Cheetah House is a non-profit organization that provides information and resources about meditation-related difficulties to meditators-in-distress and providers or teachers of meditation-based modalities https://www.cheetahhouse.org/

A site dedicated to raising awareness of adverse effects in meditation, offering guidelines on recognizing problems, how to seek help, and how teachers/retreat leaders can provide appropriate first aid and give support to the students affected in this way https://meditatinginsafety.org.uk/

David Treleaven give tips and advice for making mindfulness safe and effective for
people who’ve experienced trauma https://davidtreleaven.com/

Official curricula and implementation guidelines, informed consent, screening instruments from the UMASS, Oxford and Bangor mindfulness centers, as well as a folder of research and other resources updated monthly to stay current on new developments https://www.brown.edu/research/labs/britton/resources/meditation-safety-toolbox

Lost in Oblivion – An Exploration of Adverse Meditation Experiences: A meditation teachers description and explanation of a number of adverse experiences and some suggestions on how to work with them http://themindfulnesscircle.com/blog/lost-oblivion-exploration-adverse-meditation-experiences/