- Tom Kenny (SpongeBob SquarePants / Gary the Snail (voice))
- Bill Fagerbakke (Patrick Star (voice))
- Rodger Bumpass (Squidward (voice))
- Clancy Brown (Mr. Krabs (voice))
- Carolyn Lawrence (Sandy Cheeks (voice))
- Mary Jo Catlett (Mrs. Puff (voice))
- Mr. Lawrence (Plankton / Larry the Lobster (voice))
- Jill Talley (Karen Plankton (voice))
- Lori Alan (Pearl Krabs (voice))
SpongeBob SquarePants — S1E27
Episode: I Was a Teenage Gary
Air Date: 1999-10-28
Runtime: 11 min
Overview
Gary becomes sick when Squidward forgets to feed him, so a doctor has to come and give Gary some medicine. The doctor has Squidward give Gary the shot. Squidward accidentally gives the medicine to SpongeBob instead of Gary, which turns SpongeBob into a snail.