In my experience, which at 20+ years is no trivial thing, that question doesn�t have a set, easily stated answer.
It�s not something like acid, where you can emphatically, empirically state an answer in terms of mics. Or any type of pill where you can give an answer in terms of number of pills and such.
Of course I�m sure to get a lot of rebuttals to this argument.
So I�ll try to be a little more clear, but � I�ll tell you now � I�m finding this one very hard to put into words, which will amuse certain people to no end

.
When you say �safe dose�, I assume that you mean not just a level which won�t kill you, but one that won�t have you thinking you took too much: a level that will give a good ride.
And I just can�t give you an empirical answer.
Again using acid as an example, I would say that between 200 and 599 mics would be a good trip [when I took acid it was; I don�t know about today: From the last two experiences I had with it back in 96, I would say they must consider 50 to 100 mics a good trip]
It is more like pot, where you buy, say, an 1/8 bag, which you smoke out of. You can�t, though, give any particular dose used when you smoke.
Meth is like that. You buy, say � gram bag, from which you will use to make lines [if snorting], foils � or pipes [if you are smoking], and so on. You can�t really state how much is in any single line or foil or such.
So, given all of that, I can tell you that [even with very high quality meth] you could probably do that whole � gram bag yourself and be ok.
That�s because you aren�t very likely to do it all at once [unless you are shooting it. In that case, there is nothing I can do to help you since you would either be suicidal or just plane stupid. Not stupid for shooting
per se � though I do think shooting anything anytime isn�t too bright, but that�s just me � No, I mean if you choose to shoot
your first time ,
that would make you stupid, in my book.
Just do a line [or foil, or pipe, etc.] at a time, give some time before you do the next. You will know when you�ve had enough.
I imagine that the same would apply to cat, though with no direct - or indirect � experience I can�t say for sure.
I hope this helps.