This is an old thread, but since somebody has dragged it up again, I'll add that I just read in a pharaceutical textbook that lactose should be avoided as an excipient for tabletting amines, because amines will react with sugar. The exact reaction is not mentioned, maybe somebody knows what it is. Anyway, I would like to amend my post from last year on how to make tablets and recommend using just micro-crystalline cellulose and 3% magnesium stearate as only excipients when tabletting. (I don't think stearic acid is necessary if enough mag stearate is used.) A glidant might be also added, if using a machine and powder is sticking in hopper. But 72% MCC and 3% mag stearate plus 25% active ingredient should do the trick--NOTE I can't absolutely guarantee this, because SWIA don't make pills anymore, but I've a strong hunch it will work.
Anyway, heads up on lactose and amines.
Regards