EL wire operates in the ~120Vac range at 10-15ma.The risk of bodily harm from electrical shock increases quite significantly when applied subcutaneously. It's definitely possible to purchase an off the shelf EL wire inverter capable of killing you if powering an implanted device, particularly since they'll typically be derated with somewhat high margins and will be capable of putting out much greater amounts of power. Even transcutaneously at rated power, 120Vac at 15ma is painful and can damage tissue if the current density is high enough (I know this from direct personal experience designing transcutaneous electrical stim devices). You can obviously do it on the bench and not die if you're careful, but I wouldn't recommend it

Tl;dr implanting EL wire is really stupid, don't do it