My lingual nerve wasinjured during horizontally-impacted 3rd molar extraction.it's been 4 months now.i have pain & burning in tongue.any medications?

Maybe.: Some patients say that gapapentin (Neurontin) helps with nerve-related pain.

Lingual nerve damage: Nothing other than time will help heal your problem. Lingual nerve issues typically have a poor prognosis if sensation has not improve at a year. Your dentist should be following you up. They probably have you a corticosteroid either pull or injection already but it wouldn't hurt to ask. These things are unfortunate, but they happen especially with impacted wisdom teeth. Call you dentist and ask

Oral surgeon: If your 3rd molar was extracted by an oral surgeon, ask him about the next step. There are very specific protocols for handling nerve injuries. If you surgery was NOT done by an oral surgeon, see consultation with a board certified oral surgeon for help with management. There are meds which can decrease nerve pain.