Value of the data •The PsyTAR dataset can be used as a benchmark to train and evaluate the performance of lexicon-based systems and machine learning algorithms to identify adverse drug events (ADEs) and measure drug effectiveness from online healthcare forums, particularly for psychiatric medications. •The PsyTAR dataset can be used to train machine learning systems (e.g. neural network) for normalizing medical concepts in online healthcare communities by extracting the semantic links among the layperson expressions of medical terms and medical standard vocabularies. •The PsyTAR dataset can be used to evaluate the association between different types of ADEs and patient satisfaction (attitude) toward psychiatric medications. •The PsyTAR dataset may also be used to facilitate the seamless exchange of information between patients' expressions of ADEs in personal health records (PHR) and electronic health records (EHRs) [1].