Amphetamine derivatives (i.e. amphetamine itself, pCA, MDMA and fenfluramine) are known since many years but no definitive answer yet exists regarding some important aspects of their pharmacological and/or toxicological effects. This review mainly focus on the current controversies on some open questions, showing the proposed models and discussing the points for or against them. In particular: 1) The monoamine release induced by these drugs is widely assumed to be carrier-mediated. However, recent data indicate that these drugs may also induce a Ca²⁺-dependent, exocytotic-like, neurotransmitter release. Such a mechanism would involve a Ca²⁺-influx through the voltage-operated Ca²⁺-channels. The increase of the intracellular Ca²⁺-concentrations might be relevant for the pharmacological and/or neurotoxic effects of amphetamines. 2) Recent data question the role of presynaptic mechanisms in dFenfluramine-induced anorexia. However, while being true that activation of 5-HT₂C receptors and enhancement of DA release by the d-nor-metabolite may also contribute, it is still not convincingly demonstrated that the released 5-HT has not an important role. 3) The long-lasting decrease of 5-HT and 5-HT transporters induced by some amphetamine derivatives (pCA, MDMA and dFen) is often interpreted as indicating degeneration of 5-HT nerve endings although the available data do not definitively support such conclusion. On the contrary, some of the experimental approaches used indicate differences among amphetamines and suggest that the “neurotoxicity” of some amphetamines may be caused by other mechanisms, such as the regulation of the transcription of specific genes within the 5-HT neurons.