In comparison to other substituted amphetamines, 4-FA is particularly free of side effects such as nausea, high blood pressure, anxiety and an uncomfortable offset. In low doses, it is considered to be an extremely functional and effective nootropic for performing tasks or general productivity of any sort. At higher dosages, however, it becomes dysfunctional and recreational due to the intensity of its euphoria and stimulation.
The first 4 – 5 hours of 4-FA present distinct entactogenia that feels somewhat similar to MDMA although not quite as powerful. After this first phase of the experience the sensation then shifts towards something which feels like extremely clean amphetamine.