Swells victim's eyes shut
The Conjunctivitis Curse (incantation unknown) is a curse that causes irritation in the target's eyes, causing them to swell shut like the infection conjunctivitis, commonly known as "pink eye". The Oculus Potion ends the effects of this curse.
Viktor Krum used this curse on the Chinese Fireball dragon during the First Task of the Triwizard Tournament. However, because the dragon could not see, she crushed some of her eggs that she was protecting, which lost Krum points. Sirius Black, while talking to Harry through the Gryffindor Common Room fireplace, was going to suggest that Harry Potter use this curse on his dragon as well, but was interrupted by Ron Weasley coming down the stairs because he heard voices.
- Harry Potter and the Goblet of Fire (First mentioned)
- Harry Potter and the Order of the Phoenix (Mentioned only)
- Harry Potter and the Half-Blood Prince (video game) (Mentioned only)