options linesize=80 pagesize = 60;

data drugs;
input a c m count @@;
cards;
 1 1 1 911   1 1 2 538   1 2 1 44   1 2 2 456
2 1 1   3   2 1 2 43   2 2 1 2   2 2 2 279
;
proc genmod; class a c m;
   model  count = a c m  / dist=poi link=log obstats;
run;
proc genmod; class a c m;
   model  count = a c m  c*m / dist=poi link=log obstats;
run;
proc genmod; class a c m;
   model  count = a c m a*m   / dist=poi link=log obstats;
run;

proc genmod; class a c m;
   model  count = a c m a*c / dist=poi link=log obstats;
run;

proc genmod; class a c m;
   model  count = a c m a*c  a*m / dist=poi link=log obstats;
run;

proc genmod; class a c m;
   model  count = a c m a*c  c*m / dist=poi link=log obstats;
run;

proc genmod; class a c m;
   model  count = a c m a*m  c*m / dist=poi link=log obstats;
run;

proc genmod; class a c m;
   model  count = a c m a*c a*m  c*m / dist=poi link=log obstats;
run;

proc genmod; class a c m;
   model  count = a c m a*c a*m  c*m a*c*m/ dist=poi link=log obstats;
run;