Nosek K, et al. – This study was designed to compare analgesia and adverse effects of oral morphine and oxycodone and transdermal fentanyl and buprenorphine administration in cancer patients with pain. Investigations suggested that all opioids were effective and well–tolerated. Morphine was the most effective in the improvement in some of the Brief Pain Inventory–Short Form items regarding the negative impact of pain on patients’ daily activities. Moreover, the prophylaxis of constipation was effective.