Dear editor,

Flower Remedies, also known as "Bach Flowers Remedies" in honor of their creator -the English homeopath Edward Bach (1886-1936)- claim that water can acquire healing properties when certain wild flowers are submerged in it. Despite the lack of biological plausibility, this type of therapy is taught and used by health professionals, such as doctors and psychologists, to treat various mental conditions including anxiety, stress or depression.

The systematic review by Ernst ¹ reported six randomized clinical trials comparing Bach flowers with placebo. He found that their efficacy to reduce anxiety or stress levels is similar to placebo; however, no randomized clinical trials were found that evaluated their efficacy for the management of depression. ¹

In some countries, Bach flowers are even used by formal health systems, as in the case of Peru's Social Security system. ² This could have serious consequences, such as the impoverishment of patients, the inadequate use of resources allocated to health (which could be rather allocated to therapies that have already been tested), and the potential harm to patients (including complications such as suicide) because of not providing the best available treatment. ³

Accordingly, how can we understand the fact that this therapy is used without evidence that supports its effectiveness? We propose three possible explanations for this paradox:

The first is the lack of knowledge of health professionals about the results of clinical trials. In order to prevent this, it is necessary to strengthen the acquisition of critical thinking skills, at least in university education and, as far as possible, in school education.

The second possible explanation is the "post hoc ergo propter hoc" fallacy. In other words, if a professional uses this therapy in a patient and then sees an improvement, they may believe that this is the result of the therapy used. However, they may ignore, on the one hand, that it may also be related to other factors such as social desirability bias, placebo effect or regression toward the mean and, on the other, that patients who did not improve were less likely to return to consultation. For this reason, randomized clinical trials are required to strengthen the cause-effect relationship. ⁴

Third, some professionals may argue that, while this therapy may not be better than placebo, the use of placebo as a complementary treatment (along with effective therapies) can bring great benefits to the patient. However, if this were the case, the academic community should be aware that what it is bein used a placebo, and that it must be compared with other placebos in terms of costs and side effects before choosing any of them. Likewise, if these placebos are presented as effective, patients could be deceived and the bioethical principle of autonomy ⁵ violated, possibly without a valid reason since recent studies suggest that it is not always necessary to "deceive" patients to achieve an adequate placebo effect. ⁶

Therefore, we believe it is important to open the discussion on the use of unproven treatments for the management of mental conditions and to ensure that the institutions responsible for the health of the population guarantee the best available treatments for the patients. In addition, they should strive to inform the patients about the effectiveness and potential dangers of unproven treatments.