Is it true that a powdered capsule of a drug can be broken down into a liquid with distilled water?

that would sort of depend on if it is soluable in water, the substance that is. if you are talkin about phentermine- yes it is very soluable in water.

Aren't there different brand names of phentermines like adipex and fastins? I believe phentermines are anorexiants which also means that they would be phenethylamines, similar to amphetemines, so they are really weight loss medication.

yes phenethylamines,- not psychoactive(psychadelicaly i.e. 2c-t-7 at small enough doses). fastin and adipex p are the same thing: phentermine hcl just diff marketing names. ionamin is a little different: phentermine resin(ewwy) sa(no idea what the sa is for) uhh this shit causes mad heart probs but its speedy and i know a few dumb people that use it when they cant get glass so whatev. short term use only- thats why its a script now and not OTC anymore, dont think it had to do with the fact you can speed on it, since you can on all kinds of legal things that dont cause as many heart and physical probs(and arent used for medical treatment) bzp, tmfpp, ephedra, ephedrine, pseudoephedrine...