Can patients with Alzheimer's disease participate in clinical research? Theoretically, two radically opposite views can be hypothesized regarding this problem. The first, rather “conservative”, could, in principle, argue that due to pervasive cognitive deficits, patients with AD are vulnerable and not able to give informed consent with a degree of responsibility similar to that of healthy individuals. When a surrogate's decision is required for research participation, this decision can never be equivalent to the patient's actual decision, since no one can know exactly what the patient wants. This generates important questions regarding the participation of these patients in research especially in light of the ethical principle of autonomy. There are numerous cases where this position is relevant: research involving risks to the patient's health, minimal benefits compared to the risks, or the use of placebos. The second view argues for the merits of research: AD research cannot be conducted without AD patients at all stages of their disease. This is an indubitable fact, because otherwise how can one follow the development of the disease (especially the characteristic biological changes)? Invoking the argument of scientific progress and the possibility of finding a cure, the participation of Alzheimer's disease patients in research is no longer a matter of possibility but of absolute necessity. In this article I will argue that, although the concerns of the first opinion are partially justified, they need not diminish the importance of Alzheimer's patients' participation in research. In the first section of the article I will present some studies that support each of the opinions, then in the second part... halfway through the article... there is little information about the study's possible benefits or side effects. The side effects were significant (gastrointestinal disorders, headache and increased alanine aminotransferase), while the benefits were minimal. This situation highlights the need for a balanced approach when dealing with clinical drug trials. In conclusion, AD patients can participate in research as long as their decision-making capacity is thoroughly examined. Otherwise, an attorney can decide because he or she usually acts in the best interests of the patient. To be considered ethical, the research project involving AD patients must follow the TCPS guidelines and be approved by a research ethics committee. Furthermore, autonomy, clinical balance and careful evaluation of benefits versus risks should be among the main ethical concerns of the study.