BackgroundAlpelisib was approved for treatment of breast cancer. We assessed the safety signals associated with alpelisib by data mining the FDA pharmacovigilance database. MethodsData from the second quarter of 2019 to the fourth quarter of 2022 had been retrieved from the FAERS database. Disproportionality analysis by reporting odds ratio were used to evaluate the potential association between adverse events (AEs) and alpelisib. ResultsA total of 5,980,090 reports were extracted, 18,149 of them were chosen with alpelisib as the suspected drug. After combining the same PRIMARYID, 5647 patients remained. We observed 10 system organ classes (SOCs) with a reported number >50 and associated with alpelisib as gastrointestinal disorders, general disorders and administration site conditions, metabolism and nutrition disorders, skin and subcutaneous tissue disorders, investigations and neoplasms benign, malignant and unspecified (incl cysts and polyps), immune system disorders, nervous system disorders, psychiatric disorders, eye disorders. The median time to AEs in these patients was 13 days, with an IQR (Interquartile Range) of 7–70 days. 61.12% AEs happened within the initial month of alpelisib usage. ConclusionOur study provided a more in-depth and extensive understanding of AEs that may be associated with alpelisib, which will help to reduce the risk of AEs in the clinical treatment of alpelisib. AEs with novel preferred term (PTs) were constipation, dysphagia, diabetic ketoacidosis, feeding disorder, urticaria, eye disorders and vision blurred. 61.12% of cases developed AEs within 30 days after taking alpelisib.