Drillbit.

in a near future where AIDS is the number one killer disease, an evil pharmaceutical boss, Dr. Hex, creates a drug called Serocaine, promoted as a miracle cure, that in reality results in hideous mutations. When Hex's top scientist discovers the truth he and his family are butchered by Hex's henchmen; their son Brian survives being drilled through the head though and becomes an unstoppable maniac bent on revenge....