Provide a formal definition of anhedonia

Mental health and substance use disorders (MH/SUDs) are complex, and for some conditions there may never be a single medication that effectively treats an entire condition (e.g., major depressive disorder, bipolar disorder, or schizophrenia). However, researchers have successfully mapped many specific symptoms onto specific neuronal circuits.[1] For example, researchers have mapped the neuronal circuitry for anhedonia, the reduced ability to experience pleasure. Anhedonia is an important and overlooked aspect of opioid use disorder.[2] Where good supportive data exists, the FDA should give a formal indication for medications to treat specific symptoms such as anhedonia regardless of MH/SUD diagnosis.

FDA-approved indications for medicines to treat specific psychiatric symptoms would encourage on-label prescribing across diagnoses where an individual experiences that specific symptom. Such indications would also encourage medication development because medications to treat a specific symptom that has been mapped onto a specific neuronal circuit would have broader indications than one or more diagnoses.