Serious adverse effects have not been reported in the available scientific literature. Theoretically, an intense session of music therapy inward focusing may cause pre-existing psychological problems or personality disorders to surface. Sound healing should not be relied upon as a sole therapy for potentially serious medical problems. Sound healing is usually used as a supplemental technique to other treatments, not as a replacement.

Sound healing may trigger physical symptoms such as rapid breathing or flashbacks that can be brought about by stress, anxiety or intense emotional experiences. If practicing sound healing produces anxiety, a qualified healthcare professional should be consulted. Though no adverse effects from sound healing have been reported, people with a history of trauma or abuse should speak with a healthcare professional before using this technique.

The material from which every sound producing object, tool or human voice arises is said to possess particular qualities. For instance, a gong may be created from one of several metals. Each of these metals, when struck, produces a different sound, which in turn creates a different type of healing environment. Further, each gong can produce several notes, and the notes also have particular healing qualities. Sounds are chosen on the basis of their specific healing powers. There is no commonly agreed upon classification of which sounds may heal a person. However, the sounds used in this form of therapy tend to be repeated for a long time and are not muffled.

The primary tool in sound healing is the instrument used to produce sound. Such instruments include gongs, metal bowls, crystal bowls, didgeridoos (a wind instrument created by Australian Aboriginals from wood eaten by termites), and Western-style instruments such as a violin. Sound healing might also be invoked by singing or chanting. In some cases, sound healing is said to occur by playing pre-recorded media created by artists or practitioners of sound music for this purpose.

There is no one way that a sound healing session may be conducted. Their form and duration vary. Many sound healing sessions are integrated with other complementary and alternative medicine modalities.

Sound healing may be practiced individually or in groups. In a group setting, a patient may sit passively and simply listen to the sounds in a session, or he may contribute to the process of creating the therapeutic environment for everyone involved. A group may gather together to help each other heal, or they may gather with the intent of healing a single person in the group. Some patients choose to orchestrate their own sound healing sessions by producing music or noise with the intent to heal on their own.

Sound healing functions on the philosophy that all atoms exist at a particular threshold of vibration. The atoms in a person or environment therefore take on a certain level of vibration. When the body is sick, the level at which a person vibrates might be abnormal. Illness occurs when these atoms comprising the human body vibrate at unhealthy frequencies. Illness results from the unhealthy frequency, because body functions cannot take place as they should.

Alternatively, a healthy body may succumb to illness when it is surrounded by unhealthy environmental frequencies, including noises or fields of energy. An unhealthy environment that is "out of tune" with a state of good health may cause the people in that environment to also be "out of tune." As a result, the patient's body may begin to resonate at an unhealthy frequency and, illness results.

Sound is generally believed to target various aspects of the body's ability to heal, and the frequencies played in therapy aim to correct the imbalances. Emotional problems or a reoccurring infection are two examples of imbalances that proponents might use to help a patient become more well.

There have been numerous studies to gauge the effect of playing music on perception of pain, and anxiety of patients experiencing moderate to severe discomfort, such as after open-heart surgery.

A 2007 study by Wachi et al. found that male Japanese corporate employees under high levels of stress had healthier immune systems and were more relaxed if they participated in recreational drumming than the control group. The study participants engaged in group recreational drumming or read leisure materials as a means of relaxation for six months.

A 2007 study by Mitterschiffthaler et al. found that healthy patients who listened to happy or sad classical music while getting a functional MRI demonstrated arousal in the some areas of the brain that process emotion.

In a 1998 study by Good et al., researchers found that Taiwanese patients were agitated by listening to jazz music that was played in an experiment with the intent of reducing postoperative pain. At the completion of the study, these patients reported that they would have preferred Buddhist chants or Taiwanese pop music. The results of this study imply that the emotional state associated with a genre of music is at least, in part, culturally determined.

While the results of these studies are varied, none have measured sound as a means of inducing the process of healing unto itself. In other words, soothing sounds have been investigated to boost immunity or encourage relaxation, but not to heal an infection or entirely resolve mental illness.