As of my last knowledge update in January 2022, it's challenging to predict with certainty whether sound healing will become a mainstream form of medicine in the future. The field of medicine is continually evolving, and there is growing interest in exploring complementary and alternative therapies. However, several factors influence whether sound healing or any alternative approach becomes widely accepted in the medical community:

1. Scientific Evidence: For any healing modality to be widely accepted in mainstream medicine, rigorous scientific research and evidence are crucial. While there is some research on the therapeutic effects of sound, more comprehensive and well-designed studies are needed to establish its efficacy and mechanisms of action.
2. Medical Community Acceptance: The acceptance of a new form of medicine often depends on the endorsement and support of the medical community. This includes healthcare professionals, researchers, and regulatory bodies. For sound healing to be widely embraced, it would need to undergo scrutiny and acceptance by the medical establishment.
3. Integration into Standard Care: The integration of sound healing into standard medical care practices would require collaboration between traditional healthcare providers and practitioners of alternative therapies. Establishing guidelines, protocols, and training for healthcare professionals would be essential.
4. Patient Demand and Experience: Patient interest and positive experiences can also play a role in the acceptance of alternative therapies. If individuals find value in sound healing and express a desire for such treatments, it may influence healthcare practices over time.
5. Regulatory Approval: Regulatory bodies play a crucial role in determining the legitimacy and safety of medical practices. For sound healing to become an accepted form of medicine, it would likely need regulatory approval and adherence to safety standards.

It's important to stay informed about the ongoing research in the field and to approach emerging therapies with a critical and evidence-based perspective. While sound healing and similar practices may hold promise, their widespread acceptance in mainstream medicine depends on meeting scientific and medical standards. It's recommended to consult with healthcare professionals before incorporating alternative therapies into healthcare routines, and to be aware that the landscape may have evolved since my last update in January 2022.