New technologies regularly bring about profound changes in our daily lives. Romantic relationships are no exception to these transformations. Some philosophers expect the emergence in the near future of love drugs: a theoretically achievable biotechnological intervention that could be designed to strengthen and maintain love in romantic relationships. We investigated laypeople’s resistance to the use of such technologies and its sources. Across two studies (Study 1, French and Peruvian university students, N after exclusion = 186; Study 2, Amazon Mechanical Turk sample, N after exclusion = 693, pre-registered), we found that the use of love drugs designed to strengthen and maintain love in romantic relationships are considered as more morally problematic than psychological therapy with the same aim. In Study 2, we show that this last effect is partially due to the fact that the love resulting from the use of love drugs is perceived as less authentic, intense, and durable. We discuss the specific role of authenticity in the relative moral disapproval of love drugs.