TENS is safe firstly. People vary in how much they like it but some people do find it supportive in a pain management program. It is easy to use and can be taught for home use.

Dear Jane

Thanks a lot for your help

PROS

It is a drug-free option for pain management

Non-invasive method of pain relief

Endorphins release by the body

Help to relief DIFFERENT type of pains 

Easy to use, allow you to use it in your own home or wherever you want

Pretty safe

In some cases, pain medication can be reduced, or eliminated

CONS

It can be hard to find the best device in the market, it is a professional advice. 

It could take several sessions before a good result.

Exists controversy of its effectiveness, more quality research must be done.

Works best on localized pain than large areas