Ketamine is a drug used for the induction and maintenance of general anaesthesia, usually in combination with a sedative. Ketamine as an analgesic has proven to be of some effect in patients with severe pain who have failed to respond to other routinely applied pharmacotherapy. In patients with intractable pain, the use of oral ketamine can be beneficial. From this perspective, oral ketamine may be used with precautions as add-on therapy when other therapeutic options have failed. However, the routine use of ketamine in cancer pain management is still insufficiently studied. After reviewing research which uses ketamine in the management of cancer pain; further RCTs are needed to include all types of cancer to gain more knowledge about the benefits/adverse effects of using ketamine to manage cancer pain. As for recommendation for practice, we recommend the use of Palliative Care Guidelines and to take into consideration the importance of using ketamine and observing any possible side effect that may occur during or after treatment. The impact factor of journal provides quantitative assessment tool for grading, evaluating, sorting and comparing journals of similar kind. 

Citations are important for a journal to get impact factor. Impact factor is a measure reflecting the average number of citations to recent articles published in the journal. The impact of the journal is influenced by impact factor, the journals with high impact factor are considered more important than those with lower ones. To increase the visibility and ease of use of open access scientific and scholarly journals PrimeOA Publications top online publishing journals are indexed in different indexing and archiving services. Indexing provides easy access of the article online.