Single drugs 1. Tricyclic antidepressants Amitryptyline Doxepine Trimipramine 2. First-generation antihistamines Dexchlorpheniramine Promethazine Alimemazine Hydroxyzine 3. First-generation (low-potency) antipsychotics Chlorpromazine Chlorprotixene Levoprometazine Prochlorperazine 4. Long-acting benzodiazepines Nitrazepam Flunitrazepam 5. Muscle relaxant Carisoprodol 6. Strong analgesics Propoxyphene Pethidine Opioids with spasmolytics 7. Theophylline tablets

Combination of drugs 8. Combination of a beta-blocker with either: Verapamil or Diltiazem 9. Combination of an NSAID and warfarin 10. Combination of an NSAID (or a COX-2 inhibitor) with an ACE inhibitor or an ARB 11. Combination of an NSAID and SSRI 12. Combination of an NSAID and a diuretic 13. Concurrent use of ≥3 psychotropic drugs within classes: Opioid analgesics Hypnotics Tranquillisers Antipsychotics Antidepressants

ACE = angiotensin-converting enzyme. ARB = angiotensin receptor blocker. NSAID = non-steroidal antiinflammatory drug. COX = cyclooxygenase. SSRI = selective serotonin reuptake inhibitor.