In short-to-moderate intake durations (months to a year) and in moderate doses, rhodiola is safe, with little to no side effects. Although reports of adverse effects are rare, dizziness, dry mouth, and headache were noted in a small number of participants in some trials.[1][2] Rhodiola has been shown to interact with liver enzymes in vitro, indicating a possibility for drug interactions. It increased the concentration and decreased clearance of a particular antihypertensive drug in rabbits,[3] confirming interaction with at least one class of drugs in vivo.