Drug classes	Examples	Coefficient of variation
1	C04A	Peripheral vasodilators (cinnarizine, nimodipine, etc.)	196.99
2	N06D	Anti-dementia drugs (piracetam, levocarnitine, etc.)	179.56
3	C10A B	Fibrates (gemfibrozil, clofibrate, etc.)	156.26
4	H05B A	Calcitonin preparations	135.71
5	N05C	Hypnotics and sedatives (temazepam, phenobarbitone, etc.)	121.21
6	R05C	Expectorants (acetylcysteine, guaifenesin, etc.)	92.05
7	H01A C	Growth hormone (somatropin)	91.41
8	R03D A	Xanthines (theophylline, aminophylline, etc.)	85.01
9	A02B C	Proton pump inhibitors (omeprazole, lansoprazole, etc.)	82.10
10	R03B A	Glucocorticoids, inhalants (beclomethasone, budesonide, etc.)	78.80
11	C10A A	HMG CoA reductase inhibitors (simvastatin, pravastatin, etc.)	73.53
12	N03A	Antiepileptics (phenytoin, carbamazepine, etc.)	72.55
13	S01E	Antiglaucoma preparations and miotics (pilocarpine, timolol, etc.)	71.24
14	M05B	Drugs affecting mineralization (alendronate, etidronate, etc.)	68.59
15	R03A	Adrenergics, inhalants (salbutamol, salmeterol, etc.)	63.16
16	N04	Anti-Parkinson drugs (levodopa, bromocriptine, etc.)	58.21
17	A07E	Intestinal anti-inflammatory agents (sulfasalazine, mesalazine, etc.)	56.43
18	A10A	Insulins and analogues	55.40
19	H03B	Antithyroid preparations (thiamazole, propylthiouracil, etc.)	48.83