Clinical Research Directory

Inclusion Criteria: * Male and female patients receiving a WHO step III opioid (i.e. morphine, oxycodone, methadone, fentanyl, hydromorphone, or buprenorphine) in combination with paracetamol (minimum dose 1.5 g/day) * Age ≥ 18 at screening * Ability to understand the study procedures and to provide written informed consent * Stable analgesia before randomisation, defined as no required changes in the analgesic treatment during the previous 7 days Exclusion Criteria: * Participation in another interventional trial within 30 days prior to randomisation, with the exception of cancer treatment trials * Changes of the dosage or start of other (co-)analgesics (e.g. tricyclic antidepressants, neuroleptics, nonsteroidal anti-inflammatory drugs (NSAIDs), dipyrone), within the last 7 days preceding randomisation * Surgery within the 14 days preceding randomisation or surgery planned within the duration of the study * Any circumstances, comorbidities or conditions, which, in the opinion of the investigator, may affect full participation in the study or compliance with the study protocol