Based on the paragraph below, what are some potential benefits of TENS (transcutaneous electrical nerve stimulation) treatment?

Context: Transcutaneous electrical nerve stimulation is a commonly used treatment approach to alleviate acute and chronic pain by reducing the sensitization of dorsal horn neurons, elevating levels of gamma-aminobutyric acid and glycine, and inhibiting glial activation. However, many systematic reviews and meta analyses assessing clinical trials looking at the effectiveness of using TENS to reduce different sources of pain have been inconclusive due to a lack of high quality and unbiased evidence. Potential benefits of TENS treatment include the safety, relative low cost, the ability to self-administer, and availability over the counter without a prescription. In principle, an adequate intensity of stimulation is necessary to achieve pain relief with TENS. An analysis of treatment fidelity showed that higher fidelity trials tended to have a positive outcome.

Answer: Some benefits of TENS treatment are the low cost, ability to self-administer (which lends itself to flexibility, and being able to treat at home), and availability without a prescription.