In the original, Dr. Mario was briefly mentioned in Mario's biography, among his many other past professions.
In Super Smash Bros. Melee
As a Playable Character
Dr. Mario appears in Super Smash Bros. Melee as one of the thirteen new characters introduced. He is a secret character and considered to be a "clone" of Mario, since he is a slower, yet stronger version of Mario. While not many significant differences exist between the two characters, there are a few - the main one being that rather than shooting Fireballs as his Neutral B move, he throws Megavitamins. The subtle differences between Dr. Mario and Mario work to Dr. Mario's favor in the competitive scene, and place him slightly higher on the current tier list.
Dr. Mario, like the rest of the playable characters, has three different trophies dedicated to him. The Viruses from the Dr. Mario game also appear as a trophy. His Classic mode trophy is as follows:
Immaculate in his medical garb, Dr. Mario destroys killer viruses with his amazing vitamin capsules. With his dedicated nurse, Princess Peach, at his side, Dr. Mario spends day and night in his laboratory working on new miracle cures. Somehow he's managed to keep up with all the new viruses that have arisen over the years.
- Dr. Mario, 10/90
Dr. Mario receives representation in Brawl with two songs:
He is also a sticker compatible to Mario, Luigi, Peach, Bowser and Yoshi.
Hacking has revealed partial programmed data in Brawl for Dr. Mario. Some take this as signs of a planned character, but it is also likely, if not more so, that it was there for referential purposes by the programmers, or data imported from Super Smash Bros. Melee. He also may have been an alternate costume for Mario.
Dr. Mario returns in Super Smash Bros. for Nintendo 3DS and Wii U.
- Dr. Mario is the first character to make a reappearance after being excluded from a previous game.