You are a bit confused, you have heard some people rave about "biostatic" medications and others talk about "biocidal". Are they the same? Is one better than the other? What you want is to define biocidal and biostatic. Nothing simpler!
Biocidal means to kill life and is frequently listed on a lot of pesticides as well as medications. Just like Homicidal means to be murderous and kill others and suicidal mean to kill yourself. The "cidal" is a dead give-away (pun intended); it means to kill! Cidals are poisons, the kill. An herbicide kills plants; an insecticide kills insects; and a rodenticide kills rodents! "Static" means to stay still and not change, look up "homeostatic" or the word "stasis" in the dictionary.
A biostatic merely slows it down or forces it to stop, but doesn't actually kill. They are generally safer and more difficult to overdose while using. They are mainly found in medications for when you want to slow something down without killing everything else.
Why use one over the other?
Bactericidal drugs kill bacteria and are very important in rapidly getting rid of bacterial infections. Something like Beta-haemolytic Streptococcus can cause complications if in the body too long. It moves to the heart muscle, attaches there and then the antibodies kill it; the heart is weakened. This type of bacteria needs to be killed and killed quickly! But why not use only biocidal medications? Because they can also kill off beneficial bacteria as well as the bad!
Bacteristatic medicines halt or slow down the organism causing the disease. This prevents it from doing excess damage while allowing the body to recognise that it has been invaded. The body will then develop antibodies and remove the problem organisms. This usually gives longer term immunity, you may be safe for life from every getting that type of infection again. The biostatic medication can then be removed and beneficial bacteria start growing again, healthy and, hopefully, happy once more!
Should you be able to choose biocidal over biostatic? Not unless you are a doctor! The doctor will factor in the severity of the disease as well as your current health stasis. Sometimes you need a quick, clean kill as your body may have already been weakened from something else. You may also have a delicate digestive system and the doctor wants to disturb it as little as possible, so just slows things down a bit! Talk with your doctor, but at least now you know the difference between "biocidal" and "biostatic"!