What are the normal side effects of radiofrequency ablation?

Pain. I assume you are speaking of spinal medial branch facet joint ablation. Most patients understandably want immediate relief. Some do get that. Others do not. Some times it takes a couple of weeks before you notice a difference. It does not work on some people. But the "normal" side effect is continued discomfort up to a couple of weeks. If pain exceeds that it probably is not going to work.
Usually none. Radiofrequency(rf) ablation usually creates a tiny scar in the heart, only a few millimeters in diameter. It has no effect on the overall heart function. The incision sites for the catheters are usually about 1/4 of an inch and heal within a few days. Rarely (<1%) normal parts of the heart's electrical system can be damaged during an rf ablation such that a permanent pacemaker may be necessary.
Generally Good. Radiofrequency procedures work well if a previous facet injection or medial branch block was performed with greater than 75-80% relief that was obtained. As with anything there are failures, but quite low if the block worked well. Risks are the same as with any spine procedure, no different. Rare that you would be worse off afterwards.
Side effects. Typically there are none. Some people have chest or groin discomfort for a short time (days or weeks) after the procedure. I have also had quite a few patients complain of palpitations (not typically sustained fast heart rates) afterward. This usually gets much better very quickly.

Related Questions

What possible side effects could radiofrequency ablation have when done on lower back nerves without anesthesia?

Radiofrequency Ablat. More side effects from anethesia. The main side effect of radiofrequency ablation is some discomfort, including swelling & bruising at the treatment site that usually goes away after a few days. Leg numbness may develop due to the local anesthesia given during the procedure. It should only last a few hours. Mild back discomfort can occur as the local anesthetic wears off & typically lasts 2-3 days. Read more...