Your vet or pharmacist should have been able to clear up your confusion.
Biaxin comes in 4 different sizes:
1) 50mls of 125mg/5ml (ie 25mg/ml),
2) 100mls of 125mg/5ml (ie 25mg/ml),
3) 50mls of 250mg/5ml (ie 50mg/ml), and
4) 100mls of 250mg/5mls (ie 50mg/ml).
Thus the "Half Strength" is the 125mg/5mls (ie 25mg/ml).  The dose is
25mg/kg, so it would be 1ml/kg.  It is used three times a day for at
least 14 days.  Thus a 1 kg ferret would get 3mls per day for 14 days
which is 52mls or a whole bottle of the 50ml size, or half of the bottle
of the 100ml size.
 
Yes, it is a good idea to use amoxidrops or clavamox drops with the
Biaxin.  Liquid carafate (1ml or 100mg) about 10 minutes before feeding,
4+ times a day is also still recommended.  Pepcid, Zantac, Prilosec, or
Tagamet can be used on a short times basis if the ferret is not eating or
showing signs of pain right after eating.  A bland diet such as Hill's
a/d or Gerber's baby food (turkey or chicken) is also recommended.
 
You can read more about ulcers in Ferrets magazine, March/April 2004
p 18-23.
 
Hope that helps,
Jerry Murray, DVM
Dallas, Texas.
[Posted in FML issue 4557]