Hamada was taken to a nearby hospital with injuries to his face and legs, officials said on Friday.
His condition was described as stable. But his driver was killed and his bodyguard seriously injured, hospital officials said.
It was not immediately clear where the bomb was placed, but the explosion happened nearly 100m away from Hamada's home.
"We saw the minister's Mercedes car leaving the building where he lives," a resident, who gave his name only as Mahmud, said. "A few moments later we heard a large explosion and saw the car on fire."
Firefighters, rescue workers and police rushed to the scene as a large cloud of smoke rose into the sky.
Hamada was one of four ministers who resigned early last month to protest against parliament's decision to extend Syrian-backed President Emile Lahud's term by three years despite widespread opposition.
He is a close ally of Druze leader Walid Jumblatt, a long-time ally of Syria, but whose ties with Damascus have deteriorated since the extension of Lahud's term.