Remar, who used to work as a emergency medical technician, went into the store and bought a bandage and antiseptic cream, then returned to clean and dress the man's wound.
He also reportedly gave the man advice on how to treat the wound and prevent it from being infected.
Besides the starring role on Dexter, Remar has appeared on Sex and the City, the Mortal Kombat movies, 48 Hours, Miami Vice (television show), the Unit, Battlestar Galactica and X-Files, among others.
He is returning for the show's seventh season, which begins Sept. 30. It will be the pentultimate season of the series.
It's good to read stories like these. It humanizes people and shows us that sometimes people do good things just to do them. Remar didn't seek out attention for doing the humane thing - it was captured by a fan's camera phone.