The correct answer is (d) Antibiotics
The explanation: For polar drugs for e.g. antibiotics which distribute in excess body space of obese patients to an extent less than that in lean tissues. Thus, the dose should be lesser on per kg total body weight basis but more than that on IBW basis. Drugs such as caffeine, theophylline, lidocaine and lorazepam get distributed in same extent in both lean and adipose tissues. For drugs such as digoxin which do not distribute in the excess body space, the volume of distribution does not change and hence dose for administration to a patient should be calculated on the basis of ideal body weight.