Table 3.

Causes of drug-related problems

C, Cause	Sum
C1 Drug selection (total)	118
C1.6 Too many drugs for indication	33
C1.7 Not cost-effective choice	29
C1.3 Inappropriate combination	27
C1.1 Inappropriate drug	23
C1.2 No indication for drug	5
C1.4 Inappropriate duplication	1
C2 Drug form (total)	2
C2.1 Inappropriate drug form	2
C3 Dose selection (total)	43
C3.5 No therapeutic drug monitoring	14
C3.1 Drug dose too low	13
C3.2 Drug dose too high	11
C3.6 Pharmacokinetic problem	4
C3.7 Deterioration/improvement of disease	1
C4 Treatment duration	14
C4.2 Treatment duration too long	14
C5 Drug use process	7
C5.1 Patient gets/takes drug at the wrong times	5
C5.2 Drug under-used/under-administered	1
C5.6 Drug abused (unregulated overuse)	1