I use lidocaine patches and they have absolutely helped my minimize my spread. Taking a bath with Epson salts for a soft tissue injury is a good idea as well, along with taking extra Vitamin C. If you have pain meds, and your prescriptions allow for flexibility in the dosages taken, than it's a good idea to increase your amounts for a few days.

If an accident has caused a major flare and the above don't help, then a stellate ganglion block or ketamine infusion should be considered.