Oops, it doesn't look like 'cough syrup day' is a national day..

Other days

unicorn

Unicorn Day
youth

Youth Day
tulip

Tulip Day
comfy

Comfy Day
ruby

Ruby Day
kiss a ginger

Kiss A Ginger Day
ormille

Ormille Day
self care

Self Care Day
lash

Lash Day
carpenters

Carpenters Day