Providing treatment side effect information to patients increases the risk of harm due to the nocebo effect. Nocebo education, in which patients learn about nocebo effects, is a novel strategy that can be used across a variety of situations and individuals to decrease unpleasant treatment side effects. It is currently unclear which psychological changes are induced by nocebo education, which is information required to maximize this intervention. Two pre-registered studies investigated the effects of nocebo education on side effect expectations, side effect control beliefs, feelings toward treatments, intentions to avoid or seek side effect information, and perceptions of treatment efficacy. In Study 1 (N = 220), adult participants either watched or did not watch a nocebo education intervention video prior to reading vignettes about receiving a surgical treatment for pain and a medication for pain. Study 2 (N = 252) was similar to Study 1, with the inclusion of a health behavior video control group and participants only reading about a medication treatment for pain. In both experiments, nocebo education reduced global side effect expectations and increased side effect self-efficacy beliefs. Nocebo education also increased intentions to avoid side effect information and decreased intentions to seek more side effect information. Evidence was inconclusive on whether nocebo education changes affective associations with the treatments. The findings demonstrate that nocebo education has a multi-faceted influence with the potential to change patient behavior. The results can be used to improve the management of adverse treatment side effects.