abuse, and I think is quite obvious, I think is hard to find someone who doesn’t use any type of drug, but in any case in my family I’m not the only one who use a lot of caffeine, my dad for example takes a lot more cups of coffee than me (like 3-4 cups per day).
I think drugs of abuse are very present is society, and for this many individuals are under the effect of any of them, as for my career (pharmacy), I believe that some of them obviously has some very negative effects to the professionals, like the hard drugs, or alcohol, but “safe” drugs like caffeine, I don’t see the problem of using them (I don’t say this because I use it ok?), of course in normal doses.