| Yawning - excessive | ADAM Health Illustrated Encyclopedia |
| Yaws | ADAM Health Illustrated Encyclopedia |
| Yaws | Gale Encyclopedia of Medicine |
| Yeast Infection | Gale Encyclopedia of Alternative Medicine |
| Yellow fever | ADAM Health Illustrated Encyclopedia |
| Yellow Fever | Gale Encyclopedia of Public Health |
| Yellow Fever | Gale Encyclopedia of Medicine |
| Yersinosis | Gale Encyclopedia of Medicine |
| Yew poisoning | ADAM Health Illustrated Encyclopedia |