ABSTRACT
Objective: To gather scientific knowledge about the use of drugs that cause interference in the results of laboratory tests. This is an integrative review of the literature that used Lilacs, SciELO and Medline as databases and to search for articles; the keywords in Portuguese and English were selected using Bireme's (DeCS) tests: tests Laboratory interactions, drug interactions and interferences. Research published in English, Portuguese or Spanish was published in the form of articles, reviews, dissertations and theses published between 2009 and 2016. Interference caused by medication is a major problem because the patient may be in use of several prescribed drugs, and mainly by self-medication. Among the most commonly used medications, paracetamol causes an increase in alkaline phosphatase and bilirubin, as well as some corticosteroids, such as hydrocortisone that elevates chlorine through salt and water retention. In hematological examinations the reduction of erythrocytes can be provoked by the use of acyclovir, amitripilina, captopril, cimetidina or levodopa. It emphasizes the importance of an effective clinical evaluation of the patient, so that the use of medicines is seen and thus, guarantee quality in the results of the laboratory tests.